Shotgun proof pressures. The watertable has some obsolete proof marks.

Shotgun proof pressures. Proof pressure according to CIP.

• Shotgun proof pressures 13,500 PSI The proof-house charge of the American Testing Institution for a 12-bore gun develops a gas pressure of over 18,000 lbs. The X within a shield with a knight's helm above is the mark of the Eibar Proof House. Thus, a 2 1/2" chambered gun, 1925 rules With shotshell chambers varying in length and diameter, exact pressure cannot be predicted. See less See more Shotgun pressures are LOW. 2. Frank . Proof Marks. The difference in pressure of I would need a shotgun 12/76 for hunting, like old tools. Legally they are not allowed to manufacture and sell a cartridge which exceeds 700bar pressure and a 2 1/2" chambered gun is proofed for 850bar (3 tons). It's also equally possible SAAMI compliant ammunition would not produce over-pressure in your gun. Before one start with the technical details, one must understand somewhat of the history of the way in which shotguns have been proofed in modern times. A good gun really should be proved at 20,000 p. proof loads ( a big "if"), then the gun will be proofed by a lot of no less than Modern Shot gun barrels are actually proof tested to 18,000 to 20,000 psi before they are sold. They worry that if they shoot excessive pressure loads that their shotgun could well “blow up. /cm sq. Proof Load The 19,000 PSI or 1320 bar proof is certainly more than needed for common 12,000 PSI (or less) shotshells. Jump to Latest I can not provide solid numbers which is great because unless the gun in question is as new when looking at old used gun this info is pretty much of little of no value. Metalic cartridges operate at very high pressures. shot with published pressures “about 5 Tons” = 11,200 psi + 10-14% You are aware that the barrels were not Sporting Arms & Ammunition Manufacturer Institute (SAAMI) Shotgun Pressure Specifications Shotshell Maximum Average Pressure (MAP) in PSI 10 gauge / 11,000 psi 12 gauge 2 ¾" & 3" / 11,500 psi 12 gauge 3 ½" / 14,000 psi 16 gauge / 11,500 psi 20 gauge / 12,000 psi • The Maximum Average Proof Pressure is calculated by multiplying the Maximum There isn't a direct link between psi. Please note that this is way under the 20,000 PSI number. lead shot. Jump to Latest 61 - 80 of 84 Posts. Russian Proof A big thanks to Per for collecting this. Thus, a 2 1/2" chambered gun, 1925 rules of proof, would be equivalent to 3 tons; a 2 3/4" chambered gun to 3 1/4 tons. Between 1925-54, the chamber length was marked. still thinking about her. The crossed long arms with a superimposed numeral "2" was used as a provisional black powder proof with minimum proof pressure of 8,818 psi, however, later records also list this mark as a smokeless powder proof The proof pressure test is a once only test applied at the time of proof. U. has not been proofed for ammo. In 1884 he registered four patents, No. Table 1 Average pressure measured at 25mm and 115mm from the Can we see a picture showing the proof marks on the action and under the forend (may need to unscrew woodwork) on the barrels? On a side note nearly all 2. This is an older thread, you may Under the BRITISH 1896 Rules of Proof Pressures 12g 2 1/2” and 2 5/8” chambers (bore . If you want more velocity, go to a slower burning powder and use more of it. The 11-87 is safe for all of these loads when so chambered, and rated for steel since it's inception. So, I started by firing loads which developed 20,000 psi in the test Remington 870 barrels. It is like converting LUPs to PSI!! The Proof Master The Gun Barrel Proof House Banbury Street Birmingham B5 5RH United Kingdom. the Fourth looks like two swords behind a shield with the letters CH in it. The number of licensed shotguns and air rifles declined from 652,000 in 1981 to 493,373 in 1989. guns. It was designed by Georg Luger in 1901. New guns are proof tested. As I described above: Re-enforced smokeless proof for shotgun barrels with a proof pressure of 12,801 psi. RandyWakeman. Most modern shotgun barrels are designed to take up to 35-50,000 PSI before they experience catastrophic failure. , or twice the average maxium service pressure. That doesn't mean that it is ok to regularly shoot loads in excess of 11,500 PSI. Wee,wee. those proved to 1370 bar (transducer) or, previously, 1200 bar (crusher)) must not exceed the maximum admissible service pressure of 74 MPa (new units megapascals, in place of the old 740 bar) STEEL SHOT AMMUNITION AND SHOTGUN PROOF This paper summarises the current CIP (Permanent International Commission for the Proof of Small Arms) regulations relating to steel shot cartridges for 12 and 20 bore must not exceed the maximum admissible service pressure of 74 MPa (new units “megapascals”, in place of the old 740 bar) specified by the CIP and The reason it doesn't explain the relationship between velocity and the proof pressure is that velocity is not involved. 12,500 PSI. About 10,000 lbs. There is nothing you can measure. Am I missing something here? Max. MAP x 1. Why are Shotgun Proof Marks Important? Shotgun proof marks hold great importance for both gun manufacturers and firearm owners. to the square inch. Proof loads are usually 15,000 p. , it is very likely that it was designed for 50s 3 1/2" 10g loads. why was a 2 tier introduced? well most likely it was introduced because of 930bar mean Proof pressure. It seems that most European proof houses are concerned with the working pressure of the gun, not the so much the max pressure. S. When I discussed pressures with Tom Armbrust he recomended staying at about 65% of proof Magnum proof- the shotgun fires two proof loads from each barrel producing 1370 bars, about equal to kilograms per square centimeter and atmospheres. 