Name That Thread

[piggy589]

I've been given a used muzzle thread protector ring.

Ten mil. deep with six threads,I make that fifteen fifteen t.p.i..

Any idea what thread it has?

[DCL_dave]

If it is metric then 1.75mm pitch would give 14.51 tpi ...could it be m12 x 1.75mm?

[piggy589]

If it is metric then 1.75mm pitch would give 14.51 tpi ...could it be m12 x 1.75mm?

Oops,I forgot to mention, it's got a half inch inside diameter,but thank you good sir .

[DCL_dave]

Oops,I forgot to mention, it's got a half inch inside diameter,but thank you good sir .

Lucky guess then!

[TORNADOS7]

Wouldn't be a .5" UNF by any chance ?...

[DCL_dave]

Wouldn't be a .5" UNF by any chance ?...

Could be, but its 20 tpi for UNF and 13 tpi for UNC in 1/2"....

is it old?...could be BSF at 16tpi in 1/2"?

[deejayuu]

Probably reading this wrong but if "half inch inside dia." then can't be half inch any thread.
5/8" BSF is 14 tpi if not mistaken and near 1/2" core dia.

[piggy589]

Could be, but its 20 tpi for UNF and 13 tpi for UNC in 1/2"....

is it old?...could be BSF at 16tpi in 1/2"?

1/2" BSF would appear to be the closest estimate .