What does "government profile" mean to you?

[Junkie]

I just got an upper that came with a barrel advertised as 16" midlength government profile.

To me, government profile means it gets bigger in front of the gas block, which I don't like. I bought the upper anyway because I wanted it and the handguard.

Well, while I haven't pulled the handguard off and taken a caliper to it, it appears to me that the barrel is pretty much a constant taper interrupted only by the gas block. It appears smaller in front of the gas block seat than behind it. While I'm happy with this, it certainly isn't what I expected.

Is my definition of government profile wrong, or is the description wrong?

[echoThreeOneSix]

here's a thread at arf...

http://www.ar15.com/forums/t_3_12/573125_.html

[coy80176]

I wasn't sure until this one

http://www.calguns.net/calgunforum/showthread.php?t=980928&highlight=Government

[Junkie]

I decided to pull off the handguard and take a look.

Just in front of the initial taper it's .798". It tapers from that to .715" just behind the gas block. Just in front of the gas block it's .675", then it tapers down to .625" before it flares up to .718" to give a proper mating surface for a muzzle device.

It's an Aero Precision, the upper is their M4E1 which has built in mounts for their handguards, came with a 15" Keymod handguard for $350 total. Seeing as the barrel seems pretty nice and is a reasonable profile, I may keep it and see how it shoots rather than immediately pulling it and throwing an SPR barrel on.

[CenCalHobbist]

That sounds like a much preferred profile than the "government" profile.

[Junkie]

Yep, I agree. I'm emailing them just to give them a heads up, as there may be some people who prefer government profile for some reason.



That's what I received (handguard was on, I pulled it to measure)

[Anthracis]

***

[Junkie]

I don't think this barrel is particularly lightweight. I wouldn't be surprised if it weighs a couple ounces more than an M4 profile. Aero claims on their web site that their 16" midlength government barrel weighs 32oz, while Ballistic Advantage claims theirs weighs 28oz. Looking at and feeling this barrel, I wouldn't be surprised at all if it weighs 32oz.

[gemini1]

Not an expert, but those measurements does sound more like lightweight instead of govt profile?
I have a 16" middy. BCM classified it as standard, but on their description, it mentioned govt profile. I dont have the measurement under the handguard, but Im guessing its under .700. FSB is .725, beyond is .740 and about half an inch before the muzzle, its .720

[david_place_834]

Actually, I am looking into purchasing that exact some item from Aero. $350 for a QPQ barrel 1:8, monolithic keymod, reinforced upper. A STEAL! I'll be calling Aero to see if they can cerakote Burnt Bronze to match the same their lower.


Shoot it and give a review!

[Junkie]

gemini1, I'd call it more of a medium profile barrel than a lightweight barrel. To me, lightweight means similar to government behind the gas block, and then no fatter than that (and maybe skinnier) in front.

david, I agree that it's a steal. Not sure why you call the upper reinforced, though, I think it's a pretty typical billet upper other than the handguard mount.

[ferocious]

"Goverment Profile" = the government's secret records they keep on you. : )

[ar15barrels]

I just got an upper that came with a barrel advertised as 16" midlength government profile.



To me, government profile means it gets bigger in front of the gas block, which I don't like. I bought the upper anyway because I wanted it and the handguard.

Proper Govt contour barrels will taper from 0.670" just froward of the big step in front of the barrel extension down to 0.600" behind the radius up to the step behind the gas block seat.
That's the only dimension shared across M16A1-2-3-4 and M4 barrels.
M4A1 does not follow that standard.

[Junkie]

I don't see dimensions on the M4A1 profile, is this more similar to it?

[ar15barrels]

I don't see dimensions on the M4A1 profile, is this more similar to it?

M4A1 is like an SPR.
0.840" straight under the handguards.