5" 10 ga. Modern U. e. CIP Shotshell Pressures - Free download as PDF File (. Each publishes proof testing The proof load for my gun is 1630 barr (23,641 psi) (Fabarms) No one else proofs this high. Spanish guns are modeled after the British game gun as is built with the same purpose in mind. Hopefully Randy will let us know what the 1550 BAR = 22,481 psi is referencing; Modern Shot gun barrels are actually proof tested to 18,000 to 20,000 psi before they are sold. 11. To this day (4) Notice that all the shell pressures are below proof load pressures. with 1 1/4 oz. Mark. So, if the gun is proofed for 960 bar, you should be able to feed it a steady diet of those loads without danger of destroying the BARRELS! On the other hand, the whole gun is designed for a very different purpose. 12 Gauge shotguns with 2 3/4 or 3 inch chambers are proof tested @ about 18,000 PSI. See less See more 3 --Randy Guns & Shooting Online. Proof loads will produce pressures well in excess of whatever an extra 4 grains of powder will exhibit. 12. shot. The initial London date stamp from 1972 also included Mid 50's Belgian Proof Pressures (PV) Tags 11ga 1950s belgian 10ga pv pressure double magnum. ) 12 gauge 3 1/2 in. ANSI/SAAMI Barrel Attachment Requiring Proof means a device forming any part of a barrel, removable or otherwise, from or through which any part of the Load would be discharged. Thus, a 2 1/2" chambered gun, 1925 Yes sir, it's possible. under SAAMI guidelines has a service pressure of 14,000 & is proofed at 20,500 psi. 17 PSI. See page 1. Japan does not have a gun barrel proof act, but the "LUP" was used by most powder manufacturers for testing of shotgun load recipes until well into the 1980s or 1990s. SAAMI uses 2/3 of the proof pressure as the service pressure. Reactions: Arto Kuusistosta. This is all explained in the publication Wobbly1 noted. The 3 Tons refer to the SERVICE pressure that the gun has been proofed for and contemporary cartridge boxes were marked with this information so that the compatibility of the cartridges and gun could be assured. 5037738 psi, so instead of 96,000 psi, the result was 98,625 psi. A forum community dedicated to Shotgun owners and enthusiasts including the Remington, Beretta, and Mossberg shotguns brands. Once someone gets off their butt and actually patterns several 'low' pressure loads compared to several 'high' pressure loads, they will see just how wrong they Low Pressure Loads Jump to Latest Follow 806 views 3 replies 2 participants last post by JimfromTrafalgar Oct 9, 2003 From Tom Roster: "Where excessive shotshell pressures generally occur is in improperly put together reloads. gun websites. The 1370 bar proof is obligatory for all guns 3 1/2 tons = 10,427 PSI, Which campares to SAAMI's 1992 (current) standard of 11,500 PSI for 12 gauge 2 3/4" or 3" chambered guns. That 9mm firing rapidly a few inches from your face has a MAP of 35,000 PSI. made shotguns, regardless of action type are proofed at the same levels. You do not want your recipe to result in pressures higher than these. A used firearm may, however, be accepted, The CIP High Performance 3" and 3 1/2" (Magnum & Steel) is for a Service Pressure of 1050 BAR = 15,229 PSI, and Mean Proof Pressure of 1320 BAR = 19,145 PSI. 710-. I've seen other moderated guns on the U. If your . A shotshell hull cannot withstand that kind of pressure without support from the chamber, but pressure does, like the fellow said, peak before the wad clears the hull. At one time I had a document that showed what the actual pressures were. 5" 12 ga. Standard 12 bore steel shot cartridges. To help you visualise the proof pressures in a 12 gauge shotgun, the standard proof pressure of 930 bar is roughly the equivalent weight of an early 1970’s Porchse 911 on 1cm of your barrel. 410 Bore 2 1/2 in. Chamber pressures and proof stamps This in my simple minded reasoning means that the gun was proof tested to 7000 psi in English tons. If not, the gun must pass a suitable proof and this stamp is put on the barrels We know there are published specifications on shotgun proof testing pressures. i. 7% less than the value Q given in the CIP Tables, remains with the limits given in the Tables. When is a gun out of proof? A gun is considered ‘out of proof’ when the barrel is materially altered or damaged (for example, there is a hole in it or the chambers have been extended). 5" traditional hunting 410 2. Proof pressure is 19870. But that doesn't mean they are safe for "extended use" of these proof loads. European (CIP) proof pressure of 850 kg per sq. 7 Tons would be in the 20,000 PSI range which compares to SAAMI's current proof pressures of 19,000 to 20,500 PSI. High pressure takes on an element of perceived danger, because many shotgunners have been taught that so-called high pressures can cause shotgun barrels to “blow up,” bulge or split. 2 and 2 1/2 inch chambered guns are proofed differently, and you'll need to check the original proof of the gun. But I would need a shotgun with gun barrel that can use steel shots, not led shots. 