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Thread: Myths and BS in reloading "wisdom"

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    Default Myths and BS in reloading "wisdom"

    We've been exploring the use of gas checks on cast bullets in another thread and questioned the conventinal wisdom that gas checks protect the base of lead bullets from being melted by the hot gases. Evidence to the contrary includes the fact that the bases of paper patched bullets don't even get discolored by the heat of full charges of smokeless powder.

    Any one else have any knowledge to share disputing "convientional" wisdom in reloading they can share?

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    My favorite (or is it least favorite?) BS and myth about reloading is all the high pressure loads floating around on the internet. There's probably a thousand for every one that's actually been pressure tested. Just cuzz it didn't blow up or damage a gun right away, doesn't mean there is no long term wear and tear. The 45-70 has spawned the most, but the 44 mag isn't far behind. I've seen three Marlin 1895s and guide guns now that had their receivers ringed by excess pressure. To the point that scope mounts won't fit flush against them. And the owners weren't even aware of it till they decided to try mounting scopes. Makes me really wonder how many more are out there undiagnosed.

    I figure my guns are a lifetime investment, and any load that cuts down on that life is too hot. Therefore I only shoot loads that have been pressure tested, and I work up to them from below using the best methods I can manage to watch for excess pressures that show up before I reach "book" max. And I listen to what the gun manufacturers say is max for their own guns. I figure if anyone knows what they're talking about it would be them.

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    Default Bases of bullets melting

    As I mentioned on the paper patched bullets I don't have any actual experience - I can only go by the polific posting on the web that the patches don't get burnt or damaged. I've been reading about this for decades but never got around to trying it myself as I noted. I'll send you a bunch of links and references if you like but they aren't hard to find.

    I do know that I've shot a lot of loads myself with various fillers like Kapok and cardboard wads over the powder and found these intact in front of the bench. The lack of damage to overpowder wads is well known and documented - these little pieces of cardboard end up between the base of the bullet as it goes down the barrel. If I can get down to the range this weekend I send you some. Like FMJ bullets they usually show the impact of the powder grains impacting but no scorching or burning. I can verify from personal experience that this is true.

    I can also show you plastic overpowder wads from the shotgun range that aren't melted. I'm sure I can dig out some FMJ bullets with an exposed lead base that aren't melted - you proably have some yourself - take a look at them - there are no signs of melting at all.

    I never stated that gas checks do not work - I did state that in some cases they are not needed and advised Brian to try it and see what happens. At worse he may get some leading but he isn't going to damage the gun with a few cylinder fulls of bullets without gas checks. In many cases he may have to use an extra patch or two but big deal. I have shot many rounds of cast bullets with and without gas checks and for some loads found no noticeable difference in accuracy or leading - my recommendation is based on real lfe observation not specuation.

    As I stated in a previous post the statment of "we aren't certain exactly how gas checks work" has been around for probably a century or so. Is there something you know that no else has knowledge of? As I also stated - I'll never stop learning and I'm always open to new ideas and real knowledge - not just old myths repeated.
    Last edited by Murphy; 03-09-2008 at 16:12.

  4. #4

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    Given an anoxic environment it is entirely feasible for a wad to not be charred. Nitro based powders are very clean burning under pressure. Although I would agree that some wads pictures would be nice. I doubt that the account was fabricated.

    How hard are you shooting the bullets? A proper alloy for any given pressure will yield a clean shooting bullet. Gas checks allow reloaders to be a little sloppy in proper load combinations. The loader may shoot an alloy out of it's "comfort zone" relying instead on the gas check to seal the bore. Plucking gas checks off of bullets stacks the cards in favor of your argument. The new pseudo bevel-based bullets wouldn't obturate as effectively as a flatbased bullet and wouldn't seal the bore as well as the gaschecked bullets would.

    A fair comparison would be similar designed bullets, one with a gas check and one without shooting the same alloy at the proper pressure with proper lube for the given application.

    Yes, gas checks make life easier. But they are not a magic cure-all for leading. You can shoot non-checked bullets at high pressure and not get fowling.
    Last edited by Murphy; 03-09-2008 at 16:13.

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    Default Theories on GCs, patches, etc.

    I think the "melted lead bullet base" theory goes way back to guessing about wild fliers as the pressures or charges went up during load testing. Seemed logical that extremely hot powder gas behind a lead bullet would melt the base and seriously affect accuracy. The theory still hangs on I guess. From what I understand about it.... yes the burning powder gas behind the bullet is very hot BUT two things....1) the time the hot gas has to work on the base is very, very short, 2) the specific heat of the gas plasma is relatively low.

