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Dan Cash
12-19-2008, 01:32 PM
I am in posession of a grand quantity of pure lead and use it for BPCR at 20:1 or 30:1. How do these alloys compare to straight wheel weight (which I don't have). I will cast for various smokeless rifle and pistol caliber at medium velocity for caliber and, of course, can alway make the alloy harder.

Thanks in advance,
Dan

montana_charlie
12-19-2008, 01:56 PM
How do these alloys compare to straight wheel weight
Tin helps fillout, adds a minor amount of 'hardening', and reduces the melting temperature of alloys. Your 30-1 and 20-1 mixes are considered to be 'soft' alloys, and are (relatively) 'rich' in tin.
For that reason it's easy to get beautiful bullets without overheating the alloy.

30-1 has a BHN rating of 9, and 20-1 is BHN 10.

Wheelweight alloy is 'poor' in tin, so it requires more heat to melt...and more heat to fill a mould reliably.
It could probably be called a 'semi-hard' alloy, and the antimony content allows it to be further hardened by manipulating the cooling rate.

It is ususally considered to have a hardness of BHN 12, but that varies enough to make the number rather misleading. Some form of hardness testing is almost a requirement if you need a 'number you can bank on'.
CM

Larry Gibson
12-19-2008, 04:18 PM
I find a mix of 50/50 WW/lead to give pretty much the same accuracy at the same velocities as 20-1 alloy. Expansion charactorisics of the 20-1 is a little smooter as it seems somewhat more maleable. Not enough difference to get excited about though. I use both but actually prefer 16-1 alloy for higher velocity (1400-2000 fps) hunting loads with GC bullets. However, the 50/50 WW/lead alloy is also a good one.

BTW; I do not use these alloys for general shooting or practice at the higher velocities. These are alloys for hunting loads only. Straight WW + 2% tin is very good for general use up through 1800 fps +/-.

Larry Gibson

missionary5155
12-19-2008, 05:19 PM
Greetings I have several Rollers in 2 calibers. My 43 Spanish will shoot 30-1 far better with Black 2F IF i am using an undersize boolit. That throat NEEDS a .443 boolit minimum to to use WW but if it is .444 up to .446 it does as WELL and that is what I generally use.
My other 2 Rollers are 45-70. One is a custom Bausky Barrel at .458 all the way down. The other is a Pedersoli at .456 all the way down. Those rifles shoot any mix that is sized +.002 over bore EXCELLENT.
Now my 1884 Trapdoor is another critter. It does NOT like WW even out of my oversized Rapine mole (.464) nor any mold style or diameter I have tried. It likes Pure lead +tin ! It shoots PURE LEAD and 30-1 = using 2F and 25-1 a bit better with Smokeless. But It just does not shoot WW better than "minute of paper plate" at 50 yards. Different rifling style.. depth.. wear.. it all seems to matter
My 38īs fairly follow the same pattern. The better the throat /bore it does not matter. Throw in a barrel with "character" and lead+ tin works better.
My thought is.. What is your throat area diameter and condition and bore ? The rougher it is or the more you have to "Bump Up" the boolit to fill the throat the better off you are with a pure lead + tin mix. If the bore is rough.. pitted.. shallow rifling start with the purer lead combinations. WW is pliable under higher preasure but Black and smokeless lower pressure loads just do not seem to be able to work well in callanging barrels.

runfiverun
12-19-2008, 06:50 PM
the 30-1 and 20-1 will do plenty your rifle loads may be somewhat limited but for your pistol load and midrange rifle loads to bout 1700 or so, the mixes you have will work fine i have shot quite a bit of 20-1 alloy,and it pushes along just fine.

Dan Cash
12-19-2008, 11:58 PM
Thanks a bunch fellows. I have a good bit of experience with the lead and BP but little with smokeless and any cast bullet. You have certainly answered my question(s) in a most understandable manner.