View single post by Tsquare

Posted: Mon Feb 5th, 2018 10:42 pm

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Tsquare

Joined: Fri Nov 10th, 2017

Location: Suwanee, Georgia USA

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But the problem with commercial NATO standard is that it ain't. You wont find SAAMI specs on 5.56x45. The military standard (MIL-C-63989 Rev. C) for M-855 is 3000fps plus or minus 40fps at 78 feet from the end of the muzzle with a 40 fps standard deviation. Which is also the NATO standard.

Lake City has 62gr M-855 listed with 3,020 fps. IMI has their 62gr M855 listed at 2817 fps. I have chrono'd LC M855 and got 3028 fps. I was using an 18" barrel instead of the mil spec requirement of a 20" barrel which should pump it up a little bit more. But I was also measuring 10 to 15 feet from my muzzle.

I have not chrono'd IMI M855 and I have a few boxes of it. I am planning to go to the range tomorrow and I will chrono a box to see what it is running.

On a side note, I load my .223 a half grain below recommended max load for the powder/bullet weight combination and I am averaging 2890fps with a standard deviation of 28 fps. It gives me a 3/4" MOA. I am spot on with what my reloading manuals say I should be getting with my .223 but I seriously doubt I am loading hotter than IMI M855.

Last edited on Mon Feb 5th, 2018 10:43 pm by Tsquare

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Tony
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