    So the current and pretty well accepted thoughts about it are.... the gas escapes by the base or by one spot on the circumference of the base and erodes or cuts up the sides of the bullet. The eroded particles of lead are then deposited along the bore surface and accounts for much of the dreaded "leading". This condition would likely lead to basic bullet inaccuracy. And for sure cause cumulative accuracy problems as the lead deposits build after each shot. If the base has enough strength and maintains its integrity during the bullet flight down the bore and successfully seals the gas behind.... it's still no assurance of an accurate bullet exiting the muzzle. The structural integrity of the bullet may be upset where the whole bullet obturates unevenly or slumps unevenly. This leaves the base of the bullet not plumb with the muzzle crown as it exits and/or the bullet wobbling around it's axis during its flight to target.

    A gas check can help mitigate the conditions in the former example where the gas escapes from around the base but has little to do with the latter condition. That has to do with the shape and peak of the pressure curve as it relates to the acceleration of the bullet versus the hardness, design, diameter, mass of the bullet.

    Patches are a different story. Thick, tightly woven cotton patches can easily withstand large charges of black powder burning behind them when wrapped around a soft easily obturated round ball in a muzzleloader. A correctly fitted, patched round ball is very accurate and the patch is almost always found wholly intact after firing... with little evidence of burning.

    The paper patch is yet different. The thin cotton paper wrapped around a soft, pure lead, smooth-sided bullet usually comes out the muzzle as confetti. The confetti is not burned but just heavily scored by the rifling as it's sandwiched between the obturated bullet and bore during the ride down the barrel then shredded by the muzzle blast as it leaves the muzzle. Some swear they recover whole paper patches after firing but that may be the result of either very low pressure loads or undersized bullets that don't obturate fully to groove diameter or bullets that are too hard to obturate fully, etc. Those are the paper patches most likely to show charring.

    Just some thoughts and observations.

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    I'll have to disagree with you there, Murphy. It's not wisdom, it's objective science. Wisdom is defined as having a knowledge of what is right and the ability to decide what to do as a result. Objective science is about hypothesis, testing hypothesis to come up with a theory, repeatability, and continuing to iterate towards fact. You had the wisdom to decide that only objective science held the path to success. (Gawd I'm weird!) I think the paper wad and gas check experiments would be fun however and I am an engineer. I wish our politicians were as weird as me ...maybe we'd get somewhere for a change ...or for a lack of change (best country in the world and they want to CHANGE it? Go figure...)

    Oh, I never passed my PE ...never tried passing it. I did pass my EIT though, which is a prerequisite ...and later developed enough wisdom to realize getting a PE license was a route towards contract work ...long hours short schedules, no time for fun and family. Been there and done that! No more 80-100+ hour weeks for me! I prefer the steady day job route. No contract career for me!

    Brian
    Last edited by Murphy; 03-09-2008 at 16:14.

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    Default exposed lead bullet base

    Ever since using the partition bullet in all manner of high pressure, high velocity, large charge volume cartridges I have wondered why the only damage to the exposed lead base of such bullets examined after firing and recovery were the random cratered impressions of powder kernals. Yet when searching for the reasons for errant bullet flight from relatively mild loads with cast plain base bullets (maybe 1/3 the pressure and 1/3 the quantity of powder charge) where the bullets are roughly the same alloy/BHN as the partition core... the gas cutting damage to the base edges and sides of the offending recovered bullets is obvious.

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    Default Absolutely! mostly

    Having put a few plain based and gas checked slugs down the bores of both revolvers and rifles myself, there is little doubt in my mind also that leading is reduced, sometimes significantly, by using gas checks. I've also come to the conclusion that in most cases accuracy is enhanced by the use of gas checks or at least accuracy is easier to attain with their use.

    Exactly when, where or how that lead is stripped from the bullet may be up for debate but there is no doubt that it does and it can be a pain

    Kind of a sidebar to the gas check discussion.... during experimentation with various gas checked handgun loads.... particularly in revolvers.... I've left more than a couple in the bore. I've even left a few half jackets in the bore. It pays to heed the warnings about the minimum velocities for gas checked bullets listed in some load manuals. [It's really not a direct issue of velocity but more of the minimum residual pressure needed to keep the gas check on the bullet in light loads..... particularly problematic in revolvers after the bullet passes the cylinder gap] Probably not a good idea to shoot a bullet back over a stuck gas check

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    Default Gas checks, gas errosion, lead melting, etc.