900 BAR is for The SAAMI standard proof pressure is about 19,000 psi, similar to CIP Superior Proof. and the figures stamped by the Proof House, you can't say that 2240 (pounds in an imperial ton) x 3. Proof testing is nominally a Shotgun Barrel Failures Caused by Accidentally Mixing 12 bore and 20 bore Cartridges This report is a precis of work undertaken at Cranfield University, Royal Military College for the 12 bore test cartridge and the 12 bore cartridge loaded to proof pressures (average of five cartridges fired for each position). Once you have the proof pressure, you can convert it to psi and multiply by . DamascusKnowledge www. Most modern guns are actually proof tested at 18-20,000 PSI before they are sold. My friends at Accurate Powders / Western Powders inform me they have seen LTC Calvin Goddard reported in "Army Ordnance", 1934 that Parker followed the SAAMI standards of that period: 13,700 psi proof, 9500 psi service for 2 5/8" chamber; 15,900 The proof-house charge of the American Testing Institution for a 12-bore gun develops a gas pressure of over 18,000 lbs. SAAMI proof pressure for standard 2 3/4" 12 ga. 5. 1929-> Eibar. CIP Max. A proof load generates pressures far in excess of the accepted service pressure. The SAAMI only lists transducer pressures for Shotshell cartridges. Additionally, any possibility that a gun owner will shove a baby magnum exceeding 740 bar causes makers to veer towards caution and submit even 70mm chambered If you lengthen the chambers you render the gun out of proof, which means that this outfit, whose only business is understanding gun barrels, says that lengthening the chambers can weaken the barrel while lengthening the forcing cones does not. I hazard a guess your gun will be 70mm (2 3/4" equiv) and thus Proofed to 850 Bar. They really aren't gouging, just that there isn't that big of a demand for them, so they don't produce Proof loads are to assure that they are safe with normal loads. To this day the voting member companies design, meet, agree and then vote on any new ammunition or testing procedures and not have it shoved down their throats by another government agency. Current practice has proof pressures at 1020 and 1370 bars for normal and magnum proof. 25 mm and max. Most modern shotgun barrels are actually proof tested at or about 20,000 PSI. se. fps 1,300). At or above the 12 bore magnum pressures), so cannot see any reason not to use 3 inch if the chambers are long enough. If you find any errors or missing information please, please, please let me know by sending me a e-mail to: Tobias(a)shotguns. We had the Remington class-action suit (the Garza suit), etc. 5" regal game 28 bore 2. Tha Baikal shotgun is most interesting. Proof is the process of testing the safety of a gun barrel. The only shotguns that get proofed for 14,000 PSI are chambered for the 3 1/2" 12 Gauge. The majority of their cartridges are in the range of 500-600bar typically - Lyalvale have a SAAMI pressures for 2 3/4 and 3 inch chambered guns are rated at 11,500 psi. average pressure established by SAAMI for ammo. those proved to 1370 bar (transducer) or, previously, 1200 bar (crusher)) must not exceed the maximum admissible service pressure of 74 MPa (new units megapascals, in place of the old 740 bar) This issue was also discussed by John Brindle, author of Shotgun Shooting: Techniques & Technology, in a review of Proof and Service pressures in Part 5 of his series in The Double Gun Journal, "Black Powder & Smokeless, Damascus & Steel"; Volume 5, Issue 3, 1994, "Some Modern Fallacies Part 5", p. The Maximum Statistical Individual Pressure of 850 BAR = 12,328 psi under CIP rules; for shells with a Maximum Average (SERVICE) Pressure of 740 BAR = 10,733 psi. By the same token, it's possible C. D. those proved to 960 bar (transducer) or, previously, 850 bar (crusher)), or magnum proof shotguns (i. The SAAMI proof pressure for this popular gas gun on the In 1914 the Liège Proof Master (1908 - 1946) M. 12g 65mm and 70mm "standard proof" lead or steel (limited to no larger than 3. #2. B. but that may be because there are no short chambered 12ga guns being made in the US right now. with pressures like that, pressure signs become discernable. proof pressure for steel shells is 1370 transducer BAR = 19,870 psi Max. 5 grains for a 1200 fps shell producing 9940 PSI. Go. To put things into perspective, we are talking about a 2500 psi maximum pressure increase. / 1,310bar. 801 psi. Our three major activities are: gun proof, safety and de-activation. 090 psi. It also tells you how much pressure your gun is built to handle. One star over the PSF (Polvere Sensa Fumo- Smokeless Powder) indicates "normal", ie non magnum nitro proof. Pressures that actually damage an unobstructed bore in a modern shotgun, will be well past proof pressures. On a national level a lot of countries have used different proof methods, but at the bottom line - the simple fact is that there have been no DLM is right on. I don't have any American made shot guns to see if they have proof marks. Silver_Is_Money · Registered. ” They’ve heard that from For 12 bore shotguns there are two levels of proof, Standard at 850 Bar minimum for chamber lengths up to 70mm and Superior or Magnum at 1200 Bar minimum for all chamber lengths above 70mm. Barrel length These numbers SHOULD apply to guns proved under the 1925 rules, which were stamped only with chamber length and shot charge. 740) were proved for a maximum service load of 3 1/4 Dram Eq. Proofhouse. It was originally designed to handle 26g to 28g load at 65MPa or less. proof pressures and testing procedures. 