trouble with aluminum check

[400short]

I bought some aluminum checks for pb bullets. I tried installing them on already sized and lubed bullets from an rcbs 250 gr. Keith style mold. They were sized to .430. I'm using the lee sizer. Running them through nose first, the sides of the check tear off and end up on the die punch. Running them through base first, they seat and crimp on tight, but aluminum smears over the lube groove. I've tried to lube the check with a lanolin based lube, but no change.
Has anyone figured this one out?

[Dryball]

What are your checks made out of (pop cans, flashing, etc) and what is their thickness? Sounds like your checks are too thick for PB's

[Stephen Cohen]

I would hazard a guess that the Lee sizing die is a little rough inside and needs polishing. I have a few newer ones that suffer this problem, the quality has really dropped over the years.

[Sagebrush7]

The Lee sizers have a sharp entry mouth.Take a cone shape stone and gently ease the mouth of the die and polish with 300 grit paper.

[Dan Cash]

Best solution is contact Richard Dooughty (forum sponsor) and purchase your sizers from him. Price is competitive with Lee and quality is something Lee only talks about.

[Bullshop]

If your putting a check on a PB boolit sized to .430" and then running that through a .430" sizer die then something has to give. It has to either swage the boolit base diameter down to iron the check on or the check itself must be displaced as seems to be happening.
Maybe a softer alloy to allow the swaging of the boolit base instead of the displacement of the check material?
Personally I think it a waste of time because I feel if both the aluminum checked PB and the non checked PB of the same alloy can be used to the same accuracy and velocity level with proper load development. Bash my position on the matter if you must but its my opinion based on my experience which is likely more extensive than that of any that may dispute it.

[pistolman44]

I'm having the same problem with aluminum PB GC with the metal flowing too much up the bullet when sizing and with half of them tearing. I'm not fooling around with PB, I'll just have a mold made in the same weight as the plain base but with a standard gc shank.