JimGnitecki
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- Mar 28, 2010
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Lyman's latest online instructions say NOT to leave a bullet casting inside the mould as a corrosion preventative. They say it does not provide corrosion protection long term.
Jim G
Jim G
I don't cast but shoot BPCR with lots of folks with Pedersolis and Shilohs. If you size your 500gr bullets at .460, then your hardness level is not much of an issue. It can be on the soft end or the hard end of BHN. However, I will say they prefer 16-1 alloy.
OK I'll play, what does bullet yielding mean and what is the pressure for proper opteration of the base of your bullet. I further question using a crib sheet used for lubed bare lead with powder coated bullets. One person called it a soft jacket, I'm keen on that being a fairly accurate assessment.Hmm. The expression "16 to 1" generally is taken to mean 16 parts Lead and 1 part Tin, or about 94% Lead and about 6% Tin. No antimony. Such an alloy apparently has a hardness of BHN = 11. Per the Lee Hardness Tester crib sheet supplied with the Lee tool, BHN 11 can handle only 15,700 psi. Lee recommends that you keep the peak pressure of your handload to 10% under the maximum psi the alloy can handle with yielding, so the peak pressure for a BHN 11 alloy is then about 14,100 psi.
But I am using Accurate 5744 powder. The load tables I have found for that powder with a 500g lead cast bullet call for minimum loads of 20.2g producing as much as15,900 psi (per Hodgdon's load table for Accurate 5744).
For a 15,900 peak psi load, Lee recommends a BHN of about 12.5. Hence my target BHN of 12.5.
For higher velocity 500g loads, still with Trapdoor level peak pressures no higher than about 18,800 psi, the Lee crib sheet suggests a BHN in the high 14s, close to BHN 15, which is pretty much Lyman Alloy No. 2, which consists of 5% Tin, 5% Antimony, and 90% Lead. The Antimony is what spikes the hardness in Lyman Alloy No. 2.
Most recerational shooters probably settle for the Lyman Alloy No.2 because even Lyman itself says this will work reasonably well in most shooting (i.e. for shooters in the central part of the bell curve not looking for either notably softer for low pressure loads or notably harder for high pressure loads). But, shooters shooting high pressure Magnums, etc are going to go higher on BHN to avoid any possibility of leading, while shooters shooting 1800s type rifles and handguns are going to go lower on BHN to ensure bullet obturation, especially in barrels on the high side of barrel diameter, to get better accuracy.
In fact, many shooters of "buffalo rifles", especially the Pedersoli models, suggest an alloy that is JUST hard enough to not lead the barrel, and up to .002" larger in diameter than the groove depth in the rifling of the barrel. The soft alloy helps the bullet to obturate easier for a snug accurate fit. Since I am going to the trouble of casting my own bullets, and want to try shooting the Pedersoli at up to 600 yards (the max range distance at my home range), THAT is what I am intending to go for!
Jim G
OK I'll play, what does bullet yielding mean and what is the pressure for proper opteration of the base of your bullet. I further question using a crib sheet used for lubed bare lead with powder coated bullets. One person called it a soft jacket, I'm keen on that being a fairly accurate assessment.
My point being yield is a scientific term not related in any way to gas cutting, and deformation caused by the lead yealding is what causes opteration. This is a desired trait. The powder coat prevents gas cutting, because it has a much higher vaporization temperature, and this prevents the base melting and leaving lead deposits. I agree that Lyman and Lee do not cover PC because they don't sell it, and it replaces profitable products in their lineup. As an additional observation I would never under any circumstances use a wood dowel in any barrel. Aluminum, brass, bronze, copper are all much better alternatives.Basically, Lee says that if your load potentially develops a peak pressure high enough to hit the yield point of the alloy you used to cast the bullet, the metal "yields" and can no longer prevent blow-by and leading. So, Lee recommends you stay about 10% below the yield pressure, where you suppsoedly get good obturation without the risk of leading.
