Keyhole Problems

[Rocky Raab]

Heck, I'm ALWAYS right in all aspects, LOL!!!!!

The pure lead bullets are simply too soft. They "wipe" off lead in the rifling like a stepped-on Popsicle on a hot concrete walk.

Now, understand that MOST cast lead bullets are too hard -yeah, I know...contradiction. But when I say that, I'm talking about handgun bullets. RIFLE bullets are (or need to be) much harder than handgun projectiles. It's a gas pressure thing.

If you divide the maximum pressure of a load - and it matters not if you use CUP or PSI - by 1400, you'll get the "best" BHN for that load. I put "best" in quotes because a lot of other factors like lube, gas checks, bearing length, powder burning temps and such, come into play. But generally speaking, you won't go wrong with that formula.

In the great old .303, you are probably running near 36,000 psi/cup (I had to use 30-06 data, but it can't be far off) with 13.5 gr of Green Dot. So, the correct BHN would be 36000/1400 or almost 26. That's higher than almost any lead alloy you can obtain.

Translation - you gotta gas check those bullets.