Shotgun chamber pressure chart (whether minimum or maximum bore, chamber size and headspace, amount of erosion at forcing cone and bore). Here is the formula for recoil, as written by E. The number for 2 1/2" would be in the 60s (64?) A forum community dedicated to Shotgun owners and enthusiasts including the Remington, Beretta, and Mossberg shotguns brands. _____ SAAMI Shotgun Pressure Specifications (Maximum Average Pressure in PSI) All Piezo measurements unless specified) Cartridge Maximum Average pressure 10 gauge 11,000 (all) 12 gauge 11,500 (all but 3 1/2" mag) Chamber Pressure. is just the right size for the large threads on shotgun bore mops and brushes. Using the SAAMI max pressure numbers, the PSI/CUP ratio is 1. 290 Smokeless is much more efficient, (21 grains vs 82 in this example) but as stated here many times the pressure-time curve is radically different. chamber pressure and it's effects. This measurement will tell you how much Dear Technoid: Now for the question. 1 3 of 5 Go to page. I have a Flues, that I shoot at times with Armusa 2. See the chart below for the standards, by gauge. Does the pressure limit depend on the different frame sizes between the various gauges or is it pretty much a 7500psi standard across the board? I have a chart showing the dates of chamber length changes but I can't find it now. 2) 2 x the Standard Deviation of the Mean (or 2-Sigma) TRADITIONAL Muzzle Loading Rifles & Shotguns. 12,500 . 50 caliber BMG using At the full down stroke the wad pressure indicator is moving to the 30 hash. I have no way to measure pressure, but a check of some (not all) of the reloading chamber pressure and it's effects. Second pressure trace chart. Discontinue firing at the first sign of excessive pressure or upon noticing a change in the report of the firearm. While today all data regarding factory load shotshell pressures are measured and reported in psi, there is still some shotshell reloading data kicking around in which pressures are measured and expressed in LUP. That's the name on the gun. 7] to force the case head back. Back in the day, I shot a lot of skeet with an older Browning Superposed I acquired with Purbaugh tubes. The vast majority of shotgun barrel blow-ups are caused not by the pressures developed by the shotshell load, but rather by obstructions in the barrel. For the last few decades, To answer the question posed by the OP, the chamber pressure has no relevant impact on the total velocity or the amount of recoil at a given muzzle velocity. 7 The mark shall be completed with gauge in mm, chamber length in mm and barrel weight. 005") The marking on it indicate 2. 110. 5 grains more (average), but are SAAMI MAP chamber pressures for all loads in . 1 – 2018 – Voluntary It is, and as far as RSI goes, they publish this themselves: "Shotgun load pressures will vary more than expected due to differences in crimp strength, powder column height and shot weight variations. The sub-ject of excessive pressure along with illustrations is included in most reloading manuals, and should be read before attempting any reloading. The manual Shotgun chamber length is important of course, but you will find that they seem to vary some, as do the length of the shells. 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 are. Never exceed maximum loads because excessive chamber pressure will result. And the problem is not just with pistol/shotgun propellants. Come join the discussion about optics, hunting, gunsmithing The U. Hearing & sound pressure has a lot to do with comfort. manufactures shotguns and shells to SAAMI (the Sporting Arms and Ammunition Manufacturers' Institute) specifications. I assume this was reviewed in his Nov-Dec. IMR-4831 is only slightly slower than IMR-4350 and most definitely faster than RL-19. With a good semiauto action soaking up some of that recoil, a 1 ounce load at that speed should be a kitten. Shell COAL Rolled – 3. A forum community dedicated to Shotgun owners and enthusiasts including the Remington, Beretta, and With that powder and powder drop weight, you could never exceed the SAAMI maximum chamber pressure of 11,500 PSI. It seems as if 760/414 is the worst in pressure spiking when the ammo gets really hot. For lower pressure weapons such as shotguns or smaller pistols, a lead Conversely, insufficient pressure may not propel the bullet adequately, affecting its trajectory and impact. Other people say that this is a wives-tale, and that the guns are safe to shoot modern 2 3/4 ammunition. 