    At least we cleared up that gas checks aren't absolutely needed all the time!

    For the record - gas errosion / cutting often takes place at temperatures far below the melting point of the metal. I've worked with high pressure gas and steam valve seats that looked like they had been cut with a torch yet the temperatures involved were thousands of degrees below the melting point of the metal. Melting snd gas cutting aren't necessarily the same.

    Has anyone ever examined the "leading" around a revolver cylinder gap and postively determined that the metal was actually melted rather than sprayed at such a high pressure that the small lead particles splattered? I don't know - I'm just asking. I've never been afraid to admit I don't know everything about anything including cast bullets. I do have a large assortment of questions with answers I'LL PROBABLY NEVER KNOW.

    I think I owe Murphy some overshot wads and undamaged paper patches.

    Murphy does owe me a public apology for stating he didn't see how I passed the PE Exam. That statement was totally unjustified, unethical, and very unprofessional from an engineer and a moderator. I'm frankly very disappointed that I have not received an appology by now.

    Also what is the 'frogs iwhout legs" comment about. I can only hope this isn't an insult!
    Last edited by Murphy; 03-09-2008 at 16:15.

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    Murphy:

    I like that one.

    I figger a lotta Science is like that.

    Smitty of the North
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    It ain't the base that melts. Proof is in recovered bullets. The gas check does keep gas from flowing beyond the base. High pressure loads in rifle using tube jacketed bullets bullets removes any doubt. Lead is exposed at the base. Recovered bullet show no sign of melting at the base.

    Least we forget!

    Any doubts? Remember the old Noslers when they used tube jackets?

    In heavy loads such a the .300 Wby with the old Noslers do you ever recall any discussion of this problems. I can remember more than just a few people asking me why doesn't the lead in the hole at the base melt?

    The answer in this case is the insulation provided by the thick jacket.
    "The tree of liberty must be refreshed from time to time with the blood of patriots and tryants." (Thomas Jefferson

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    Quote Originally Posted by Big Al View Post
    It ain't the base that melts. Proof is in recovered bullets. The gas check does keep gas from flowing beyond the base. High pressure loads in rifle using tube jacketed bullets bullets removes any doubt. Lead is exposed at the base. Recovered bullet show no sign of melting at the base.

    Least we forget!

    Any doubts? Remember the old Noslers when they used tube jackets?

    In heavy loads such a the .300 Wby with the old Noslers do you ever recall any discussion of this problems. I can remember more than just a few people asking me why doesn't the lead in the hole at the base melt?

    The answer in this case is the insulation provided by the thick jacket.
    Copper isn't an insulator, it's a conductor. It will transmit the heat right into the lead. If you don't believe me grab a copper wire and hold it in a flame as long as you feel comfortable. The base isn't melting despite the copper transmitting all the heat.

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    Quote Originally Posted by tvfinak View Post
    We've been exploring the use of gas checks on cast bullets in another thread and questioned the conventinal wisdom that gas checks protect the base of lead bullets from being melted by the hot gases. Evidence to the contrary includes the fact that the bases of paper patched bullets don't even get discolored by the heat of full charges of smokeless powder.

    Any one else have any knowledge to share disputing "convientional" wisdom in reloading they can share?
    Lemme think about this......
    Powder charge is maybe the most important factor in accuracy with cast bullets in rifles. When my load is not accurate, I reduce the powder charge until it is, or try another powder. The theory is that the correct powder charge, results in less damage to the bullet, and that's why the better accuracy. Although I am relying on the experience/writings of others more than my own, this would be a plausible explanation.

    Is there any doubt that a Gas Check can protect the bullet's base from damage?

    Leading, is sort of welded onto the barrel, and not just deposited loosely, like a powder or dust. In other words something heated it up and melted it. Friction doesn't have to be the only culprit here.

    While, I wouldn't discount the other factors, if a gas check can better seal the edges of the bullet it can help prevent leading, and can make the powder charge and/or type less critical.

    Is there any doubt that the blow-by gases, around the edges of the base of the bullet, can cause the lead to be melted onto the barrel? Not in my mind.

    You can choose to solve a leading problem in a number of ways, dimensions, lube, alloy, charge etc. and have success, but using a Gas Check seems more like a Good option, than an Unnecessary one.

    I arrest my case, or am arrested in case, or in case I get arrested, IÖ Whatever, I donít wanna think about that.