As for how a (good) powder coating behaves under pressure: The various attempted destructive processes tried by shooters who powder coat suggest that the powder coating is NOT hard or brittle. Rather it is a polymer that binds aggressively on a molecular level to both itself and the metal it has been applied onto, and it remains FLEXIBLE. Even on bullets that have been pounded down almost flat with a hammer, the powder coating on the resulting "blob" is STILL UNfractured.
You cannot treat a powder coated bullet the same as a metal jacketed bullet. The level of friction between the jacketed bullet and the polymer powder coated bullet are on two different planets. A jacketed bullet stuck in a barrel has to be pushed out via a hammer hitting repeatedly, hard, on a metal rod. A low-BHN cast lead bullet can apparently be pushed out with a WOODEN dowel.
And, you can apparently SIZE a powder coated bullet in a regular sizing setup (like the Lee sizer) without fracturing or scraping off the powder coating. This apparently makes it possible to coat a bullet that casts as , for example, .459" diameter, powder coat it (adding maybe .002" or more to the diameter), and then size it down to either .459" or .460", without disturbing the coating!
So, in essence, a good powder coat is more like a flexible but VERY durable "sleeve" within which the bullet shape can actually be altered without destroying the integrity of the coating, which continues to prevent blowby and the resulting leading of the barrel. And, it does not build up in your seating die (and on everything else it touches).
One obvious attraction is that if your load's BHN is borderline or worse in terms of resistance to leading, the powder coating appears to be far more robust than a typical bullet lubricant. That gives a reloader more flexibility and more room for error on the BHN.
Yes, this does all sound "too good to be true", but since shooters all over The World (it started in Australia) have been doing it for over a decade, I guess it is considered "proven", so I intend to try it myself.
Notice that the traditional makers and suppliers of bullet lubricants and the tools used to apply them don't talk about powder coating. That's NOT because they can cite any problems with it (unless someone uses an inappropriate or low quality powder). It's because they don't SELL powders or powder tools and equipment, so even mentioning powder would potentially divert prospectives buyers away from their offerings.
Anyway, within a few weeks, I'll be able to test the claims in person. The Linotype I will "dilute" with low-Antimony and/or no-Antimony Lead won't get to me until mid to late August (My buddy a few hundred miles away, who is giving it to me, will be bringing it in his SUV, versus shipping it, because the cost to ship the quantity he is giving me would be ridiculously high). At that point, I'll find out quickly if the claims are true or not.
Jim G
Correct, this is the preferred alloy of BPCR shooters if they can use the exact size bullet they want. 20-1 is softer and helps more with obturation. 12.5 BHN will work well. I shoot bullets that are around 12.5-13 and they work magnificently. Pedersolis are usually .459 and like .460-.461. Some people's Pedersolis will shoot .459 fine but mine does not with harder alloys. You will find it is no issue shooting 600 yds once you get everything dialed in.In fact, many shooters of "buffalo rifles", especially the Pedersoli models, suggest an alloy that is JUST hard enough to not lead the barrel, and up to .002" larger in diameter than the groove depth in the rifling of the barrel. The soft alloy helps the bullet to obturate easier for a snug accurate fit. Since I am going to the trouble of casting my own bullets, and want to try shooting the Pedersoli at up to 600 yards (the max range distance at my home range), THAT is what I am intending to go for!
Jim G
Ah, good to hear that I am on the right track! The RIGHT handmade 500g moderate velocity cartridges, coupled with the HiLux full barrel length 6X scope that mitigates my macular degeneration, SHOULD make decent 600 yard groups possible. I am still in awe of what buffalo hunters and U.S. Army troops were able to do with those Sharps and Trapdoor rifles back in the day.Correct, this is the preferred alloy of BPCR shooters if they can use the exact size bullet they want. 20-1 is softer and helps more with obturation. 12.5 BHN will work well. I shoot bullets that are around 12.5-13 and they work magnificently. Pedersolis are usually .459 and like .460-.461. Some people's Pedersolis will shoot .459 fine but mine does not with harder alloys. You will find it is no issue shooting 600 yds once you get everything dialed in.
