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AIU You have 3 or 4 of the "most experanced with excessive pressure" (one of them does distructive testing of firearms for a hobby) people on this board nervous with your loads, what does that tell you? | |||
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AIU,
Your loads are well into the 70,000 psi range! Your ability to get multiple reloads stems from the FACT that your statistical range of pressures on those loads has not yet exceeded the elastic limit of the case. Your 06 case should take at least 77000 psi before it suffers ANY dimensional change (not necessarily a blown primer). Your 300 Winnie will take more. The more important question you should ask your self is how much stress is my load imparting to my barrel tenon and how many shots at that stress level can my barrel tenon take before it suffers a fatigue failure? (fatigue failure in laymen's terms is explosion). Ignorance is bliss, man. Do whatever you want. ASS_CLOWN | |||
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AC, how would you answer that question, given the information I've provided regarding the 3006 AI and 300 WM loads? Also, what do you mean by barrel tenon? Have you ever experienced or witnessed fatigue failure in a modern bolt-action rifle shooting ammo in the 70 to 75,000 psi CIP range? Thanks ahead of time for your responses. Regards, AIU | |||
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AC, if this is true, why must we resize all cases after each firing, including those with mild reduced loads? It seems to me that brass has imperfect elastic properties, since it never returns to 100% of its original shape - hence the need to resize after each firing, even with light loads. However, the harder it's "hammered" by higher and higher chamber pressure the more it is deformed - that is, the more it flows. For example, extracter marks become incrementally more apparent as powder charge and pressure increase. Likewise, primer pockets deform more and more as powder charge and pressure increase. From my observations (in concert with the NECO internal ballistic program) and from what I'm able to glean from PO Ackley's work and conversions with a sundry of Speer, Sierra, Hornady, and Nosler ballistic engineers (i.e., the guys who put the reloading manuals together), primer pockets will deform at from 75,000 to 80,000 psi to a level allowing gas leakage - that is a blown primer. According the NECO program, given my setup, at 77,000 psi I should witness 3263 fps with a 165 gr. NBT using 69.0 grs. of Reloader 19. At this velocity and powder charge, over 1/2 of the time, I'll blow the primer and find serious extracter marks and get major sticky bolt lift. But, you're right the major issue is - CAN THE GUN TAKE IT and FOR HOW LONG? This gun is a custom built Rem700 with a trued/squared-up action, a Sako extracter, a 26 inch Hart match-grade stainless steel barrel (0.75 inches diameter at the muzzle), and a HS precision fiberglass stock. How many rounds at 77,000 psi can this gun take? I'd be interested your and others opinions on this? Regards, AIU | |||
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AIU,
The only part of the case which DOES NOT yield is the case head. The case head is the first ~ 0.2" of case and comprises the rim and extractor groove, as well as, houses the primer. The case head DOES NOT yield during firing. If you do yield the case head, you will ultimately blow a primer. Your -06 load is running around 72 ksi for your information. Like I said you can do whatever you want. Just don't be surprised when something bad may one day happen. The barrel tenon by the way, it the portion of the barrel extending into the reciever. It has the thinnest wall section and typically is the area first to go. Once your barrel lets go, your receiver is right behind. Then goes your hand, arm, face, etc, etc. If you do not know the answers to the questions I asked you, I strongly recommend you revert back to the loads recommended in load manuals. But like I have said three times now, you can do whatever you like. Here is a little friendly technical info. SAE4140, which is what most chrome moly rifle barrels are made of, doesn't fatigue all that well (and neither does 416 stainless). ASS_CLOWN | |||
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You are endangering other posters. Stop posting data that makes you LIABLE for damages to people. jeffe opinions vary band of bubbas and STC hunting Club Information on Ammoguide about the416AR, 458AR, 470AR, 500AR What is an AR round? Case Drawings 416-458-470AR and 500AR. 476AR, http://www.weaponsmith.com | |||
