Something as new as Creedmoor would probably be okay.
Something like .300 Blackout, that doesn't have a SAAMI standard, no.
Something as new as Creedmoor would probably be okay.
Something like .300 Blackout, that doesn't have a SAAMI standard, no.
300 Blackout is SAAMI.
I don’t have any brand mixing concerns, but I do require the actual number on gauges.
So does SAAMI actually approve headspace gauges for anything? When I tried looking it up, I found this FAQ:
https://saami.org/faqs/#1622648797091-fd1263a1-69ea
My read is that SAAMI defines min and max chamber lengths, but it’s up to the firearm manufacturer to decide where within that range they want their chambers to land, and to gauge accordingly. And the notion of a “field gauge” is explicitly not endorsed.
Look up the 2015 (or later) editions of the SAAMI Z299 Series, Voluntary Industry Performance Standards for Pressure and Velocity
Z299.1 - Rimfire
Z299.2 - Shotshell
Z299.3 - Centerfire Pistol and Revolver
Z299.4 - Centerfire Rifle
Headspace gauge data starts on page
Z299.1 - 70 (77 in .pdf)
Z299.2 - 101 (108)
Z299.3 - 122 (131)
Z299.4 - 212 (224)
Just like "mil-spec" . . . . meaningless marketing.
SAAMI does not have a specification for a .300 Blackout headspace gauge, they only specify the chamber dimensions. This is why multiple manufacturer's could have multiple gauges with slight differences, such as tolerancing, finish, material, hardness, etc . . .
AND, there is no such thing as a 5.56mm NATO headspace gauge.
There are M16 gauges
There are M249 gauges
There are M27 gauges
etc.
Wide? Go and No-Go have to be within the 0.010” chamber depth tolerance of SAAMI or they are not 300BLK gauges.
Insist on gauges with the actual headspace number, so you will know how much less than maximum the No-Go (likely) is.
Field gauges are a relic of the past like proof load testing, when poor designs, questionable material and hardening processes were the norm.
Bookmarks