I have wondered how Pedersoli can simultaneously say they broach rifle but still have a tapered bore.If your barrel is "taper" or "choke" bored, that helps immensely in obturatuon as it gets progressively brighter towards the muzzle.
Maybe not as much as you think. Buffalo range was typically 300 yards. The hunters wanted to stay out of sight, sound, and smell but still make good hits. Long range targets were typically large, larger that what we now shoot at.I am still in awe of what buffalo hunters and U.S. Army troops were able to do with those Sharps and Trapdoor rifles back in the day.
Yes, but using 20.5g of 5744 with the sample 500g bullets that a friend gave me to try, the Std Dev was THREE, and the very first 3-shot group at 100 yards was 1.1". Given that kind of start in ladder testing, would YOU change powders?5744 seems to have gone up significantly in price. At least 10 dollars more than even varget, no idea why....
I have wondered how Pedersoli can simultaneously say they broach rifle but still have a tapered bore.
Kind of like Harry Pope saying he taper bored his schuetzen barrels but did not "emery" them like most makers lapped in their taper or choke. And how did Elmer Keith's gunsmith "draw bore" his shotgun barrel to taper the full length instead of having a distinct choke?
I recently saw an explanation of how the Colt "silver ball" could polish a tapered bore. Strange.
. . .
If you only have one pound yes.... if you have multiple 8s because your all in no. I have 5 pounds of 4198 and that's a solid choice....Yes, but using 20.5g of 5744 with the sample 500g bullets that a friend gave me to try, the Std Dev was THREE, and the very first 3-shot group at 100 yards was 1.1". Given that kind of start in ladder testing, would YOU change powders?
Jim G
I would say in terms of decent grouping, 300 is about the limit of a Trapdoor. Sharps, obviously much more with scopes and vernier sights. At 300, I can keep my Trapdoor grouped in a 16" target. That is good enough in my book and from benchrest. Off hand, 200 or so is doable. I think it is important to remember than people back then didn't put a lot of thought into animal suffering to obtain their resources. 300 was about the limit to penetrate to fell the animal and wait for it to die or move closer later to finish the job. Catch and release and humane kills came along much later. I read somewhere that if whales and buffalo could have screamed in terror and agony over their killing by our long-suffering hunting equipment, then things might have been a little different.I have wondered how Pedersoli can simultaneously say they broach rifle but still have a tapered bore.
Kind of like Harry Pope saying he taper bored his schuetzen barrels but did not "emery" them like most makers lapped in their taper or choke. And how did Elmer Keith's gunsmith "draw bore" his shotgun barrel to taper the full length instead of having a distinct choke?
I recently saw an explanation of how the Colt "silver ball" could polish a tapered bore. Strange.
Maybe not as much as you think. Buffalo range was typically 300 yards. The hunters wanted to stay out of sight, sound, and smell but still make good hits. Long range targets were typically large, larger that what we now shoot at.
Surprising it is that small for groove diameter. Are you sure that is not bore diameter? Groove diameter is more and this is what you are trying to fill. With soft lead you typically only need .001 to .002 over groove diameter or the same diameter with harder alloys.I just picked up the Pedersoli from the gunsmith. The slugging apparently showed the bore grooves to be .4563" diameter. So, a .458" or .459" sized diameter bullet should be optimal. a .460" sized bullet would be .0037" larger than the groove diameter. That would be TOO snug a fit, even with a soft lead bullet, right?
Jim G
I just picked up the Pedersoli from the gunsmith. The slugging apparently showed the bore grooves to be .4563" diameter. So, a .458" or .459" sized diameter bullet should be optimal. a .460" sized bullet would be .0037" larger than the groove diameter. That would be TOO snug a fit, even with a soft lead bullet, right?
Jim G
I just re-checked with the gunsmith. That is the groove diameter, not the land diameter,Surprising it is that small for groove diameter. Are you sure that is not bore diameter? Groove diameter is more and this is what you are trying to fill. With soft lead you typically only need .001 to .002 over groove diameter or the same diameter with harder alloys.