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M855A1 downcharged to 57,500 psi?


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I have read claims on other forums that the US Army has had the manufacturer adjust the propellant used in M855A1 so that its chamber pressure is 57,500 psi, down from 62,000 psi.

Some quick Googling failed to bring up a reputable source confirming this, but my Google-fu is known to be deficient.

Does anyone know if it's true?

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62k psi is meh.  Do the math for bolt load.  I'm on a phone, otherwise I would.  Match shooters fairly consistently run 75 and 77gn projectiles at 2800-something from 20inch service tubes.  Primers don't start to go away until 70k plus.  I used to run 69 SMKs at chrono'd 3040fps, with no pressure signs, just change bolts every season as a precaution.

That said, I've heard nothing about it.  It seems stupid, so it might well be true.  S/F....Ken M

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23 hours ago, EchoFiveMike said:

62k psi is meh.  Do the math for bolt load.  I'm on a phone, otherwise I would.  Match shooters fairly consistently run 75 and 77gn projectiles at 2800-something from 20inch service tubes.  Primers don't start to go away until 70k plus.  I used to run 69 SMKs at chrono'd 3040fps, with no pressure signs, just change bolts every season as a precaution.

That said, I've heard nothing about it.  It seems stupid, so it might well be true.  S/F....Ken M

Thanks! 

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