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Keyholing: 9mm lead 147gr. rcbs flat nose/flat base

2375 Views 17 Replies 6 Participants Last post by  Duhbob
Keyholing: 9mm lead 147gr. rcbs flat nose/flat base

My flat nose RCBS ww 147gr.bullets look great and fly like a tipped pass from a bad thrower. I had temporarily lost my source for the functional/useable 136gr rnl bullets I am using now. So I had to do something...I ordered the $67 mold and cranked out 1,000 lead bullets...They suck!
I got my 136gr. source back so I can gladly say I am ok again BUT STUCK with a mold that I can't use.
The problem is KEYHOLING even at 20'. I tried N-340' N-350 and aa#7 also .356, and.355...nothing helps not lighter/heavier crimp or long or short OAL. I am loading pretty light stuff, like 133 power factor. Who wants to chime-in, anybody who loads lead 9mm from wheel weights ??
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Re: Keyholing: 9mm lead 147gr. rcbs flat nose/flat base

No offense, but have you slugged the barrel? I'd also suggest miking the bullet across its' other axis and through a couple 'rotations' to "prove" the bullets are round.
Re: Keyholing: 9mm lead 147gr. rcbs flat nose/flat base

Beladran said:
hmm are you using straight WW's? To me if they are dropping from the mold at .357 and your sizing them down to .356. thats not much. you need to spike the mix with some extra tin to try and get them to at least .358
More tin and antimony makes them drop bigger and harder
More lead makes them softer and smaller but heavier
I agree with this completely. I mike after I lube and size; I cast .003" over, and size to .001" over, and that's the regimen I generally stuck with unless I couldn't find reasonably-priced molds in my desired size.

The range of my ratio of lead to tin was more towards 93-7% or 95-5%. I was never real precise with my ratio--I only stopped adding tin when I was absolutely positively sure I'd added enough to easily surpass 5% tin. My bullets were really hard and usually light, falling short by 1/2 - 1gr per 100gr bullet. Then again, all I used them for was target-shooting or steel plate, not hunting.

Slowing them down might help, too if you don't wanna change your tin content. Mine was high because I wanted at least 900fps out of my bullets.

to miking and measuring--I only ever checked my bullets for roundness when I took delivery and used a new mold for the first time or did the same with a new sizing die.
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