% tin?

[beng]

Have a quick question about what % of tin to use in my casting.   I have a Remington rolling block #1 on a NEW Greenmountain heavy barrel, 34", 1-18 twist.  I use smokeless powder and cast a Brooks 535 bullet.   I have been told to use from 20-1 to 40-1 lead.   We go out 200 to 500 yds. (At the present time)   Thanks for your time.     beng

[mechanic]

I will make an assumption that you are shooting 45-70?  If so at the velocities you shoot it, the lead does not have to be very hard.  I've shot pure lead at those velocities from in line muzzies with no issues.
 
Straight wheel weights are sufficient for most uses and firearms, and this is what I shoot in just about all my centerfires.  If I'm pushing something fast, I use a gas checked bullet.  Experiment a bit, and just find what works best for your use.
 
Ben

[Nobade]

If that Brooks bullet doesn't have much unsupported nose then 20:1 should work great. If it has a long nose like a "money" bullet you might want to go to 16:1 to keep it from slumping too much. After a few hundred pounds of bullets fired you'll have a pretty good handle on what your rifle likes best.

[beng]

Sorry about that,  it's a 45-70 with a 535 Creedmoor bullet.    beng

[Lloyd Smale]

im far from an expert at black powder cartidge shooting but my buddy does a ton of it and what he mostly uses is 20-1