Gas check and the 310 Lee

[jules]

I bought a used 44cal Lee 310gr mold. It came with aluminum gas checks but they are so darn big they take no force at all to seat them and they will not fit in the Lee size die. They say 44 caliber on the package but don't seem to fit. Should I try a different brand or maybe use the copper ones?

[Iowa Fox]

Get some gator checks from Blammer. They fit my 310 the best.

[historicfirearms]

I recently bought that mold and the gas check shank was small. Hornady and Blammers checks were very loose. I wound up lapping the check shank along with the driving bands to make them bigger.

[jules]

.405 is my shank size

[HollowPoint]

If you haven't already, try running your bullets upside down through you Lee sizing die with the loose fitting gas check in place.
If this gives you slightly rounded bases on your gas checks, then run them right side up and your sizing-die-punch will flatten
out the base.

Personally I'd lap the Gas-Check-Shank on my mold as has been suggested. That's the quickest fix I can think of.

HollowPoint

[jules]

I tried running the GC through the sizer and I didn't want to put that much force on the ram. These GCs would not fit in the die.

[jules]

If you haven't already, try running your bullets upside down through you Lee sizing die with the loose fitting gas check in place.
If this gives you slightly rounded bases on your gas checks, then run them right side up and your sizing-die-punch will flatten
out the base.

Personally I'd lap the Gas-Check-Shank on my mold as has been suggested. That's the quickest fix I can think of.

HollowPoint

What are you using to Lap the shank?

[historicfirearms]

I used fine valve grinding compound embedded on a boolit. Take a boolit cast from your mold and drill a small hole in the base for a wood screw to go in. Cut the head off the screw so you can chuck it in your hand drill. Next, embed the grit into your boolit by rolling it between two pieces of plate steel. Be careful to only get the grit on the part of the boolit that you want to enlarge. Now, spin the boolit in your mold. Once you think you've done that enough, clean the mold of grit. I will usually polish the cavities with some Flitz or similar polish with another boolit spun in the same way. Go cast a few boolits and check progress. You will usually need to do this a few times to get the diameter you want.

[jules]

I ordered some Hornady's. Will see how they work out before I do any lapping on the mold.

[jules]

Got the Hornady's and they seem to work fine. I can turn them but can't pull them off. I may just open the shank a bit. I don't want to ruin the mold. Thanks for the info.