410 is in proof for 3" cartridges it should be good with either 2 1/2" or 3". , which is about one and a half times the average maxium service pressure. I assume the Turkish ammo makers are perfectly capable of producing loads to proof pressures. However, keep in mind that mildly excessive reload pressures are continuously stressing the gun and contribute to high recoil When we say shotgun shells don't show pressure signs we are really saying that if you see permanent deformation you're way over safe pressure. (higher pressure proof). The formal test pressure for ALL guns at CIP proof houses is either 960 or 1370 bars. sold in the USA. The 3. Now this would seem to be inadequate for many 20 ga factory hunting loads and many hand loads that would exceed 7000 psi chamber pressure. 45-70 max. Save Share Reply Quote Like. It is still done as it has been since the Company was established in 1637: by firing the gun with an over-pressure So on a British gun the stamp 3 1/4 tons, or in a Russian gun the 750mpa are the service pressures, not the proof pressures. 45-70 was a common shotgun conversion; this is a Smith As you can see the liner is quite thick The . [XXIX-41] 7. The good news is that if we use 75% of the proof pressure of a gun proofed with the crusher system, you will have a small increase in the safety factor as The proof houses will NOT accept guns for steel proofing if they were not specifically designed to withstand high performance steel proof pressures. Most modern shotgun barrels require around 50,000 psi before they fail. I think if I put one on my skeet gun it would turn a few heads and be quite a novelty! There doesn't seem to be much interest in the US for moderated shotguns. What about the chamber test pressures of the major firearm manufacturers? aerod1 -- If you are asking about the "Proof" load pressure, they are about 55-70% greater than the mean service pressure. together with such details as bore and chamber dimensions of shotguns. Turkish Shotgun Proof Pressures | Shotgun Forum Proof Pressures. #1. (BAR) = 13,920 psi proof pressure= 10,730 psi service pressure (SAAMI) Per the 1954 Rules of Proof, here are the equivalent service pressure values: 3 tons--8,938 psi guns proved under the 1925 rules, which were stamped only with chamber length and shot charge. 5 inch nitro 410 cartridges operate at similar pressures to the 3 inch (i. A bar is equal to 14. London. , that C G Bonehill was a Guardian of The Birmingham Proof House. pdf), Text File (. British guns bearing Birmingham proofing have markings including, for example, 3 1/4T, 2 3/4" and 1 , 1 1/8 or even 1 1/4 oz. P. These cartridges, if they are to be fired from standard proof shotguns (i. The higher of the two pressures is nearly the maximum SAAMI-approved pressure. The proof tests are about half of destruction pressure and one and a half to two times maximum factory ammo pressures. On all others the pressue indicated on the gun is the proof pressure and must be reduced by 25 per cent to figure the service pressure. Sort by Oldest first Oldest first Newest first Most reactions. The barrel never actually burst. The number you found in the manual might be the proof pressure for that gun. 14402. 410 Bore 3 in. fps 1,300) SERVICE pressure 740 BAR = 10,733 psi; Maximum statistical individual pressure 850 BAR = 12,328 psi; PROOF 930 BAR = 13,489 psi. High Performance Steel ammunition can only be used with shotguns bearing a CIP fleur de Lys mark, as represented in the above Shooting a round overcharged with powder produces higher than normal pressure inside the barrels and action when the gun is fired. 14,000 PSI 16 gauge 11,500 PSI 20 Gauge 12,000 PSI 28 gauge 12,500 PSI. The increase in powder from 11,000 PSI to proof levels will very likely be more Using the convention that the maximum service pressure should not exceed 2/3 the service pressure, this gun should not see pressures in excess of 0. Further information about the marks and other Proof matters can be found in the booklet “Notes on the proof of shotguns and Maximum Statistical Individual Pressure 850 BAR = 12,328 psi Mean PROOF Pressure 960 BAR = 13,924 psi 12g 3” & 3 1/2” “High performance/Superior Proof” lead or steel Maximum Average (Service) Pressure 1050 BAR = 15,229 psi Maximum statistical individual pressure 1200 BAR = 17,405 psi Magnum proof 1320 BAR = 19,145 psi High pressure takes on an element of perceived danger, because many shotgunners have been taught that so-called high pressures can cause shotgun barrels to "blow up," bulge or split. Historically, the SAAMI pressures have not changed in about 100 years. SAAMI provides for a mean average of 19,800 psi proof loads for proofing such barrels. Over time powder has evolved and measurement methods and units has changed. The conclusion is tha, guns produced with 3 inch chambers MUST pass proof at 1370 bar. Reactions: desmobob and Shotgun pressures are LOW. The quality of steel sure has. These cartridges, if they are to be fired from standard proof shotguns (ie those proved to 960 bar (transducer) or, previously, 850 bar (crusher)), or magnum proof shotguns (ie those proved to 1370 bar (transducer) or, previously, 1200 bar (crusher)) must not exceed the maximum admissible service pressure f 74 MPa (new In the US we do not require gun proof, but the shell pressures are limited by SAAMI to 11,500 PSI for 2-3/4" and 3" 12 gauge loads, and 14,000 PSI for 3-1/2" 12 gauge loads. If you do see such a shell, do NOT attempt to fire it through your personal gun. The fifth looks like a diamond, with the letters "NAD" inside. per sq. Optional smokeless powder proof with a proof pressure of 12,090 psi. There is a difference between proof testing a gun and destruction testing it. SAAMI and CIP also establish CIP Max. /1,413 bar. The current Rules of Proof, those of 2006 , were approved by the Secretary of State to come into force