Odd sized gc's. Maybe?

[littlejack]

Gentlemen:
I have been gas checking some of the 316299 boolits that I aquired through a trade. There seems to be 2 (two) makes and sizes of gas checks that I swapped for.
The ones that fit good on the boolits are approximately .286 i.d. and .319 +/- o.d. with a thickness of .017.
The other checks are about .281 i.d. and .307 o.d. and a thickness of .013.
Can someone clarify if the smaller checks are for a particular size boolit. I am not using these on my boolits, as they are too small for my needs. If someone is interested in this particular size of gc, I would be interested in swapping for the larger size for my boolits.
Jack

[Ben]

Sounds to me like it is all about the thickness of the Check material.

[littlejack]

I realize that the latter gc's are of thinner material, but the I.D. dimension is also smaller.
Jack

[Ben]

WHO made the gas checks ?

[littlejack]

I do not know.

[Ben]

The checks that are .286 i.d. and .319 +/- o.d. with a thickness of .017 clearly are the closest thing to a proper dimensioned gas check for a standard 30 cal. gas check bullet of the 2 different types that you have.

I have no idea what the other one ( .281 i.d. and .307 o.d.) would fit ?

Ben