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AC, are you saying that gun manufacturers (which have been working cooperatively with the military for decades, even centuries) have opted for steel that doesn't "fatigue all that well." I'm flabbergasted! If I were making a machine gun, I'd use the best grade fatigue-resistant steel I could find. Machine guns, especially those in fighter airplanes - where sustained long-range performance is critical - must be operating at significant pressures. These guns are built to fire hundreds of thousands of rounds, and from very,very HOT actions and barrels. As a pilot or soldier I don't want my gun to wear-out, let alone blow-up from fatigue failure. Think of the devastation to the airplane - blow itself out-of-the-air! AC, I'm still really interested in your estimate of how many rounds can be fired at 77,000 psi from the custom bolt-action rifle I described before fatigue failure occurs at the barrel tenon. (By the way thanks for explaining that term.) This is very important, because many hunters may only shoot a handful of really hot loads per year - maybe only enough to sight the gun in and kill one elk (i.e., 10 or 15 rounds total per year). I doubt if I've shot 500 rounds (most at low pressure) in either the 3006 AI or 300 WM. This year I'll shoot the 300 WM ~15 times, the 3006 AI ~15 times. I agree with your estimate of the pressure I may be operating at - that is, ~72,000 psi, given 3200 fps, 165 NBT, R19 powder, and a 26" barrel. You must be using the NECO program as I do, because that's exactly what the program predicts. You'll also note that the NECO program predicts by using Norma MRP you can achieve 3200 fps at about 65,000 psi. I've tried Norma MRP, but I've found that it behaves as a "faster" powder when compared to R19. I've tried R22 and V560, and, likewise, both behave as a "faster" powder compared to R19. Why do I know this? With MRP and the other powders - in the 3006 AI behind a 165 NBT - I encounter significant pressure signs at velocities less than when the same signs occur with R19. Yes, in my 3006 AI R19 appears to be acting as a slower burning powder than Norma MRP, V560, and Reloader 22 - go figure! Powder manufacturers claim that powder burn-rates vary somewhat according to conditions - that is, from caliber-to-caliber, bullet-to-bullet, gun-to-gun, etc. And, that powders "relatively" close together on the burn-rate charts may flip/flop. Maybe that's happening here. Some authors have touted R19 as "near perfect" for the '06. Possibly, R19 really "settles down" in the '06 AI. I've similar findings for W760 - another great powder for the '06. Also, I may have a relatively slow lot of R19 - I bought 8 pounds, and I'm still have 6 pounds left. Finally, at 72,000 psi I'd be ~11% above 65,000 psi. If the 300 RUM can "safely" operate at 65,000 psi (Laseroni loads to 69,000 psi), why can't the 3006 or 300 WM? - my guns are just a good as those made for the above calibers. In fact, I'd argue that my guns are very likely better than off-the-self factory guns. (The gunsmith is a famous benchrest rifle shooter and gunsmith, whose work and achievements are among the best available in the USA). | |||
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There is an interesting concept in many mechanical engineering handbooks, called the log S/log N curve. The general idea is to determine roughly how many incidents (N) of what magnitude of strain (S) are required to cause 50% of items to fail catastrophically. The basic idea is that if you plot this on log-log paper, you get a straight line. Hence the name log S/log N. Running a gun at SAAMI pressures, N is so high that your chances of a catastrophic failure within the accurate lifetime of a firearm are very, very small. Run S up, as you are doing, and N becomes exponentially smaller. Nobody that I know of knows the answer to your question about how much smaller N is at 77,000 PSI, but we can say that it is very much smaller than it is at 60,000 PSI. Just because you poke a bear three times, and he does not respond, don't assume that he will never respond. By running the pressure up, you also increase your risk of a stuck case, which is not a nice thing to have if you're trying to take a second shot at the biggest elk or the most angry bear you've ever seen. Prove all things; hold fast to that which is good. | |||
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There are some factors that haven't been discussed: Case Head Design-some cases have stronger case heads than others. In comparing a 222 Remington case head to a 223, one quickly discovers why the 222 operates at 46000 PSI and the 223 operates in the 55000 PSI range. Case Design- Ackley Improved designs grab the chamber walls so well that there is hardly any pressure exerted on the bolt lugs, i.e. backthrust. This in effect eliminates one of our excessive pressure indicators, heavy boltlift. One now has to wait for either a loose primer pocket, or a stguck case. Both of these occurr at a pressure level that cannot be predicted. The reason is simple: not every brass case is the same. Some cases will fail sooner than others. Staying below max ensures that the likelihood of failure remains low. Going over max increases the likelihood of case failure exponentially, as was stated before. People have been injured by case head failure with standard pressure loads, just because the case had manufacturing flaws. It is a risk I'm not willing to take. But if you want to risk your health, please tell your guide to stay some distance away so that he isn't injured. | |||
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My answer to that is that "all rifles are individuals, and what may be way over maximum in one may be quite mild in another, and vice-versa", (to quote Bob Hagel). "Bitte, trinks du nicht das Wasser. Dahin haben die Kuhen gesheissen." | |||