2. Smith. Headspace Dim – . S. My Kolar tubesets have the industry standard SAAMI pressure specs. Shotguns unlike rifles are low pressure so the laws of fluid dynamics that are troublesome in designing rifle brakes do not apply to shotguns. non pitted. When the new fangled, inflammable smokeless powder came into being a startling problem arose. Chamber pressure is not affected by the length of the The maxium SAAMI pressure limit is 11,500 for all but 3 inch shells in 12 gauge. In this section, Anyway, it made an excellent shotgun cleaning ram rod. 5" 410 chamber. It's not like . It states that the proof load for a 2 3/4" or 3" chamber carried 1 1/2oz of shot and pressures between 19,000 and 20,500psi. 1050 bar • energy (muzzle): 3048 Joule SAAMI Shotgun Pressure Specifications (Maximum Average Pressure in PSI) All Piezo measurements unless specified Cartridge Maximum Average pressure 10 gauge 11,000 (all) 12 gauge 11,5000 (all but 3 1/2" mag) 12 gauge 3 1/2" mag 14,000 16 gauge 11,500 (all) 20 Gauge 12,000 (all) Judging from the heavy volume of mail I receive, SSM readers have lots of technical shotshell questions. Presenting an approach for how the small ammunition manufacturer and technical handloader can best use SAAMI Voluntary Pressure Standards. I have presented published data that shows that this statement is not correct. Before proof the gun must have passed black powder proof and have stamp 1,2,3 and 5. Location of transducer. MAP all happens inside the hull, it is chamber pressure-- not pressure at gas ports. With that out of the way, let’s talk a bit about shotshell chamber pressures. and contain the data needed to establish those technical standards, the aim of which is to meet all the C. Same way with the two pellet load: the tested pressure drops with the use of a 300 grain Hornady sabot compared to a 240 grain Hornady sabot. 3 grains of powder will produce less chamber pressure and slightly more velocity than the 1 oz. Although I'm based in Denmark, I'm a soldier here with strong connections in the U. Chamber pressure alone cannot determine what cycles a gun, the ports are downstream and those pressures are not published (or even tested, in many cases). Notice that pressure, peak chamber or otherwise is not a component of recoil. 5”/65 mm chambers, and it’s important to remember that using cases that are shorter than the chamber and in particular with a The most common shotgun chamber sizes include 12-gauge, 20-gauge, and . the higher the chamber pressure will be Let's say that the correct load would have produced 11,500 PSI. The actual pressure is unknown. Sherman Bell, in article titled "Finding Out for Myself" Part V "Long Shells in Short Chambers" ( Double Gun Journal , Winter 2001) said that with loads that are sensible in a light 2 1/2 inch gun, he saw no dangerous pressure levels chamber pressure and it's effects. 500) typically register the low-pressure loads in rimfire guns and shotguns (though small-diameter copper crushers can be used too). Shotshell Reloading So my primary load data comes from the Lyman 50th manual along with information i get out of the hornaday manual and what i can download from the powder manufacturers all cross checked in an effort to not blow my face off What i am curious about is a gun/chamber is rated to a SAMI specification for pressure. Beretta 686 Chamber Pressure. Incorrect measurements can result in dangerous situations, so it is crucial to follow the correct procedure. The SI unit for chamber pressure is the megapascal (MPa), while the American SAAMI uses the pound per square inch (psi, symbol lbf/in 2) and the European CIP uses bar (1 bar is equal to 0. The barrels were literally the same diameter inside from the end of the chamber to the choke. There is no direct correlation between chamber pressure and energy delivered on target. Do you think the . Can you fire a smaller gauge shell in a larger chamber? It is possible to fire a smaller gauge shell in a larger chamber, but doing so may result in decreased performance and accuracy. 410 shotguns out there. Your gun was chambered for 2 2/4 shell, however, most makers held the chambering about 1/8" shy, in order to obtain better patterns. The action time (hammer hits the primer to peak pressure) is the yellow line, the pressure curve is the blue line. Check out the pressure a list of pressure standards for rifle cartridges. And their chamber pressure is about like a typical target load. , or twice the average maxium service pressure. @ This estimated pressure is technically over the 12,500psi SAAMI pressure specification for the 2. will the load I’m using have higher or lower pressure compared to the pressure generated by a 28 gauge modern shotgun I've read that the flues are meant to be shot with lower pressure loads. How is a pressure barrel different from a regular barrel? The answer is a Reference & Proof Ammunition Information. 325 x . Double gun shotguns - Side by Side shotguns, and over under shotguns - Including drillings, double barreled rifles, SxS double rifles, combination guns. Maximum average pressure for 2 3/4" and 3” shotgun shells will be 11,500 PSI +/- 900 There has been some discussion on some of the handloading forums that there is no longer enough difference in shotgun primers to keep one from being substituted for another. And there's a lot more to opening up the receiver of an O/U shotgun and burn rates for shotguns. Fact is that a Remington primer is milder than a W-209 and substituting it for the Winchester will lower the chamber pressure and probably lower velocity a tad. If it goes another 8" down a longer barrel it expands and cools that much more- so the gas pressure is lower and the sound is less. I think it's safe to say that if the gun Here’s some interesting ballistic pressure data comparing Fiocchi Magnum 616, standard Fiocchi 616, and Federal 209A. , which is about one and a half times the average maxium service pressure. 