on The V stamp denotes a Superior or Re-enforced Proof where the longarm is exposed to a higher than normal proof pressure. Jump to Latest 689 views 3 replies That is probably BP, not GP. For example, in Europe, C. CUP values are no longer part of the SAAMI Manuel. Re-inforced smokeless proof for shotguns barrels with proof pressure of 12. Denali Bob Discussion starter 144 posts Here’s my question: Do I need to be concerned with either shotgun since they both shot high pressure rounds? I disassembled both shotguns and saw no issues with barrels and bolts. These marks were used by the British Proof Houses from 1954 to 1984 when they went over to the PROOF pressure in Kgs and then 1989 they went Rule 10 states that if a Nitro Proof is specified by the gun sender (Edit: w/o specifying a particular powder) a second Supplemental Proofing will be performed with Curtis and Harvey's TS 2, a fine grained fast burning Blackpowder that, on a weight/weight basis, produces pressures substantially above that of the standard grain size proof Blackpowder. This is an older thread, you may PROOF/PRESSURE British proof markings: The "tons" mark (which is service pressure) was not used until 1954. 31. In 1880 he patented a shotgun action and stocks (No. proof tested to "HP pressures". 5 = 7280 psi. He needs to do this in order to examine the Modern commercial shotgun ammunition is maxed out at about 12,000 PSi. The One of these standards is maximum average pressure for 12 gauge 2 3/4 inch shotshells and the number is 11,500. The service pressure is the pressure the gun withstands throughout its life. 10 gauge 11,000 PSI 12 gauge 11,500 PSI (except 3-1/2 in. These proof pressures mean you use cartridge producing 25 per cent less pressure, so a 1370 proofed gun should not exceed 1050 bars Spanish guns are modeled after the British game gun as is built with the same purpose in mind. is 19,000 to 20,500 psi. 1670-1955 Proof pressure according to CIP. ["CriscoKid", alias: Fat in the Can] There was no proof pressure in 1926. I would have no fear of shooting it at all. " Gauge/bore Chamber length (in. Numbers are transducer BAR converted to PSI. The Super-X 3 1/2” 10 Gauge Magnum had 2 oz. A proof test is a form of stress test to demonstrate the fitness of a load-bearing or impact-experiencing structure. By the time you see signs of over pressure the loads will well over proof pressures. Just simple economics: higher cost to producer = higher costs to consumer. Tom Armbrust tried to burst a Winchester Super X-1 barrel years ago and the pressures were well into the 50,000 PSI range(yes I have my figures correct), when the barrel finely bulged and cracked. I am not sure that is how Eibar intended it to be & they would probably pass a higher proof standard, but I try to use loads in that pressure range just to safe. Some exceed 60,000 PSI. It is also interesting 4 tons--11,917 psi These numbers SHOULD apply to guns proved under the 1925 rules, which were stamped only with chamber length and shot charge. Here is a list of SAAMI Maximum Average Pressures for the various gauges. Guns proofed for "high performance steel" under CIP standards have a higher proof pressure than SAAMI proof. 1,05. Good luck. Above the table there (4) Notice that all the shell pressures are below proof load pressures. 1 4 of 5 Go to page. But these are generally mild excess pressure situations, not gigantic ones involving double and triple charges of powder. I reload for sporting clays, using a MEC progressive, 12 ga. No gun would stand such a strain for any length of time. The maximum average cartridge Today, all International Proof Commission (CIP) Proof House use the Radial Transducer system to measure pressure, with bar as the unit of measurement. 13667. Very, very low. I'll take their word for it. so theoretically if a gun has 70mm chambers it most likley NOT High performance proof tested. The difference is important! Chamber mods "take the gun out of proof. The way a primer looks means nothing. Serbus, Raimey rse . 16. may be considered of touching the safety limit, and for some guns even is Additionally, for guns bearing European Proof Marks, the information given is the proof pressure in kg. Max Pressure Considerations. Proof pressures. ) the pressures developed by both service and proof cartridges: in hunting, target shooting, and self defence weapons, with the exception of weapons intended for land, sea, or air warfare; however the Proof loads, other than being in a clear hull with 'Proof' written on the side, do not show any signs of high pressure. for 3" shells is 11,500 psi Yildiz guns imported into a CIP member country are proved by that country's proof house. In fact, my 2000 Alliant and 2005 Hodgdon reloading handbooks still showed rifle load pressures in "CUP" (the C is for the copper slugs used, rather than lead for the higher pressures). , you need all the help you can get. PSI was not measured at all, for it was not pounds per square inch, nor was it direct pressure readings: it was the imprecise lead crusher units of If lesser gun makers can make steel approved barrels, as you said, why can't they when they charge 3-4 times as much for a gun? over the hill and picking up speed. generating 11,500 psi, which is the max. txt) or read online for free. I. pressure is 15,228 PSI for 3 inch 12 and 20 gauges. L2. Above the table there If you have a standard-proof gun with NO Fleur-di-lis proof stamp: CIP maintains that it will not be damaged by shells firing steel shot with a velocity of no more than 1,300 fps, AND a shot size no larger than U. You need to go by published data or have the loads tested. Ref. An individual proof test may apply only to the unit tested, or to its design in general for mass-produced items. Personally I don't shoot any load exceeding 7500 psi in my Lang. The old systems are not simply This document provides specifications for calibers of smoothbore center fire shotguns, including nominal case lengths and diameters, chamber lengths, and maximum pressure values. Pressure (psi) Load Oz. One of the commonest problems in old guns (particularly big bores) is the degree of pitting not allowing the viewer to "throw a shadow" down the barrel. 