Need help with gas checks...

[ShooterAZ]

I recently purchased a new mold...a Lee C312-185-1R. I am having problems seating the gas checks. They won't easily start by hand on the shank, and about half are not seating all the way...to the point of leaving the top lube groove dry. The checks are Hornady 30 CAL, I am sizing to .311. The alloy is Lyman #2, cast at 725 deg. I am using an RCBS LAM2. Anybody have any suggestions??? Thanks!

[Wally]

The GC shank is a bit too large...I had that problem with a 7mm 168 grain RCBS bullet. I drilled a hole just big enough to insert the bullet into a block of pine--3/8" deep. Put the bullet nose first in the hole then place the GC on the GC shank and lightly tap it "home" with a small plastic mallet. I did not do well with a Lyman 450 and the GC seater as the noses would be deformed. While this method first appears unorthodox...it worked just fine. I now make my own GCs and no longer have the problem...

[Wayne Smith]

Your alloy should be hard enough that you can use the Lyman GC seater plug which will also work with your LAM2. You may have to anneal your checks.

[wallenba]

Have you tried putting the check in the sizing die, then sizing the boolit over it. It might just force the shank into the check. Counter-intuitive I know, but it works with some of mine.

[grouch]

I've had success by setting the gas checks open side up on my table saw table and expanding the opening by placing the head of a round head wood screw(#8, i think for 30 cal) in the opening and giving it a light tap with a 16oz hammer.

[ShooterAZ]

I've had success by setting the gas checks open side up on my table saw table and expanding the opening by placing the head of a round head wood screw(#8, i think for 30 cal) in the opening and giving it a light tap with a 16oz hammer.

I just tried this method and I think it is going to work. Thanks to everyone for the advise!

[.22-10-45]

Hello, ShooterAZ..I have this problem with .22 bullet shanks. you might look for different sized ball bearings...sometimes just the right size will bottom out inside check & expand check to right amount.

[44man]

I also have trouble with some molds so I made a check set die. Getting the check all the way on before sizing is best.
I also have loose checks on a few boolits and found a Lee FCD will crimp the check. Mostly I will lap the check area of the mold to tighten them.
Some are so close I just tap the check on, on my bench top.