1 to 16. You can see Goex Old Eynsford 1 1/2 Fg is a higher pressure than Goex (standard red can) 1 Fg, all else equal. 20 grains VELOCITY = 1250 fps CHAMBER PRESSURE = 9200 psi Shotguns are proofed at much higher pressures than 10,000psi. Slow powders mostly have a lower peak pressure near the chamber but higher muzzle pressures. I'm on the hunt for an RSI Pressure Trace 2 system, which I understand is a great tool for measuring chamber pressure in both shotguns and rifles. I. s. (Courtesy of Johan Loubser) First, how many reloading articles have you read that contain the standard mantra "start with the minimum charge listed and work up as pressure signs indicate it is safe?" From testing tank guns and artillery, the pressure within the chamber varies with the chamber geometry and distance from the base. What is the maximum pressure that can be developed with Black powder 10,000 psi Votes: 1,025 40% 20,000 psi Votes: 522 21% Note: New & Revised Cartridge & Chamber Drawings not yet included in the standards can be found HERE. The powder amount in grains is from 15. Reply. Fed. 1 2 of 5 A forum community dedicated to Shotgun owners and enthusiasts including the Remington, Beretta, and Mossberg shotguns brands. There was almost no Z line at ignition. I measured the chamber end of the shotgun and found it to be about . 308 / 7. Load Shot weight, fps, psi, bar Remington Game Load 1 oz 1200 "1 oz. Tightness of barrel All Italian shotguns are Proofed by loads that are way in excess of any commercially available loads to be sure they are safe. This could be corrected by ADDING a few tenths grains more powder. top of the right hand column on this page, there is a chart indicating the proper setting. A 12-gauge shotgun’s bore is between 0. 0624 to . Fox Gun Co. 62 NATO, and . CIP sets a chamber pressure limit of 740 bar (10,733 psi) for "Standard Steel ammunition, and 1,050 bar (15,229 psi) for "High Performance Steel" ammunition. pitted vs. I understand that the pressures differed earlier in the burn-rate curves (fast vs slow burning I owned a 1923 12 gauge Flues one time, and it was a helluva lot beefier in the frame area, chamber, and wall thickness than the earlier ones I've owned. Come join the discussion about optics, hunting, gunsmithing, styles Pressure* ~ 12,700psi @ * This pressure is an estimate from NAMB using the actually velocity data to adjust my parameter for the program. Jump to Latest But I do have permission to use the SAAMI . Insert a piece of 80 grit sandpaper (I used a piece from an old sander belt) in the slot In measuring shotgun chamber lengths, the thickness of the rim cut and the length of the chamber body are combined into one dimension. In measuring shotgun chamber lengths, the thickness of the rim cut and the length of the chamber body are combined into one dimension. Come join the discussion about optics, hunting, gunsmithing, styles, reviews, accessories, classifieds, and more! Recoil energy comes almost completely from the velocity and weight of your payload (the shot). RSI Pressure Trace II Firearm Chamber Pressure System. Once the lead and wad have gone 24" the gas has expanded and cooled the same in both barrels. You may also want to consider using heavier loads This CUP is a long way under the 52,000 CUP maximum SAAMI pressure. None of the hand loaded slugs showed signs of over pressure. I own a 20 gauge "Remington 870 Express Magnum" shotgun whose chamber is built for 3" shells. All without the benefit of data, that didn't exist. com and request the lastest loading manual, Free. 410 bore. Maybe it was Oscar Gaddy. SAAMI Z299. load is reported to run 6810 psi, but actual pressure testing by Tom Armbrust showed it to be 7500 psi SO they must be using CIP data. ws be the shot charge weight. SAAMI Shotgun Pressure Specifications (Maximum Average Pressure in PSI) All Piezo measurements unless specified) Cartridge: Maximum Average pressure: 10 gauge: 11,000 (all) Chamber & Cartridge Dimensions. The ideal gas law basically states in our case that the pressure1 X volume in the bore area is equal to pressure2 X volume of the bore + the first chamber. A second example of a pressure curve (Blue Line) showing an initial pressure SAAMI pressure standard is established, with a significant margin of safety, bearing in mind some pretty sad . But other nonpropellant factors interact to determine a specific propellant's relative burn rate. A simple primer change can change pressures by 3000 PSI. If you have a older shotgun, consider reloading or factory RST ammo. Jump to Latest 81 - 100 of 100 Posts. American National Standards Published by SAAMI The SAAMI Standards are published to provide safety, reliability, and interchangeability standards for commercial manufactures of firearms, ammunition, and components. Check with the individual manufacturer for their policies. In which maximum pressure range will such a load be within? It’s hard to find pressure values on black powders loads, however it seem to me that black powder is in most cases low pressure compared to smokeless. Within firearms, chamber pressure is the pressure exerted by a cartridge case's outside walls on the inside of a firearm's chamber when the cartridge is fired. 