6.5 Grendel Proof load or "Blue Pill"

[Mopardoctor]

Does anyone use a proof load on a new build or is this just "old School" gunsmithing?

Mopar Doctor

[Sticks]

I had to look that one up.

First that I have heard of it. Likely that when using a new barrel+extension, you are using components that have already been "Tested" by lot, so not much reason to do it again.

Bolt actions however, especially in Wildcats, I would think that it would be prudent to have it tested....but that may be the point in Wildcatting(?)

[Mad Charlie]

Maximum Average Pressure for the 6.5 Grendel has already been established.
Why chance damaging expensive parts?
Even though no visible damage may be apparent, tiny cracks might get started that fail later.

[LRRPF52]

AA uses proof loads for testing.

I think there was a certain percentage of every lot of bolts that were destructively tested.

Proof load at 67,000psi, followed by machining the bolt face and immersing in resin to analyze grain structure of the steel in every batch.

Bill Alexander set up a lot of test protocols based on years of experience in the industry and with the Ministry of Defense, working with various firearms manufacturers and component suppliers.

Bolts that you get aren't proof load tested, because it causes microscopic cracks to form that will only propagate with time.

Knights Armament does something similar or the same I think, as does Colt Canada.