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AI, AC MAY indeed have witnessed a catastrophic failure of the steel in a modern rifle barrel or action. However, if he did, it was due to some fault in the steel thereof, and not from years of firing ANY load that did not expand the primer pockets of the brass cases that were fired in it! The brass case is the weak link, not the steel from which the rifle was made! "Bitte, trinks du nicht das Wasser. Dahin haben die Kuhen gesheissen." | |||
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Denton, Ralph, and EL - you all make very good points. At the levels I'm shooting (i.e, somewhere between 65,000 and 72,000 psi) I don't think I'm at much risk of fatigue failure of the gun - I don't shoot at these pressures very often (i.e., only for long-range big-game hunting). This is especially true given the quality of the bolt-action guns, the slow burning powders I use, the use of chronographs + NECO internal ballistic program, and the meticulous care in measuring/inspecting every charge. I use the highest quality components I can buy, including benchrest rifle primers. As you mentioned, basically I'm pushing the limits of the brass case - the limiting factor. My major concern is a stuck bolt, while hunting for that trophy, then watching the bull or buck of a lifetime walk over the hill without being able to fire a second shot. Actually, I carry a 3-piece cleaning rod at all times - actually all of us should. Why? - because case failure could happen anytime, even with a "safe" load. By my calculations the loads I'm using are ~3 grains away from a blown primer, and I'm not certain I could freeze the bolt with the slow burning powders. | |||
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But the extra FPS are worthless unless the accuracy you are achieving is extraordinary. | |||
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"300 WM - 26" barrel, custom-made Rem M700 83 grs. Reloader 25 with 180 gr. Nosler BT Oehler chronographed (3 screen) = ~3300 fps. Note: An awesome, maximum! load - multiple one shot kills on elk at up to 415 yds. Alliant powder lists maximum for R25 in 180 gr. bullets in 300 WM at 82.3 grs. Sub MOA accuracy at 100 and 300 yds. Never shot at 500 yds." That's some serious velocity for a .300 Winny. I load my .300 Ultra Mag with 96 grains of RL25 and using the same bullet I only see 3365fps across the chrono. | |||
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Ralph is exactly right. I'll even take it one step farther. The extra FPS may be worse than worthless, they may be counterproductive. For many bullets, penetration decreases as impact speed increases beyond a certain point. Yeah, it's counterintuitive, but I have the independently obtained numbers in front of me. The best bullets I know of have constant penetration over a wide range of impact speeds. So it doesn't matter if you wring an extra 200 fps out of your gun...you'll still get the same length wound channel. Prove all things; hold fast to that which is good. | |||
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Why not limit shooting to 300 yard or less? Four hundred is too far to be shooting big game. While you can hit something as large as an elk at that distance, can you place the shot that well and will it have enough energy to take the animal down immediately? | |||
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Papershredder, you're right that is serious velocity. In my opinion, the 300 RUM and 30-378 are seriously overbore. Play with the NECO internal ballistic program and you'll see what I mean - those gas guzzlers are not that efficient. But, newer slow burning powders are coming along that will likely make these monsters more efficient. Have you tried Retumbo? That load in my 300 WM (heavy Hart match-grade barrel) has one MOA accuracy - meaning I should be able to hit a 6 inch circle at 600 yrs. corresponding to the vital area of a deer. An elk would be easier. With modern laser range finders and a B&C reticle in 3.5-10x Leupold makes this shot possible - that is, if I don't get screwed by a cross wind. | |||
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That load in my 300 WM (heavy Hart match-grade barrel) has one MOA accuracy - meaning I should be able to hit a 6 inch circle at 600 yrs. corresponding to the vital area of a deer. An elk would be easier. With modern laser range finders and a B&C reticle in 3.5-10x Leupold makes this shot possible - that is, if I don't get screwed by a cross wind. AIU, You are going to find that 1 moa does not necessarily transfer to a 6" group at 600 yards, there are a lot of variables going on here! You recognize that wind is one of them, but definately not the only one. Also, while gizmos like graduated recticules (have a couple myself) and rangefinders can be handy tools, the person who relies on them often does not do as well as the person with just a duplex on a fixed power scope, or irons for that matter, but gets out and uses his gun enough he's intimately familiar with where it shoots. 180 grains at 3300 fps, how can you shoot that enough to get familiar with it and not develop a flinch? Maybe not a big flinch, but one that definately rules out the 600 yard elk, which is your stated purpose for risking life and limb, or at least eyes and jaw.... Also, leave the 3 piece rod at home and get a readi-rod. However, on a more positive note, your guns do sound like beauts, how about posting some pics so we can all covet? for every hour in front of the computer you should have 3 hours outside | |||