209A 03513: 1251 (EV 14) 10,860 (EV 600) CCI I still get questions about pressure testing and load development. 13,500 . Pressure is discussed a great deal in a casual sense, but like most things Shotgun World General Forums. 7980"+- . SAAMI Product Codes and Supplier Information Final smokeless proof for breech loading shotguns. Modern shells produce much higher chamber Just got out my Holland and Holland chamber length gauge and measured the OD of it and it measures . The SAAMI proof pressure for this 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 The CIP standards, which carry the force of law which the SAAMI standards do not, are more complicated. I hope to see Morris and some of his staff in person this June and maybe get an update from them. that is in the pressure range of a 3. I know these systems might be available used in the USA, so I'm reaching out here in hopes of finding one. 10 gauge 11,000 12 gauge 11,500 (except 3-1/2 in. textOnPdp}} According to Alliant this will be approximately 8,600psi peak pressure in the chamber. To optimize your shotgun’s performance in these conditions, you need specially constructed loads perhaps upgrading to a medium burn rate powder. Loading 7/8 oz. 24. In my Lyman manual there are NO. The energy delivered on target is strictly a function of the velocity and mass of the The 2 9/16" chamber was reserved for 16 bore guns. volumeDiscount?. that chart is comparing apples to oranges not same to same. ) As the pressure continues to build, the case is forced so tightly against the chamber wall that it cannot move, but since we had a gap between the base of the cartridge case and the face of bolt or breech block—what we termed a little headspace—the case itself must stretch in the head region circled [Fig. Pressure is measured at the same point in all shells regardless of length, one inch from the breech face. 740″ so the terms “12 bore” isn’t actually correct even though it was a common term until recently. A forum community dedicated to Shotgun owners and enthusiasts including the Remington, Beretta, and Mossberg Look for proof marks on the barrel flats for gauge and chamber length. Pressure goes hand in hand with volume, it is a linear ratio(P1V1=P2V2). Operators of Piezo guns are warned that their operating practice can noticeably affect pressures. 308 chamber drawing for that project. The crusher method of determining chamber pressures has been around for a very long time and the methods used have become very rigid and standardized. Links to technical data and drawings for the newly SAAMI accepted Cartridge and Chamber designs not yet included in SAAMI Standards Primer burn rate chart? Depending on the particular load, and the exact data it was developed with, and depending on the chamber pressure it developes, experienced reloaders can and do sometimes substitute primers, other than the ones specifically called for. i. I recently became aware of chamber pressure warnings/advisements when using sub-gauge tubes, specifically with regard to 20 gauge tubes. In the U. 089 psi. There are many loads for 12 gague shotguns that are in the 6,000 psi range that produce excellent patterns. No method of measuring chamber pressure is 100% accurate. The 12 bore was usually 2 5/8" or 2 3/4". TATV Canada. But some where along the line they must have changed the loading data for 700X. 750" and 3. Reloads coming out of my MEC 600JR were too tight to chamber, even though they fell within SAAMI standards. I have checked the chambers on quite a few Smith 12 bores and found them to be 2 3/4". 38-55! I find fast powders may have a higher peak pressure at the chamber but much lower muzzle pressure. 3. Any number of things can,and will,have an effect on chamber pressures. A. The length of the forcing cone is not included in the specified chamber length. Lymann's say's 11,400psi is max but yet i see recipes that go A forum community dedicated to Shotgun owners and enthusiasts including the Remington, Beretta, and Mossberg shotguns brands. Smaller shot would distribute the outward friction of the inertia of the shot charge to the barrel more evenly because of more contact points between the small shot and the wad cup wall; but larger shot, while having fewer contact points, would generate more force on each contact . 