8471 covered a shotgun, and They're the pressures considered safe in the chambers of modern shotguns. (Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives) is the primary proof testing organization; in the US, it's Sporting Arms and Ammunition Manufacturers' Institute (SAAMI). Sticking to 2 1/2" shells of proper pressure is a fine alternative. SERVICE pressure 740 BAR = 10,733 psi; Maximum statistical individual pressure 850 BAR = 12,328 psi PROOF 960 BAR = 13,924 psi 12g 76 mm = 3" LEAD "High performance/Superior Proof" If you’re unsure whether your shotgun is suitable for use with Standard Steel ammunition please contact a competent gun dealer, gunsmith or the British Proof Authority for advice, this may involve the submission of your shotgun for inspection. Good luck laddie. It lists over 30 specific shotgun calibers along with BOTTOM LINE: ANY 850 BAR (proof) = 650 BAR service or 3 TON service gun should be fine at pressures under 8500 psi, or 3 1/4 tons less than 9,500 psi. (1220 fps) The Proof House did not publish pressures but other period published pressures with Bulk Smokeless powder were 7,000 - 8,500 psi Major Sir Gerald Burrard, The Modern The maxium SAAMI pressure limit is 11,500 for all but 3 inch shells in 12 gauge. However, the CIP hi-performance shells are getting close to the CIP standard proof pressures. Date marks. The SAAMI max. Both 65 and 70 mm 16g standard is SERVICE 780 BAR or 11,313 psi; PROOF 980 BAR or 14,214 psi. Shotgun World General Forums. A simple primer change can change pressures by 3000 PSI. because the testing method does not directly measure the Proof pressure, it infers it from the degree to which a lead slug is deformed in a special barrel. In any The gun in question was proofed Nitro in Suhl in 1936 with 70mm chambers. We also found a lion over a “PV” indicating a nitro proof. Proof marks on Japanese shotguns. 000" from the breech face. Lefteris. The "blue pill" loads to proof test US barrels/actions are also overloads of a similar nature. Jump to Latest There should also be a set of numbers that tell the proof pressure of the particular gun. So much for low pressure loads for older shotguns!!!! SAAMI proof pressure for 2 3/4" 12 ga. I'd guess that continual use of the hi-performance loads at 1050 bar will cause a gun proofed at 1120 bar to shoot loose sooner rather than later. 5" traditional hunting 410 3" If an English gun is in proof Gamebore 2 1/2" cartridges should be appropriate. 20. A 12 Gauge shotgun with 2 3/4 or 3 inch chamber(s) are designed for a maximum average service chamber pressure (or breech pressure) of 11,500 PSI. Trying to sort out & converting the proof numbers is enough to make you go bald prematurely. Assuming there are no measurable signs of wear in the barrels and the shotgun locks up tight and it is seen by a qualified gunsmith, it should be safe with standard loads. SAAMI has made their There is no question, pressure has little to do with pattern performance, regardless of pellet type. The The Z gun withstood a 6800 bar test. 32 . Guns imported must have valid proof marks accepted by Eibar proof house. fps Some proof marks also indicate that the gun has been subjected to a specific level of pressure testing, ensuring it can handle the expected pressures generated by firing ammunition. The document also notes that pressure values listed for high performance cartridges and proof A proof test is a form of stress test to demonstrate the fitness of a load-bearing or impact-experiencing structure. I have been using Alliant Clay Dot 17. Average Proof Pressures is less than 1,500 psi, the Maximum Average Proof Pressure shall be positioned 1,500 psi above the Minimum Average Proof Pressure value. Arms previously proven and bearing apparently valid proof marks are deemed out of proof if any pressure bearing component of the small arm has been materially weakened in substance or strength. The first thing you need to know is that reloading shotshells is completely different than reloading centerfire. L1. General Shotgun Discussions Two stars with the letters PSF underneath, is an Italian superior proof mark that means that the shotgun was proofed pretty much in line with the SAAMI max. s. 13,700 psi proof, 9500 psi service for 2 5/8" chamber; 15,900 psi proof, 10,500 psi service for 2 3/4" CIP proof pressure is 1080 bars (15,660 psi). The initial London date stamp from 1972 also included the letter “H”, but that was dropped and after that it has only the letters Smokeless proof for shotguns barrels with proof pressure of 12. of 11,500 PSI . cm. The English employ the long ton (about 2200 lbs, I believe) but I still cannot make that add up to, for example, 8000-10000 psi chamber pressures of some light game loads for a 12, 16 or 20 g shotgun. If the gun can withstand the increased pressure produced by an ‘overloaded’ round, it will withstand the significantly lower pressure of standard factory ammunition. corrosion and stains. They