Thickness?

[BulletFactory]

New-b question here. I' new to gas checks anyhow...

I ordered a 31-170BG from Accurate molds, and I don't know what thickness of gas check I'm supposed to get. I'll be ordering a gas check die, and was about to order some metal, but I dont know what thickness I need.

http://www.accuratemolds.com/bullet_...31-170BG-D.png

Thanks.

[elwood4884]

BulletFactory, You will need the gas check shank thickness and bullet sized diameter to determine metal thickness.

[elwood4884]

Thickness = (sized diameter - shank diamter )/2

[BulletFactory]

What is this shank you speak of?

[elwood4884]

The shank at the base of the bullet where the gas check snaps on to

[BulletFactory]

Oh, I thought it was the piece that went in the head of the ram on the press, that is used to push the bullet through the sizing die.
Looks like the part where the gas check fits on the boolit is .284". I don't have the rifle from the gunsmith yet, so I dont know the bore diameter. Most people are at .311 with these rifles. It's an M1A with an 18.5" barrel, semiauto 1-11 twist, 4 grooves.

[JeffinNZ]

You will want at least .014 material. I like to go a spot thicker as the heavier material extrudes as it forms and makes for a perfectly formed check. Crisp.