1Oz of shot will give you around 1070-1120FPS, chamber pressure in the 4-5K range depending. Chamber Pressure p. I did not say any particular gun is safe Shotgun World General Forums. Come join the discussion about optics, hunting, gunsmithing, styles, reviews The Chamber Gauge shows the chamber length is shorter than 2 3/4″. d. You can go onliune at www. However, one gunsmith I spoke to said this number is a guide that will be safe in any 12 gauge shotgun, but that modern guns from Beretta and Browning should be able to handle more pressure (14,000 Pressure problems because the plastic shells open longer than the older paper roll crimps. to I am unable to find Dave's quote "The hotter the primer, the higher the chamber pressure will be with ANY POWDER" in any reloading manual. With shotshell chambers varying in length and diameter, exact pressure cannot be predicted. Given all the details of the original question, mixing up shot velocity and peak pressure is a big mistake. Uh, pressure is going to be evenly distributed across the bottom of the wad seal. 25. By TATV Canada. It isn't akin to chamber and cartrigde sizes for centerfire rifles. Chamber length determines the maximum allowable length of ammunition that can be safely used in your firearm. crushers don’t register peak pressure accurately because the flow of copper is slower than the change of pressure in the chamber. Proof loads are usually 15,000 p. 11000 chamber pressure " Federal Game Shok In this graphic portrayal of average and dynamic V/C ratio, the plots diverge when chamber pressure exceeds safe levels. Requirements for the proof of small arms. I'm loading the Lee Drive Key slug and was wondering how much the choke affects the chamber pressure? the reason I'm asking is, the slugs in wad fit through my barrel really well but I can't get them through my IC choke. Is it safe to fire a larger gauge shell in a smaller chamber? The peak pressure and temperature is the same (chamber pressure). General Shotgun Discussions Using 2-3/4 inch shells in short chambers has been shown to only “slightly” raise the chamber pressure. However, I can say with certainty that unless you have an obstruction of some kind blocking the bore, the highest chamber pressure will be before the shot charge has traveled 3 Waterengineer, Your Ithaca SxS is a Flues Model. Chamber. Here are some common ones. According to this chart Calculating Barrel Pressure and Projectile Velocity in Gun Systems | Close Focus Research - Ballistic Testing Services a 28 gauge shotgun generate max 12,500 PSI. 14,000 16 gauge 11,500 20 Gauge 12,000 28 gauge 12,500 . Normally measured by means of a piezoelectric pressure transducer or a copper crusher. Headspace – Rim @ . 99 $14. Note: The purchase of Reference and Proof Ammunition may be limited to individuals and businesses with legitimate need and proper controls in place. 6. 410 are: 2 1/2" Chamber 12,500 PSI 3" Chamber 13,500 PSI Anyway, I found a chart of low pressure 10 gauge loads. Looks like the Fio Mag 616 are hotter than Fed 209A in this tested data. Say the loader is curious and wants to know the ballpark PSI. 357 magnum, . 45 ACP, . Pressure limits (actually, industry-wide voluntary standards) are set by SAAMI. Keeping your pressures between 9 and 10,000psi keep them burning cleaner. imrpowder. By the time the wad is 1/4 the way down the barrel, the pressure will be below 40% (SWAG) of max. Newly Accepted Cartridge and Chamber Designs. What does peak chamber pressure have to do with cracking the wood?? Recoil cracks old wood not chamber pressure. 5" shells in it, they are available from different suppliers. Consider that I (and many others) sometimes shoot 20 gauge loads in our 12 bore shotguns with the assistance of the very short Seminole Chambermates. When you reload what max chamber pressure do you feel safe using. 99 Coupon Code {{BNApp. 4. 1 5 of 5 Go to page. Lot-to-lot variations, design changes, or You didn't mention what the chamber length was on this gun, alot of these older gun were 2 1/2" or 2 5/8". Type and style of the hull used,primer brisance,burn rate of the powder,ammount of powder used,style and construction of the wad,weight of shot charge,length of the forcing cone, size of the chamber it is fired in,bore diameter of the barrel. (20) Proof Load means the load required to develop proof pressure on firing. I suspect that 20 gauge loads will work quite well at a lot lower pressures than you might suspect. One common question I receive goes like this. loads using 15. loads noted on the PP bottle/jug. Seems to mirror the filler/no filler discussions for a . So there won't be a difference in the recoil you will feel between a high and a low chamber pressure load. Sporting Arms and Ammunition Manufacturers’ Institute, Inc. that means to stick with the 2 3/4" and 3" chamber pressure limit of 11,500 psi even when loading those size The commercial ammunition manufacturers have for many years used special pressure rifles that use the chamber pressure created by the burning powder to crush a small Weatherby PA-459 Shotgun . Data has to start somewhere, and there are safe ways to go Muzzle pressure and chamber pressure are like the secret sauce behind a gun's performance. The chamber refers to the part of your shotgun where the cartridge will sit, and the chamber size refers to the length of the fired shotgun cartridge. For these tests Shotgun Chamber Gauge Handle Brownells # MFR # UPC $6. 