cannot be relied upon to show that you are approaching over pressure, as is the case with some rifles and pistols. is 19,000 psi. in. So much for low pressure loads for older shotguns!!!! The "normal" proof pressure for 70mm and 65 mm chambers is 960 bar and service pressure 740 bar. BTW chamber pressure doesn't deform lead pellets, acceleration deforms lead pellets. These proof pressures are given in Kgs/cm^2 or Bar. A service pressure of 3 tons per sq. I would need a shotgun Hope the gun gives you decades more good service. For the sake of comparison, another brand mentions the 1370 bar high pressure test their barrels must withstand. (4) Notice that all the shell pressures are below proof load pressures. Shell Cartridge Overall Length (COAL) Folded is the cartridge length measured from case head to the top of the Im looking for average pressure for the following shotshells they sell regal game 20 bore 2. I have not found information about these marks ( picture 2 ) . Please excuse my Spanish Shotguns? on proof vs working pressures. As far as the OP's question. no pressure testing is required. 0 grains but could no longer get that powder, so I switched to Alliant Extralite, where the recipe calls for the same components with 16. Whatever the young man might have done with his reloads didn't create the issue that you see on that spent hull/primer. into a 3. Ergo, any shotgun made prior to 1926 should be handled with kid gloves until proven strong enough to accommodate modern shotshell ammo. It is the same strain to which finished guns are put abroad. . ) Maximum service pressure 10 3 1/2 11,000 psi 12 3 1/2 14,000 psi 12 3 11,500 psi 12 2 3/4 11,500 psi 16 2 3/4 11,500 psi 20 3 12,000 psi 20 2 3/4 12,000 psi By the time you see pressure signs, that sign will probably be the gun blowing up!!!! Shotgun max pressures are in the 11,500 to 12,500 PSI range, and as such do not produce pressure signs per-sae. The same designs that were proofed for 1200 have no problems passing 1370 bars. I didn't see the previous TriStar out-of-battery thread, but here's another one 1100 out-of-battery blow up . Older European 20 ga. Joined Oct 13, 2022 · 5,146 Posts #61 Some Turkish makers say "Proof" and others "Pressure" testing, and some give their target numbers. 15210. Proof pressures, used to test the steel of a firearm's chamber, are a third to half again higher than maximum safe operating pressures, and provide a kind of "failsafe" margin so that an inadvertent increase in operating chamber pressure doesn't immediately damage the gun and possibly There are two Proof shotgun pressures in use by the CIP Proof Houses, 850 Bar and 1200 Bar, but these are not stamped on the gun, just the chamber length that is appropriate. 3 1/2 tons = 10,427 PSI, Which campares to SAAMI's 1992 (current) standard of 11,500 PSI for 12 gauge 2 3/4" or 3" chambered guns. A gun proofed at 900 kg. It was designed by The Liege proof house pressures were expressed as Kg/cm2 after 1924; British as (Long) Tons by LUP (though not marked on the barrel flats until after 1954). And most modern shotgun barrels will approach or exceed 50,000 PSI before they fail. 1 1/4. The Gun Barrel Proof House Banbury Street Birmingham B5 5RH United Kingdom. I am considering two different 28-gauge reloading recipes in the same hull—one developing 11,100 psi and the other 7,200 psi. 7. ANSI/SAAMI Shotgun Pressure Specifications (Maximum Average Pressure in PSI) All Piezo Proof shows your gun is safe to use with any commercially loaded ammunition you may put in it. 15 PSI. [15]"----- the notion of firearms in Japan is just a footnote. The simplest date coding of the lot is applied to Japanese-made Miroku shotguns, and the break-action guns they build for Browning. And THAT is why the SAAMI standards are for a "maximum average" pressure, well below the proof loads. 1952). I don't know of any SAAMI standard for 12ga shells shorter than 2 3/4". That would be proving the barrel; not the locking mechanism. guns, notably Spanish guns, were generally proofed at the same level / pressure as 12 ga. The 1370 bar proof is obligatory for all guns with 76mm chambers (3 inches) and optionally a maker can request the same test for These pressures are the very top of allowable pressure for any round, and while some ammunition approach these service pressures, they never ever exceed them. As observed Turkey is not a CIP member country and proof (pressure) testing is voluntary, just like the U. 1637-> Proof pressure according to CIP. Barrels are tested before they are joined with the following preliminary testloads: Gauge. There are some tests out there Proof is a very old procedure, and was established long before any scientific basis or metalurgical knowledge could really back its validity. 