Cartridge & Headspace Specifications: .308 Win / 7.62 NATO

[Roadkingtrax]

NATO doc, STANAG No. 2310 has everything you need to know Sapishka. Overlay those chamber dimensions onto the SAMMI .308 spec...

[Big_Red]

Alright, cleaned up as best I could without losing the gist of the point/counter-point, which ironically are the same and support each other, i.e.--the NATO brass is heavier because it is often thicker (NOT wider), particularly near the base. Also confirms the exterior dimensions of each cartridge are the same. As clearly noted, it is the length of the chambers that can differ.
Words were getting in the way of the message.

I've modified the OP to clarify the exterior dimension point, and worked with Norman to actually post the dimensions themselves so they are right there for everyone to see/reference.

For supplementary info, when I get a chance, I will pull down a NATO cartridge and a SAAMI cartridge (each from the same respective lot), then fire another one of each from the same rifle, then cut the brass in half of all 4to compare and demonstrate graphically the similarities as well as the difference in thickness.
If someone already has that, please...post away.

And please note that any further posts that are purely subjective speculation and/or derailing the thread will be deleted.

Thanks for your support.

[johnfg]

Still some things about headspace that I don't understand. The fired cases from both my Winchester model 70, and my son's Ruger American are virtually the same. Headspace measures 1.621, which is less than the minimum (as I read and look at it) on the Saami drawings. Saami shows on the cartridge drawing: 1.634-.007. Even brand new Remington brass measures a headspace of 1.620! Please help me to understand when comparing the drawings and the specifications, to the actual headspace. Regardless of the drawings, I've been setting the headspace back about .002.

Thanks for any help and/or explanations.
john

[normannewguy]

Originally Posted by johnfg

Still some things about headspace that I don't understand. The fired cases from both my Winchester model 70, and my son's Ruger American are virtually the same. Headspace measures 1.621, which is less than the minimum (as I read and look at it) on the Saami drawings. Saami shows on the cartridge drawing: 1.634-.007. Even brand new Remington brass measures a headspace of 1.620! Please help me to understand when comparing the drawings and the specifications, to the actual headspace. Regardless of the drawings, I've been setting the headspace back about .002.

Thanks for any help and/or explanations.
john

Very tight for a 308 WIN chamber, most are min 1.630 and ammo at 1.628. I would try a go gage 1.630 and see if it chambers. If it does I would double check how you are measuring it . Have fun and be safe