005 inch under sized, see specs below. The tables have been approved by the C. In shotguns Calculate the volume of the barrel bore including the chamber. Lowry. Every gauge and size of shotshell has a maximum pressure. Once again, the pressures in the smaller bore shotguns will be higher. 720″ and 0. 5" 12 gauge 10 Gauge 3 1/2″ MAP (PSI) – 11,000. And pressure inside the barrel as the shot leaves the barrel is directly related to report loudness. 5. At that moment in time, the wad has hardly moved. 111 Videos. . The i. For the metallic reloaders starting In Brophy's book "Plans And Specifications Of The L C Smith Shotgun", the drawings and work charts indicate the chamber length for 12 bores to be 2 3/4". 000" chamber lengths and when inserted into a chamber it reads the chamber direct at the appropriate length. , voluntary pressure standards for rifle cartridges are set by SAAMI, a member of ANSI. Depending on the weather, it could change by a thousand units of pressure. Worry not. The answer quite simply is the chart actually applies to both chamber and shotshell maximum pressures. 56 NATO, . And pressure questions continue to lead the way. J. My friends at Accurate Powders / Western Powders inform me they have seen 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. game loads are loaded to approx. To be safe, check every chamber length with a chamber length gauge. All 2 3/4 12-gauge ammunition manufactured in the U. dogchaser37 · Premium Member. 70mm case length: Guns with a chamber length of 2 3/4” or longer, nitro proofed to a service pressure of 3 1/4 tons per square inch (900 kg per square cm) 67 mm case length: Guns with a chamber length of 2 1/2” or longer, nitro proofed to a service pressure of 3 tons per square inch (850 kg per square cm. If I have identical wads (dimensionally), but one weighs more, will the heavier one produce more pressure? My wife (and shooting partner) bought me a new digital scale and I happened to have some Winchester and Claybuster 20ga wads. VV wasn't so bad and Hodgdon 322 spiked pressures too. (Minimum chamber dimension as it nears forcing cone is . 5 a bunch of guys building successful shotgun chokes for 125 years. I asked Lee Precision about it and they said "the drive key slug can be safely fired through an Improved Cylinder choke". 2 for pressure guideline interpretation description. In actual use, powder can burn faster or slower than its rating due to the diameter of the bullet, the size of the case, chamber pressure but the pressure peters out quickly so the end Pressure and Velocity of Shotshell Ammunition for the Use of Commercial Manufacturers. 15384600 36,900 * In measuring shotgun chamber lengths, the thickness of the rim cut and the length of the chamber body are combined into one dimension. You could also use The problem I have is that I don’t know for sure what’s the maximum pressure of my load, so I don’t know what I should compare with. 2013 article The Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives transducer "Maximal Statistical Individual Pressure" for 850 BAR = 12,328 PSI, for a "Maximal Average (Service) It is also true that a lighter than average load may reduce your chamber pressure to a point where the proper burning cycle cannot be concluded. • mean chamber pressure: max. Save Share Like. D. H. back in the late twenties I believe it was with then current Dupont FFFG black using 3 drams under 1¼oz shot showed a pressure of near 9,000 psi, higher than what Lyman recorded in their Modern US made shotguns have the chamber length marked on the chamber area 800-493-4114; REQUEST INFO; ENROLL NOW; SCHEDULE APPOINTMENT; MGS SHOP CART. Sherman Bell, in article titled "Finding Out for Myself" Part V "Long Shells in Short Chambers" (Double Gun Journal, Winter 2001) said that with loads that are sensible in a light 2 1/2 inch gun, he saw no dangerous pressure levels produced. ) 12 gauge 3 1/2 in. Prior to around 1900, shotgun chamber lengths varied consid-erably from manufacturer to manufacturer, often resulting in odd fractions. 410 has greater recoil than the 12 gauge? :shock: Even within the same gauge, pressure and recoil are not linear in their relationship. If the chamber is a bit undersize a gauge made to "industry" standards will not go in to the true depth of the chamber. and black powder substitute load cited above smashes the rules of what you can use in your modern smokeless powder shotguns and deer-hunting slug guns. 13 Likes. For those who use or are interested in the pressure developed by RST Shotshells the following info was provided on request by RST in 2017. Go. 5" loads, keep the pressure down to less than 8500 psi and you"ll be ok. If they can even define what low and high pressure mean in a shotshell. Jump to Latest 41 - 60 of 100 Posts. Lyman's fifth is the manual that this forum recommends Shotgun max pressures are in the 11,500 to 12,500 PSI range, and as such do not produce pressure signs per-sae. Not too worried as the sales clerk says I have loaded thousands of shotgun shells with the Federal 209A primer with excellent results. In fact, I would say that the areas of greatest ignorance and misunderstanding That's why the chamber pressure peaks almost immediately and then drops off rapidly. A good gun really should be proved at 20,000 p. Original chamber is 2 9/16s. P. The data is for 1 oz. All you need to do is solve for the pressure2 to find what to approximate the first chamber pressure at for the design. 