Round ball hardness

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Hesp

40 Cal
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Does the hardness of the lead in a RB have any effect on accuracy? I have a Lyman Great Plains 54 cap lock, 1/60 twist. When I mix pure lead , (about 6 on my Brinel tester) , 50/50 with scrap wheel weights ( Brinel about 10.5 ) I get a Brinel hardness of about 8. These harder balls show a very definite increase in accuracy at 100yds over pure lead balls in my rifle. . Anyone else given this a try ?
 
If it works for you and it repeats, great.

I have limited casting experience, but have found that alloys will cast slightly larger that pure lead, giving a tighter fitting patch and ball combination if you are using the same patch material. You may want to try a thicker patch with the pure lead and see how they shoot. Also, with my hardness tester, ‘pure’ lead is typically 5BHN or a little lower.
 
Lead hardness can vary some. Also the brand of hardness tester can vary a bit also. My tester is an LBT brand. Yes they will ( RB ) cast slightly larger but not enough that I have seen to make a big difference. The big difference I see is with accuracy. In particular, 100 yd accuracy.
 
Lead hardness can vary some. Also the brand of hardness tester can vary a bit also. My tester is an LBT brand. Yes they will ( RB ) cast slightly larger but not enough that I have seen to make a big difference. The big difference I see is with accuracy. In particular, 100 yd accuracy.
A larger roundball will load tighter. Tighter patch and roundball loads typically are more accurate than looser loads.

When I experimented using different alloys with roundballs, I found that I needed different patch thicknesses with some for loading easy and accuracy.
 
Makes sense to me. A RB has a very limited amount of contact with the rifling. Snugger fit , more likely to have reduced slip = better accuracy.
 
i normally shoot .530 with a .015 patch.
got some .535's from midway during their sale and have been shooting them with a .010 patch.
same overall end dimension. yet the .535s shoot more accurate.
now my take on that is the ball is closer to contact with the rifling. when fired it obturates just enough more to catch the rifling. though the fired patches aren't cut at all so:dunno::dunno:
now these are swaged pure lead.
just for S&G's i grabbed a couple alloyed balls i use in my ball mill.
they are BN 15 hard. thought i would break my rammer loading them with a .010 patch
they shot 2 inch 5 shot group at 25 yards. not any better than my dead soft balls shot.
recoil was just a little more.
 
I have done extensive testing on lead hardness, and bullets for my muzzleloaders.
I started out with pure and slightly hardened them. I use a cabine tree hardness tester.
For my 50 cal's I settled on .038 to .042 on my tester. That's 6 to 7 bhn.
Then I tested them for expansion. In 2009 I took the first animal and have been very successful.
I went on to expand my testing to 45 cal and began using it for hunting. The 45's are hardened to 8 to 9 bhn.
Many times a addition of alloy can have benefits. Both accuracy and terminal performance.
The most important part is being able replicate the process of hardening.
 
I ran a bunch of .530 ball out of some 20:1 lead/tin. Not on purpose, I used the wrong ingots. If they shot any different, I couldn't tell. They did load a little harder.
 
I cast minies out of 20 to 1, but I'm a heretic. The minies shoot great. Admittedly off topic, but a wee bit of tin helps with casting anything. My RB alloy is about 100 to 1, flows like water at 750 F.
 
At 50 yards I saw no difference between balls cast from scrap pipe (bhn 6) and balls cast from my range scrap (bhn 9), but that's not much difference in hardness, not much distance either.
 
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