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AIU; I just started working with Retumbo but haven't found a load I am happy with yet. I don't push my loads right to the limit so I still expect to be in the same velocity range. My rifle was built by Rocky Mountian Rifles and when I had it built I was more interested in accuracy than building the hottest loads on the range. If I can get 3200fps with a 200 grain Accubond while retaining a sub-inch group I'll be happy.  | |||
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Mark, I'm not concerned about life-and-limb - there's no credible evidence that I'm even close to blowing the gun up. The loads I've listed are a tad hot, but well within the constraints of the brass case - at less than half the operating limits of the bolt-action guns. Even at 75,000 psi you're working at no more than half the up limit for bolt-action guns (i.e., >150,000 psi - read the article I posted above). It doesn't take a rocket scientist to realize that the brass case is the limiting factor in load development - brass is much, much, much softer than chrome moly or stainless steel. If you don't believe it, take a hammer to a brass case and, then, to your gun steel barrel. After a few swats, your brass case will be "road kill", but your barrel probably doesn't even show a scratch. The "recommendations" put out by the various reloading manuals and SAAMI are deliberately very conservative to cover the many sub-standard guns and reloading components out there. Moreover, with reloading manuals Nosler, Hornady, Speer, etc. are SELLING INFORMATON, which is a product; and, they are liable for that PRODUCT. If someone blows themselves up with any recommended load from their reloading manual, they can be successfully sued - hence, they must be very conservative to minimize their risk. A Speer ballistics engineer flat-out told me product liability issues are very important for all their products - including their reloading manual. I don't blame them. In fact, I personally wouldn't get into the business of reloading manuals. Indeed, I bet these companies wouldn't have reloading manuals, if they weren't necessary to promote their products. The effect of all this is that people (like gun control nuts) have been whipped into a paranoid frenzy - "if I reload over SAAMI I'll blow myself up!" This may be true, if you're shooting an old junker; but, it's not true if you are shooting 1) first-rate, modern bolt action rifles that have been well maintained, 2) reloading carefully & knowledgeably with first-rate modern components, 3) using the slowest burning powder that will produce the desired pressure, 4) tracking your results with a chronograph and the NECO internal ballistics program, and 5)shooting "hot" loads as infrequently as possible. Moreover, you have no other choice than to stay within the limitations of the brass case - that is, if you want to reload that case a second time. Moreover, the latter should be one of the criteria - the spent cases from the "hot" rounds must be reloadable. My main concern is getting a stuck case, when you need that critical second shot - indeed, a good reason not to get too hot with hunting loads. | |||
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Alf, what was the load you froze that SAKO action with? I've blown primers with no damage to the gun - just some leaking gases. I always wear eye protection (as well all should) for this possibility. I have always found premonitory evidence that pressures were rising to the 65,000 to 75,000 psi levels. They are: 1) Loose primer pockets - usually only after a few loadings. I hand prime (feel) the primers into the pockets - it's easy to tell when they are getting loose. I believe this is the most reliable early indicator. Indeed, one can consider the brass case a type of copper crusher ("BUP" not CUP). Brass will "crush" (like copper) and indicate pressure. 2) Extraction marks, especially with the R700 action. For Mauser and Mauser-like actions (M70 or Sako) extraction marks are less reliable. 3) Sticky bolt lift - but, only in totally resized cases. If you neck size only, the cases will get tighter and tighter, eventually forcing you to resize - no matter what pressure you're shooting. It just happens sooner at high pressure. 4) Finally, a black ring around the primer or a blown primer at ~75 to 80,OOO psi. - but only in a new case. A case with a loose pocket already will blow at lower pressure. | |||
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I've blown primers with no damage to the gun - just some leaking gases. I always wear eye protection (as well all should) for this possibility. AIU- I'll respectfully disagree with that statement, if a primer blows there is ALWAYS accompanying wear to the gun, you just aren't seeing it! Fortune Cookie says "Steel Rain In Your Future" for every hour in front of the computer you should have 3 hours outside | |||