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    Quote Originally Posted by BrownBear View Post
    My favorite (or is it least favorite?) BS and myth about reloading is all the high pressure loads floating around on the internet. There's probably a thousand for every one that's actually been pressure tested. Just cuzz it didn't blow up or damage a gun right away, doesn't mean there is no long term wear and tear. The 45-70 has spawned the most, but the 44 mag isn't far behind. I've seen three Marlin 1895s and guide guns now that had their receivers ringed by excess pressure. To the point that scope mounts won't fit flush against them. And the owners weren't even aware of it till they decided to try mounting scopes. Makes me really wonder how many more are out there undiagnosed.

    I figure my guns are a lifetime investment, and any load that cuts down on that life is too hot. Therefore I only shoot loads that have been pressure tested, and I work up to them from below using the best methods I can manage to watch for excess pressures that show up before I reach "book" max. And I listen to what the gun manufacturers say is max for their own guns. I figure if anyone knows what they're talking about it would be them.
    BrownBear:
    It's that bad, huhn?

    I think maybe, that stuff is a result of another "myth". The one that says, loading manual data is always on the low side, because the publishers don't wanna be sued, and you can always greatly exceed it.

    Like that Gun Writer, who gets 3000 fps with a 180 grain bullet in his 26 inch barrel 30-06, WITHOUT PRESSURE SIGNS, and he knows the load is safe in his gun. Like as if, 3000 fps itself, isn't a pressure sign.

    Handloading is too hazardous to be too adventurous.

    Smitty of the North
    Walk Slow, and Drink a Lotta Water.
    Has it ever occurred to you, that Nothing ever occurs to God? Adrien Rodgers.
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    Default More hot gas theories

    I used the example of paper patched bullets as an example of bullets not being damaged by the hot gases or blow-by. Remember this is a just good grade of plain old paper!

    I'll give another example to the lack of hot gas damage many of us are familiar with - the plastic saboted Remington Accerator ammo. Here we have plain old plastic at some pretty respectiable velocites and pressures that doesn't melt or gas cut - and there were no gas checks on these. There are other examples of plastic saboted rounds but the Remington are probably the most common to most of us.

    So here we have fragile paper and plastic covered bullets that don't melt or gas cut - yet tougher harder cast bullets somehow have a problem.

    We also know that lubrication of cast bullets is critical for both accuracy and to avoid or minimize leading. Anyone that has ever shot an unlubricated bullet at any velocity knows what happens!

    I had remarked before how high pressure gases and steam are well know for cutting though very hard metal with melting points thousands of degrees above the temperatures of the steam or gas- no melting at all.

    Putting these thoughts together let me toss out a theory out to consider -starting first with rifles:

    The initial damage and leading to the cast bullet is done by friction and heat resulting from a lubrication failure. Some metallugical properties of the bullet metal may factor in here - we aren't certain - all we know is the hardness. This damage and resulting leading is similar to what is seen when a bearing get "wiped" in an engine if you lose oil pressure. It's also interesting to note that babbit or bearing metal used in these bearings is not very hard - there must be a reason - I'll do some more research or perhaps some can tell us why babbit metal is used.

    After the bearing surface of the bullet is damaged THEN we can get blow-by and errosion. We may get additional leading but the real mess is the streak down the barrel where we left the surface of the bullet after the lube failure.

    Gas checks can possibly enter into the situation in a couple of ways - not just protecting the base of the bullet from "hot" gases. One of the functions a gas may do is act as a scraper to scrap the lead deposits left in fron to it off the bore surface. I used to load cases up with a stack bare gas checks on top of a charge of Bullseye to help remove the leading in my .357.

    A second and more critical function of a bore sized gas check - i.e. Hornady - is to maintain the seal and prevent gas from leaking by and further cutting the damaged side of the bullet. My guess is that the spray of erroded material from the gas cutting- since it is traveling parallel to the bore - would result in very little leading. Remember that a bunch of lead has already been melted from the bullet and left back toward the breech before the errosion begins. This is the bult of the leading we see.

    I suspect that in the case of revolvers a number of things contribute to the lubrication failure. In a lot of revolver with cylinder throats that are too large - or the bullets too small - gas blow by could start in the oversized cylinder. The pressure is still not too high but the gas could easily remove the lube off the bullets and possibly even start some errosion. When this bare - at least on the surface - lead bullet hits the forcing cone and throad you get your leading. One the bullet bites into the bore and rifling more lube is displaced and the leading is lessen on down the bore.