1) A string of 10 fired loads must average at or below the SAAMI MAP (maximum average pressure) as established for a guns Gauge and Chamber Length. 15-Pellet Lead 4 BK @ 1,200 fps 1-oz Lead Rifled Slug @ 1,200 fps (1) Refer to ANSI/SAAMI Z299. 4 grains in a Winchester hull. 410 shell produces greater chamber pressure than the typical 12 gauge shell. Shell COAL Folded – 3. If all of this verifiable, independently SAAMI Pressure Chart. In general, the nearer the base, the higher the recorded pressure nears the true Once enough pressure is produced inside the case to cause it to swell and touch the chamber walls, the conformal transducer accurately measures the chamber The chamber body itself has a taper of about . Sometimes chambers were cut with slightly worn reamers giving a slight undersize chamber. That's why he suggested it. 4 extra grains MIGHT bring the chamber pressure to 13,500 PSI. Using 2-3/4 inch shells in short chambers has been shown to only "slightly" raise the chamber pressure. For example, they have IMR-4831 as being slower than RL-19. The first Gun Club trace from the left side, was at peak pressure 0. (22) Proof Pressure means the mean maximum pressure required by RST Shells Pressure Charts. He showed that the chamber pressure to which the shell is loaded is more important than its length. depending on the firearm type. I use that to push the tampons through the bore, using them much like patches The Sinclair Chamber Length Gauges are designed so the handloader can determine the true length of his rifle's chamber when measuring from the bolt face to the end of the chamber's neck. The typical . A forum community dedicated to Shotgun owners and enthusiasts including It also tells you how much pressure your gun is built to handle. Here's how they play a crucial role in suppressors. The SAAMI New Cartridge & Chamber Maximum Average Pressure (MAP)(1) = 11,500 psi Instrumental Velocity(2): 15/ 16-oz Lead Shot @ 1,145 fps Crusher pressures not established. I think that down barrel pressures may be more important when shooting old Damascus guns where the barrels get quite thin near the muzzle. Jump to Latest A forum community dedicated to Shotgun owners and enthusiasts including the Remington, Beretta, and Mossberg shotguns brands. SAAMI Shotgun Pressure Specifications Shotshell Maximum Average Pressure (MAP) in PSI. Come join the discussion about optics, hunting, gunsmithing, styles, reviews, accessories, classifieds, and more! At the other end of the chart is the Cheddite 209 with the lowest velocity averaging 1217 FPS with a variation of just 20 FPS. These include case capacity and Chamber pressure rating? I've seen references to the rated chamber pressures of different guns here, some supposedly as high as 14,000 PSI. Chamber pressure decreases in short order in a shotgun. The shotgun barrel is divided into five areas: the chamber, the chamber-to-bore forcing cone, the cylinder bore, the choke forcing cone and the choke. Jump to Latest 21 - 40 of 100 Posts. Jump to Latest SAMMI lists the maximum safe chamber pressure of 12 gauge shotguns with a 3" chamber at 11,000 psi. I guess that the pressure at this instant could be the same for both loads, but I doubt it. Current Levergun Don, I can't give exact answers to where the chamber pressure is the highest because it depends on several factors such as type of powder, amount of shot, length of forcing cone, etc. 0764. A forum community dedicated to Shotgun owners and enthusiasts including the Remington, Beretta, and Mossberg shotguns brands. a rimfire obviously generates factory ammo chamber pressure will vary from lot to lot. Obstructions can take the form of lodged Here is a link to Hodgdon's Burn Rate Chart. All of the parts of a Shotgun Pressure Specifications. 1 MPa). RSI Pressure Trace II Firearm Chamber pressure, retesting published loads, what is actually getting tested and what the data means when loads are sent in to be tested, cannister powder lot variation, primer lot variation and possibly what this all means for your shotgun. W be the gun's total weight V be the gun's recoil velocity. 7965". You can also look up loads online. 1 Then things got real complicated in certain 12 ga specs since there are now rifled shotgun barrels! Take the example that there are now rifled shotgun barrels on rifle actions lke the NEF rifle actions The maximum pressure is exerted at the breech end in the firing chamber and decreases further down the barrel tube. The stamp represents a pressure, and if converted to an English pressure it is around Some tubeset manufacturers MAY recommend you stay away from max pressure loads-- but I have never seen it published when researching Kolar and Briley tubesets. 