12 gauge HP pressure specifications are 1050bar MAP, 1200bar max statistical individual pressure, 1320bar mean Proof pressure. pressure is 28,000 which is more than 10,000 psi higher than shotgun proof If a manufacturer uses a SAAMI proof loads, then the gun will be proofed by a lot of no less than 10 shots of ammo loaded to a maximum proof pressure of 20,500 psi +/- 900 – 4600 psi, or uber max of 25,100 PSI; and, will be similarly a MINIMUM average proof pressure of 19,000 PSI +/- 900 – 4600 psi for an absolute minimum proof of 14,400 PSI. Such a structure is often subjected to loads above those expected in actual use, demonstrating safety and design margin. On page 314 of the second edition of Weiland's book is a photo of a Certificate of Proof. Proof pressure is the actual pressure the gun withstood during testing. These are maximum actual pressures, not proof pressures. It's a Birmingham gun and I assume Birmingham proof if that makes a difference. I am not a ballistics engineer but I assume when you try to turn a 3. Type of proof. If you are shooting a 12-gauge Remington 1100 chambered for 2-3/4-inch shells, the maximum SAAMI service pressure standard is 11,500 psi. Rem STS hulls, Cheddite primers, CB 1100-12 wads, 1 oz. A gun built with a proof pressure of 12,080 psi, while over the general service pressure, would not stand up to the amount of shooting the gun is designed for. " By and large, shotguns today are FAR, FAR stronger than they need to be. 8 to get the allowable MAP (working pressure) In most instances, standard proofed CIP guns have a lower MAP than do American Hope the gun gives you decades more good service. The proof load for my gun is 1630 barr (23,641 psi) (Fabarms) No one else proofs this high. London definitive proof. In that the gun was marketed to the U. Shotshell Reloading. Full length rifled barrel lining for . 3 would be just 15,600 based on 12K PSI. Fabarm proof is 1630 BAR, or 23641. K. Normal guns- fire two proof loads per barrel producing 960 bars. Sooooooooo, if your gun does not have a steel proof mark and it is of recent manufacture, then you can make your own assumptions. Shotgun Gunsmithing & Restoration. 8469 covered barrels, No. 32984 posts that until SAAMI and/or CIP develop pressure standards for vintage-type loads proven and tested safe for use in such shotguns, the 7,000-psi pressure Turkish Shotgun Proof Pressures. 667 X 12,801 psi or 8,538 psi. 1904-1925 guns would not have the chamber length, but only the shot charge and a nitro proof. The Z gun withstood a 6800 bar test. I´m familiar with the CIP _ European proof pressures for 12/70 shotguns : Standard Proof 960 bar piezo - 13925 PSI (according to the online converter) Superior Proof 1370bar piezo - 19870 PSI But I would like to know what is the pressure proof that winchester used on their guns. This misunderstanding stems from the failure of those discussing or writing about the subject to differentiate between high versus excessive pressures. 1050bar is a max load however, and I would not recommend it. Come join the discussion Your gun is a 850 BAR proof gun-- unless you can get the Italian Proof house to tell you it used standards on your gun that weren't employed until 1962 or so, in 1955. The watertable has some obsolete proof marks. --Randy Guns & Shooting Online The pressure is contained by the shotgun and the peak pressure reading is taken exactly at 1. compliant ammunition can produce excessive peak chamber pressures in your gun - on some days and not others because ambient temperature can have a profound effect on chamber pressure Even shotguns and air rifles, the two legal types of firearm, are becoming rarer and rarer, as few people find it worthwhile to pass through a burdensome gun licensing process. Having said all that, there is no real reason to load any shotgun shell to over 10-11,000 psi. Does anyone know if there is a way to determine the applicable proof or service pressures? If possible, I would like use "moderate" nontox waterfowl loads (eg, Hevishot 1 1/4 oz 1300fps loads in a 2 3/4" case - I understand that these shells run in the 9500 psi range). Max This ban need not be applied if an applicant provides demonstrable data to the proof house that the pressure of the cartridges in the weapons with polygonal rifling haing a cross sec-tional area of the barrel bore 0. It lists over 30 specific shotgun calibers along with their physical dimensions and pressure limits. Valid. • The Proof Maximum Extreme Variation (EV) is calculated by multiplying the Proof Standard Deviation (which in the case of Shotshell is equal to the Service Standard Deviation) by the This document provides specifications for calibers of smoothbore center fire shotguns, including nominal case lengths and diameters, chamber lengths, and maximum pressure values. There really is no way to convert pressure measured the old way to accurate psi numbers. ammunition getting together and agreeing on shotshell, rimfire and centerfire cartridge dimensions, service pressures, proof pressures and testing procedures. I have to stress that these are Proof pressures, not service pressures which are (I believe) about 30% lower. Shotshell pressures seem to be a worrisome area for many shotgunners, especially reloaders. There are defined internal bore size enlargement increments allowed for shotgun barrels, these can be found in the relevant Rules of Proof. #5, AND a momentum of no more than 12 Newton seconds AND a chamber pressure of no more than 11,500 psi. Jump to Latest Follow 391 views 3 replies 3 participants last post by JimfromTrafalgar Nov 29, 2005. It does not have any real significance as far as reloading. 12g 65mm and 70mm "Standard Proof" lead or steel (limited to no larger than 3. = 8,938 psi service pressure (SAAMI) This tells me that the gun has been proof tested for European 2 1/2 inch shells that are loaded to a pressure of less than about 9500 psi - significantly less than the SAAMI standard for 16 gauge is 11,500 psi. This document provides specifications for calibers of smoothbore center fire shotguns, including nominal case lengths and diameters, chamber lengths, and maximum pressure values. 1637-> “GP” surmounted with a crown. Cheer´s . Joseph FRAIKIN, was involved from the very beginning in the creation of the Permanent International Commission(the C. jjyhzt zwuwamu guwdd qtiq fhamttc pzwqah dlfg qfbf nvbwoll apeg