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Mark, with every round fired there is some additive wear to the gun, although miniscule. Some wear occurs even with low-pressure loads. Likewise a round producing a blown primer will cause some wear to the gun, but it's not as catastrophic as many might think. I agree with you that the wear caused by a blown primer is greater than without - but, still quite small in my experience. I avoid blown primers, and in my shooting, blown primers are rare events - occurring only when I'm experimenting with a new load and/or bullet, especially with a relatively fast-burning powder. The loads I've listed here have never produced a blown primer for me - in fact, the cases are reloadable. I don't shoot hot very often, only before big game season to sight the gun in and harvest the game. | |||
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Do you think the game you shoot will notice the additional shock? It seems that you're loading to the maximum just for the sake of doing so. Are you considering the temperature at which your primers blow? Manual max loads are conservative because they tend to allow the gun to stay together even in hot weather. | |||
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Yup. Figure roughly an additional 200 PSI per degree F of chamber temperature. Prove all things; hold fast to that which is good. | |||
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Ralph, I've never toasted a primer with R19. With the 3006 AI/165 NBT/R19 combo, I've been up to 68 grs. but I thought it was too hot and backed off to 66 grs., which has never given me any trouble at any temp. I think I've got a slow lot of R19 - it acts more like R22 or MRP, but faster than R25. I really don't think I'm much above 65,000 psi. | |||
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Burn-rate chart from Hodgdons Powder Co. 90. W-760, Winchester 91. H-414, Hodgdon 92. N160, Vihtavuori 93. IMR-4350, IMR 94. H-4350, Hodgdon 95. N-204, Norma 96. Reloader 19, Alliant 97. IMR-4831, IMR 98. XMR-3100, Accurate 99. H-450, Hodgdon 100. H-4831, Hodgdon 101. MRP, Norma 102. N165, Vihtavuori 103. Reloader 22, Alliant 104. IMR-7828, IMR 105. H-1000, Hodgdon 106. XMR-8700, Accurate 107. H-870, Hodgdon Note that Re19 is amoung the slowest 10% of available powders. I shouldn't be surprised that a "slow" lot is behaving more like MRP or Re22. I going to KEEP my remaining Re19!! I think I've got a great lot. | |||
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What wear in particular are YOU referring to here? The wear I am referring to is not a "greater" wear, but a totally "different" wear. Post a picture of either bolt face you have and I'll show you what I mean, if you've blown primers like you say you have it will be obvious. for every hour in front of the computer you should have 3 hours outside | |||
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This thread almost tells me a lot of you guys have had a long winter. You need to get out and do some varmint shooting, or target shooting, instead of sitting at the computer and pondering academic questions like this, that none of us have the facilities to test for any results. So it is all just theory to each of us, until it is actually tested. Then at the same time, if you buy a new car, and the tachometer on it goes to 10000 RPMs, do you sit in your drive way and rev the engine to see if anything will happen to it, if given 10000 RPMS for 5 minutes???? Some guys criticize me for searching for the limits of my firearms, to see what I feel is the border of a safe load and an unsafe mode, telling me that SAAMI already tells us that answer. But then we have guys who want to explode something or see how far it is to get to that point........ I just hope spring gets here soon for some of you guys. You must be driving the wife nuts! cheers seafire | |||
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Alf, you're saying that gun blew-up at 60,000 psi - EVERYONE POSTING ON THIS BOARD SHOOTS AT 60,000 PSI! The loading manuals are full of loads at 60,000 psi and beyond - up to 64,000 psi and higher. Moreover, why didn't the bullet move? - you say it hardly moved. Was there obstruction? I agree an obstructed gun will blow up - I witness a mild mannered 308 blow-up next to me, after the the shooter left a cleaning brush in the barrel. Please explain your pictures. A blown primer will not do what you're showing. Mark, the bolt face of all my guns look brand new - trust me. Besides the guns have been rebarreled for different calibers and the gunsmith, who is very competent, made no note of the bolt faces on any of the guns. | |||
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I once read someplace (don't remember where and don't care) about an experience the writer observed with a large-bore revolver (it was a .45ACP or .455 Webley or something similar) that had been routinely fired by its owner or custodian with heavy handloads that exceeded what everything in print said was safe. However, the shooter was sure that everybody else was wrong, because he couldn't see any damage to the gun. One day he dropped it, I think on a bathroom floor, and it shattered into pieces. A word to the wise is sufficient. | |||
