I have an interesting observation/problem. I am reloading some .308 win with cast lead bullets and I did two separate lots, one lot with hornady brass and one lot with winchester nickel brass. I sized them both with the same Whidden die and same expander. But when I seated the bullets, the hornady brass shaved the lead bullets a slight bit while the winchester brass did not. Can anyone explain this phenomenon? I am guessing the winchester brass is softer, but unsure. And, as a corollary, how do I fix the problem on the winchester brass? Again, I am guessing with a larger expander ball. Lastly, which route would be better larger expanding ball or softer brass, if indeed those are the issues.
Lead bullets shaved by case mouth
- Thread starter rulellis
- Start date
Probably differing hardnesses between the two different brands/lots of brass.
Most likely the easiest solution isn't necessarily a larger expander, per se, but actually flaring the case mouth ever so slightly. My understanding is that this is fairly typical for cast bullets. Lyman makes an 'M' die, basically an expander mandrel with a stepped section so that when you screw down the expander, you can set it to just kiss and slightly 'flare' the mouth to better accept cast bullets without shaving the bases. Alternately, Lee makes a Universal Expanding die which does just the latter 'flaring' action. Of course then you'll probably want to lightly crimp the case mouths post seating - not so much for a real 'crimp', but to smooth out that little 'flare' and ensure smooth feeding into the chamber.
Most likely the easiest solution isn't necessarily a larger expander, per se, but actually flaring the case mouth ever so slightly. My understanding is that this is fairly typical for cast bullets. Lyman makes an 'M' die, basically an expander mandrel with a stepped section so that when you screw down the expander, you can set it to just kiss and slightly 'flare' the mouth to better accept cast bullets without shaving the bases. Alternately, Lee makes a Universal Expanding die which does just the latter 'flaring' action. Of course then you'll probably want to lightly crimp the case mouths post seating - not so much for a real 'crimp', but to smooth out that little 'flare' and ensure smooth feeding into the chamber.
Lee makes a universal expander die with a conical expander that flares the case mouth like pistol dies do. It works on any length brass, any caliber. $15
https://www.midwayusa.com/product/1012078542/rcbs-neck-expander-die-308
Using a case neck expander should eliminate this problem.
Using a case neck expander should eliminate this problem.
In my experience, yes, flaring is an extra step. It could be used in lieu of an expander ball in the FL die if it's a Lyman "M style" die, depending on how much neck tension you're after.
The nickel brass could be softer or thinner necked, chamfered more, or any number of subtle differences.
The nickel brass could be softer or thinner necked, chamfered more, or any number of subtle differences.
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I use a Lyman type M die and flare the case. Then I use a Lee crimp die (the collet style) to get rid of the flare. I did about 500 rds with lead gas checked bullets to use as fireform loads for my 260 AI. Without flaring I was shaving lead constantly. After setting up the M die that disappeared. Worked great.
