An open question to Pat Marlin

I made a couple thousand .32 PB gas checks right after receiving my die. 90% are made from Pepsi product cans. 10% from Coca-Cola product cans. The local Pepsi bottler uses a thiner can than coke. I just started casting 80gr .32 cal bullets using Lyman's mold. I seated the checks using my Lyman 450, Lyman gas check seater and a .311 H&I die. Then I went back to size and lube. At this stage 50% of the checks (all Pepsi cans) tore the base of the check from the side either partially around the circumference or all around it. The later case causing me to have to fish the base of the check out of the H&I die.

The few bullets I tried seating and sizing in one stroke seemed to have a lower % of these failures. The bullets I sized and lubed then seated the check had the least %.

I did not experience this with the 9mm checks.

Have you encountered this before? If so what was the solution other than what I experienced? I really hate wasting work/parts.

A second problem I have had with all of my PB dies is when forming the cup the disk will be centered in the depression but the cup will turn out slightly lop sided. (not pop sided) This seems to add to the incidence of the above problem. Any fix?

=#÷%" auto correct.

"the cup will turn out slightly pop sided. "

Well, you started out by telling us that you were using both Coke and Pepsi containers.

Sorry, I couldn't help myself.

Ar ar ar ar.

Moderator please move this to gas check making.

so moved...

How hard are your boolits?
PB checks need to be installed onto boolits made from a fairly soft alloy...COWW or harder will be troublesome.

also, how sharp are the edges on your .311 H&I die ?

"A second problem I have had with all of my PB dies is when forming the cup the disk will be centered in the depression but the cup will turn out slightly lop sided. (not pop sided) This seems to add to the incidence of the above problem. Any fix?"

you say "centered in the depression"
Is it sitting in the top portion of the form die or the bottom of the form die?
when I shear the disks, if I only shear one thickness of popcan, I usually get a small 'tag' on one side. If they have that tag, they will sit in the top portion of the form die and may look like it's seated flat, but it ain't if it's making a lop-sided GC. Cutting two thicknesses has solved that problem for me...also, be sure to keep the cutting edge of the die clean and lubed, also be sure to keep the cutting edge of the punch sharp.

I punch 2 layers and lube often. I've seen the tag a few times and toss them. No these are down in the provided depression. They just seem to jump a little, once in a while.

How do you sharpen the edge?

My alloy is 6%2%. My die is very used so a slight bevel has been worn on the edge.

I sharpen the punch with a red (600grit) Eze-Lap Diamond Hones.
http://eze-lap.com/products/diamond-hone-stone/
if the edge of the punch is worn, you may need to start with a more coarse grit hone.

6% Sb is pretty hard...Depending on how much oversized your boolits are, I could see the popcan GC shearing during seat/crimp?

I do know that most Lyman and RCBS sizing dies need a more gradual taper at the opening of the die. It also needs to be larger at the opening for plain base checks to size on. After all the gas check adds .008 to the bullet dia. before sizing. that's with pop cans, more with other material. One thing you can do is size your bullet first and then add the check and size again. Also try to get some sort of lube on the bullet as you size on the gas check. That will ease the passage. I have dealt with this for years and made / sold a lot of plain base gas checks.
n.h.schmidt

Another reason to go with one stroke/one gas check punches. Adding steps in between always adds to chances of possible errors, be it human or the tool.

Sizing & lubing first solved the problem. If the bullet is canted slightly in the sizing die it still shears the check.