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I have stayed out of this thread because even though I have loaded rifle ammo for 30+ years I seem to know less and less about the subject. For sake of information and not to be argumentive, I would like to ask a few questions of the members. 1)With modern firearms and modern new brass, is there any reason one can not load to 65,000 or 60,000 psi. even though the saami spec is much lower? 2)How does one apply the use of new powders. Just because a particular powder hasn't been used in a specific case doesn't mean it couldn't. How will you know where to go and when to stop. 3)Are all of the algorithms in Quick load accurate? 4)As a hunter, I am concerned less and less about how many reloads I can get out of a case. I also know that, likely as not, my hunting rifle will out last my longevity and a life of 2-5K rounds is plenty for me. I know of a 30-378 that had the barrel shot out in less than 250 rounds of factory ammo. A 7 STW that went bad after 200 rounds of factory ammo. Did they fail or is it within the expected life of the product. Remember a grenade has the life expectancy of ONCE by design! 5)As a custom rifle user and a collector, I want to get optimum ballistics from my rifles without overt harm. 6)Some of my rifles are for exotic or hard to find cases and I do on these want to conserve them. On these I would accept less than optimal ballistics. 7)If the brass case is the weakest link, at what average pressure will normal new modern brass fail? 8)will primer pockets get loose with low powered loads just from the constant resizing, de capping, and re priming? I have loaded in excess of 200,000 rounds in my career and have had a failure twice. Both on the same rifle with brass that was weakened from too many firings (case head separation). I checked the brass and separated the ones with weak primer pockets or web thinning. That group of culled brass was inadvertently added back to the good group and reloaded again. A failure resulted. I disassembled all rounds, 200 of them, and started over. I must have overlooked one and did it again. All for the sake of economy on an AI 257 Roberts. The load itself was warm but not overly hot as I was able to get at least 10 loadings before things got loose. Finally, is there a tool one can use to check if primer pockets are loose instead of priming a case and then punching out the loose primer? square shooter | |||
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Alf, that gun had to be obstructed - otherwise why didn't the bullet move. If that action "moved" before the bullet at 60,000 then we're all in serious danger. By the way, there's a load for the 3006 AI (180 gr) in the Nosler manual that must be 65,000 psi plus - at least according the NECO. Read the article below - these people make guns - not just posts on a reloading forum.
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LB, You can't just assume that modern brass is stronger just because it is new. We have not yet genetically engineered superbrass that can withstand the abuse proposed by AI. We have the same brass as before, however the newer cartriges that are designed to operate at 65K PSI have thicker and therefore stronger caseheads. You can't load a 22-250 to 65K PSI without risking failure. But you can load a 223 WSM to that level safely. Different casehead designs. I'm sure that a new generation of high pressure rounds could be developed, that by design would operate at 100K PSI. This would require much thicker brass, probably so much so that the gun would have to be unreasonably bulky. Or maybe we could dispense with brass alltogether and go with a caseless design. But then AI would be posting another proposal where he would be pushing the tensile strength of the steel, and arguing why he feels its OK to load to 149000 PSI. Still, watching an Elk disintegrate like a prairie dog after AI's 165 grain bullet hits it at 7500 FPS would be worth it, in my opinion  | |||
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At long last, I have a short answer to AIU's original question: Excessive pressure is the pressure that, when it's too late, you wish you had not achieved. Prove all things; hold fast to that which is good. | |||
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Ralph I appreciate the information. The 222 loaded by norma was loaded to much highter pressures as indicated by speed. My load book puts that round chronographed at 3312 f/s with a 50 gr. bullet. You may be right mostly, but I have sectioned brass for the 257 Roberts made by Federal, Winchester, Norma, Remington and a few others. The amazing thing is the inconsistancy in the internal case size read brass thikness. The worst brass I ever used to produce AI 257 Roberts was the Remington. It had thicker brass but the brass was brittle and fireform loads that converted other brass to AI just split the necks on 3 out of 5 rounds. Pitiful. There does not seem to be an easy and conclusive technique described. square shooter | |||
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I believe some posters here are over reacting - operating at 65,000 is not dangerous in modern bolt-action rifles. Alf shouldn't be posting a blow-up that was obviously secondary to chamber/bore obstruction - its disingenuous. If the bullet hardly moved, there was obstruction and the gases had no place to go but backwards. | |||
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heh denton++ | |||
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