I ran into a deal this spring on a couple cases of "visual 2nds" MK318 MOD1 direct from the factory. As you can see from the pictures below, it's appears very similar to MK318 MOD0 ammo, except for the silver colored bullet. I sorted every round and came away with a handful of rounds that had moderately dented necks and discarded them.

There's not much information available about this "improvement" to MK318 MOD0 but there is this article out there that details a few differences.

I wanted to see how MOD1's velocity stacked up to the well known velocity performance of MOD 0 ammo so I ran a test. 10 rounds each out of an 11.5" barrel and a 16" barrel, both 1:7 twist.

The Ammo:

Mod0 is in the box and the MOD1 is on stripper clips:

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A picture from the Federal bulk case denoting it's factory 2nds ammo with "visual" as the defect:

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There were two different headstamps in my cases, FC 17 and FC 18. Primers are crimped and sealed. Case necks are also sealed.

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The Chronograph

MasterChrony, 12 feet from the muzzle.

Atmospherics:

Air Temp: 65 degrees
Humidity: 77%
Dewpoint: 55 degrees
Pressure: 30.02
Elevation: 1030'

The Results:

I calculated average velocity, extreme spread and standard deviation using Excel.

Attached File


Both rounds got moving pretty well!

Awesome work! Thank you

Hopefully others will be able to provide gel tests and sectioned bullets in the future

nice to see it got more consistent in velocity.

will mod 1 ever be for sale commercially though?

Who knows? Personally, I hope there's an overrun of several million rounds of MOD1 that will be released since M855A1 is the flavor du jour. Then again, it would be nice to see M855A1 at $10/box.

Interesting, could the velocity increase be due to less friction caused by the nickel plating?

Blue Falcon has a box and should be working on some tests soon.

Awesome! I was going to test Mod 1 tomorrow (Sunday) out of my 11.5" 6933 upper but shipping was delayed and I wont have it until Monday.

Very excited to see the gel tests.

If Federal keeps producing Mod 1 I'd bet more will trickle out but will they keep production going? I'm not sure what its place with the USMC will be now that the M855A1 was universally adopted. But then again I'd rather find a couple cases of M855A1 seconds than Mod 1 anyway

Bump with BlueFalcon's gel test results.

https://www.ar15.com/forums/general/Gel-Test-Mk318-Mod1/5-2146528/?r=-1&page=1&anc=74500439#i74500439

Nice, thanks.  I have been thinking about a few cases of this for "go-to" 11.5" ammo.  50 gr TSX Optimized is just so.....pricey for 5.56.

The original "brown box" Mk318 was rumored to be hotter, too bad it is now unobtanium.

I wish Mk318 was loaded to the same velocity as M855.

Im not sure why people are saying its better than Mod 0. To me it looks the same or even slightly worse since it doesnt seem to fragment as much. Not that all impressive compared to M855A1.

is it a hard fact that the Marine have adopted the 855a1?

if so, that might mean the end of the 318.

It's interesting, the MK318 is faster then M855 from a 11.5", but a good bit slower then M855 from a 16":

As far as I know it's the M855A1 going forward now. The Mk318 may be used for certain things but who knows, that's just my speculation (wishful thinking). I have a few hundred rounds of Mod 1 and Ill probably just sit on them now unless Federal keeps producing it.

I like the Mod 0 very much. I have it loaded in my ready mags.

It looks from the data that the Mod 1 is a little better (slightly faster and more consistent). I'm curious how the accuracy compares between them since poor accuracy is a criticism of the 318. I usually get about 2 to 2.5 MOA with my MK318 Mod0 with an occasional 4MOA group caused by a flier. Still more consistent than XM855.

I'm surprised we are still seeing any 318 especially the Mod0 since it was replaced by the Mod1 then everything replaced by the M855A1.

I can't find any Mod 0...

I've scored about 1500 Mod 1 projectiles off of gunbroker in the last few months. Been meaning to do some reloading and testing. Just never got around to it yet.

Federal still has a contract for Mod 1.  Complicated things going on in the politics of the rounds. Marine Corps want to keep the Mod 1 and haven’t been forced to switch to 855A1 so they haven’t. All I can let out at this time.

Federal has done many tests on the Mod O vs Mod 1. Mod 1 is better. Better BC, slightly hotter and consistent. Accuracy was improved.  I know this for a fact.  In the know.