5.56 Barrel Question

[chavez_e_chavez]

Barrel marked ST-MIL-B-11595E-CMV .I know its a Nato 5.56 with 1/7 twist but its it a heavy barrel or standard ?? cheers

[SomeOtherGuy]

"ST-MIL-B-11595E-CMV"

ST most likely means Spike's Tactical (a brand).

Mil-B 11595E is a specific requirement for a type of ordnance steel. There are three slightly different steels that satisfy this requirement. Look on the sticky for the M4 "Chart" and follow the links for more info.

CMV means chrome-moly vanadium. Along with the 11595E it should indicate that the steel is the third of the three types of steels that meet 11595E and generally the most desirable.

I've seen this marked on a Spike's Tactical barrel sold with their "Elite" cold hammer forged uppers, which also had FN among the markings. Is that where you found this? That particular barrel was an intermediate profile that Spike's called "optimum" and is roughly equivalent to a govt profile under the handguards and in between govt and lightweight profiles - I think around 0.675" - forward of the FSB. There's a photo I've seen on here comparing that and many other profiles, but I don't have it ready at hand.

[chavez_e_chavez]

yep on my spikes upper.......ive searched the web and haven't got that answer..heavy or Std.. trying to sell and the potential buyer wants to know..

[Scorpion]

If it is a heavy barrel profile, it will be thicker under the handguards.

Govt-profile barrels are thinner under the handguards and thicker past the FSB. E-slap me if I'm wrong.