5 MS faster than the rest. Come join the discussion about optics, hunting, gunsmithing, styles, reviews, accessories Cartridge and Chamber Designs Standardized by SAAMI Note: Current Cartridge & Chamber Drawing doc uments are contained within the SAAMI Standards. This will force the charge and shot to be forced through a constriction in the barrel, causing excessive pressure. That pressure created in the chamber of a firearm by the expanding propellant combustion gases. 44 magnum, . dialogAddCart?. Final proof of rifled long guns with a 30% excess pressure. This is noted in 1907, 1922 and 1935. Then if you go up to the High Shown in the table below are a few sample calculations of both Projectile Velocity and Barrel Pressure for the 9mm, . As luck would have it, most shotgun crude way to measure burn rate but that’s how powders are ranked in burn rate charts. As the volume increases, the pressure decreases. He said there was no CHAMBER PRESSURE = You might work with a recipe like this: HULL = 12 ga, 2-3/4" HS/AA or Rem STS PRIMER = Win 209 POWDER = Hodgdon UNIVERSAL, 24 grains WAD = WAA12114F / CB114 / DR-12 (1 1/4 oz) LOAD = Buckshot, 00, 9 ea, 1 1/4 oz / 481. 410 pressures are low, compared to other bore diameters. 100% . (21) Proof Master means the person or persons, who, for the time being, carry out the duties of Proof Master of the Proof House to which a barrel or arm has been submitted. 5 grain incre-ments as accuracy needs and pressure indications permit. Following is the first shotshell pressure chart I found via google. When is a gun out of proof? A gun is considered ‘out of proof’ when the barrel is materially altered or damaged (for measuring chamber pressure. Proof pressure is 12. 1 ounce of shot, at 1150 FPS, is constant. SAAMI Shotgun Pressure Specifications (Maximum Average Pressure in PSI) 10 gauge 11,000 (all) 12 gauge 11,5000 (all but 3 1/2" mag) 12 gauge 3 1/2" mag 14,000 16 gauge 11,500 (all) 20 Gauge 12,000 (all) 28 gauge 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. Metalic cartridges operate at very high pressures. 410 Bore 2 1/2 in. A worked out hypothetical 3-Sigma example for chamber pressure: PSI's for a hypothetical 6 shot string: 1) 11,000 PSI 2) 10,650 PSI 3) 11,780 PSI 4) 12,100 PSI 5) 9,670 PSI 6) 11,100 PSI I suspect Boss is going to say they You do need adequate backpressure to sustain combustion, but that varies by powder. 99 - $12. shotguns are known for having tight chambers. January 14, 2019. That isn't quite right. Measuring pressure this way is expensive and tedious, but works well if done correctly. Shoot 2. 70 is 2 3/4". (remove the extractors before honing). 223 / 5. takes a heckuva lot of pressure before a shotgun barrel will actually blow up from the pressure developed by the shotshell load itself. The following bullet ballistics chart shows what happens (. Newton's Law dictates the amount of recoil, and the burn rate of the powder, not the maximum pressure generated, controls the velocity. The number 76 means 3". The small ammunition manufacturer and the serious handloader are more and more able to get reasonably accurate chamber pressure readings from strain gage pressure test equipment. Most other countries in the world follow the standards of Europe's CIP (Commission weight—without ANY evidence of excessive chamber pressure— the powder charge weight may then be increased in 0. If you have a jug of Perfect Pattern the data is on the label. 005" per inch. Factors Influencing Chamber Pressure The type and quantity of gunpowder, the bullet's seating depth, the integrity of the cartridge The larger bore guns and smoothbores drop down below 10,000 PSI. Eibar. 1929-1931. Fit of transducer in barrel. Joined Mar 6, 2009 · 12,742 Posts How much recoil would you get if you lit off a The Fiocchi 16GT 1 oz. Virtually the same muzzle velocity, but check out the peak chamber BTW chamber pressure doesn't deform lead pellets, acceleration deforms lead pellets. As we mentioned, there are old 16 gauge shotguns with 2. 410 Bore 3 in. 8900. Prior to around 1900, shotgun chamber lengths varied consid-erably from manufacturer to manufacturer, often resulting in odd As a responsible firearm owner, it is important to understand how to accurately measure the chamber length of your shotgun. In fact, chamber pressure has nothing directly to do with recoil. The Claybuster weighs about 3. " It is sold as "Rifle Chamber Pressure Testing Hardware & Software" after all. Further, I cannot find your "simple chart" to primer substitution published in any reloading manual. About ten years ago, somebody on Double Gun BBS had some kind of chart to measure your Flues and see if it was good to go with light modern smokeless loads. loads. As I mentioned, break action shotguns have been produced for a long time. They can be found HERE. Also It's best to leave the chamber open with the shell laying on the magazine follower instead of in the chamber, especially after several shots in a fairly short time. 1 Comments. iljdbxm iwtvmb kbbgug ylqlkx fcxvo zsi evi uakg fagvrl oipaazj