    If the errosion of the bullet in the chamber was significant the gas check will maintain the seal integrity and may also act as a scraper - just like in the rifle.

    Looking back at the paper patch bullets and saboted rounds again we can see how these are sucessfull. Hot gas and melting is not an issue and we don't expereince damage to the projectials like the lubrication failures we get with lead. Do recall that plastic materials are generally decent bearings and the paper patches are lubricated with some sort of wax or grease.

    I'm open for feedback to support or destroy.

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    And don't ever forget that the lead tip of a jacketed bullet melts once velocity reaches 2600 FPS or more. :-)

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    Default Gas Checks etc.

    When you look at the situation, the gas check is really primarily protecting the bearing surfaces of the bullet - not the base. I have yet to see the base of a cast bullet that was damaged by shooting. Don't really matter I guess but just to be correct.

    Any gas blowby will be spraying the particles a head parallel to the bore with the bullet following right behind to either wipe them away or iron them inot the bore. I don't think much would stick but who knows.

    My position was that gas checks aren't always needed on light and medium loads. For heavy loads they are almost always desireable. As far as I can reall the high accuracy shooting with cast bullets has been with plain base bullets so i can guess in some cases they aren't desireable.


    Is there any doubt that the blow-by gases, around the edges of the base of the bullet, can cause the lead to be melted onto the barrel? Not in my mind.

    but using a Gas Check seems more like a Good option, than an Unnecessary one.

    I arrest my case, or am arrested in case, or in case I get arrested, I… Whatever, I don’t wanna think about that.

    Smitty of the North[/quote]
    Last edited by Murphy; 03-09-2008 at 16:20.

  18. #18

    Default babbit bearings

    Couldn't help but chime in here a bit. One reason that bearing caps such as those on main bearings on crankshafts in engines are relatively soft is so that any hard particles that get ingested into the engine oil reserves will be pressed into the bearings rather then staying stuck between bearing and crank journal, causing more damage to the crank. A softer bearing would also cause less damage on its own to a crank journal then a hard one, and considering that in a properly functioning engine there is a good pressurized cushion of oil, a bearing being on the soft side was no problem. Also, on early engines, the babbit bearings were sometimes poured into place, so an alloy was needed that would melt easily.

  19. #19

    Default to gas check or not to gas check

    Reading this thread, there seems to be a hostile note from the beginning which I don't fathom. At any rate, what I know from personal experience is that the higher the velocity in either a handgun cartridge or in a rifle cartridge, the more need for a harder bullet alloy. If this is for target use only, then even pure linotype wpuld work. But, my own experience showed me that hard bullets were often not as accurate. As i looked into this phenomenoa, I found out about obturation and it's importance in getting better accuracy. So, for that reason mainly, I started casting and using gas-checked bullets. Even with a really hard alloy, it helped create a better level of accuracy. I also found out that the leading from softer bullets being moved faster then the norm was greatly reduced. As time rolled on, I was able to formulate alloys that were a good balance between hardness and obturation, with or without gaschecks.

    I also tried paper patching bullets cast to be so prepared, but it was really a p.i.t.a. so I gave it up. I was able to devise accurate loads without the hassle.
    But, and this is my main point, I found out that gaschecked bullets on various hardness' of alloy did indeed reduce leading, but that shooting plain base bullets below a certain velocity didn't lead much IF the loads were light enough. Heavier loads, leading. But hey, that's why I have Lewis Lead Removers for 3 different calibers.
    So, I don't really give a hoot about any scientific explanations about the subject, only that I know what happens from actual experience and after all, isn't that what counts? To me, intellectual wisdom is often less valuable then bench smarts or street smarts if you will.
    This isn't an opinion, this is an observation from my own experience.

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    Default Obturation and bore sealing, leading, etc.

    Obtuaration of the bullets to seal the bore seems to be a popular explaination for the reduction of leading. I'm not certain if I totally understand what is though to happen so can somone help me out here by answering a few questions?

    -Since the cast bullet is most likely seveal thousands over bore size why does it need to obturate to seal? I know some old hollow based bullets were made to expand and seal the bore but we are talking about solid based bullets with or without gas checks. If the bullet has a gas check it shouldn't it continue to seal regardless even if the bearing surface is damaged.

    -How does the bullet deform or obturate to effect the sealing? Does the rear section flare out or the whole bullet get shorter and fatter or ??

    -Can anyone provide an example of a recovered bullet that obturated noticeably?

    I've got an open mind - help me our here.

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