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tpelle
23 February 2012, 11:37
At what point did the military switch from lightweight profile barrels to the "government" profile. Was it when they went from the M16A1 to the M16A2? Were M16A2 rifles ever built with lightweight profile barrels?

5pins
23 February 2012, 11:55
Yes, when they went to the A2s and no the A2s never had the thinner barrel.

Casull
23 February 2012, 16:34
I also have a question..

Why were the barrel profiles changed, and what was the idea behind the designs? Some have pointed out the government profile barrel is very odd.

5pins
23 February 2012, 17:47
It is my understanding that the A2 barrel was thickened at the FSB forward to reduce bent barrels. Every A1 bent barrel I have seen was bent in front of the FSB.

Casull
24 February 2012, 03:02
One more question: Would that mean free-floating a government profile barrel takes away from its durability as opposed to a more consistent profile?

tpelle
24 February 2012, 06:09
It is my understanding that the A2 barrel was thickened at the FSB forward to reduce bent barrels. Every A1 bent barrel I have seen was bent in front of the FSB.

I knew the barrel was made heavier ahead of the FSB, and the reason was that, in Vietnam, the soldiers would use the rifles with bayonet attached as a pry bar to open crates. Also the older style flashider, with the open ends, were used to break the strapping on crates by sticking the flashider over the strapping and twisting. Not conducive to accuracy.

I just wasn't sure when the change actually took place.

I do not think there would be any ill effect to free-floating a Government Profile barrel. It would seem to me that a GP barrel would actually benefit more from free-floating than would, say, an HBAR, as any pressure transmitted to the barrel through the handguard, such as from resting the handguard on something or from a sling-supported position, would have no effect. Use with a bayonet, from a purely hypothetical perspective (as bayonet use doesn't figure large in civilian use of a rifle), would probably not be advised, however, as barrel support from the handguard would seem to be important in that application.

markm
24 February 2012, 09:52
One more question: Would that mean free-floating a government profile barrel takes away from its durability as opposed to a more consistent profile?

No.

Quib
24 February 2012, 10:15
I have an article from around 1982 that introduces the A2 and covers some of the design changes.

When I get home from the office tonight I'll see if I can dig it up.

Casull
7 March 2012, 03:17
Don't mean to intrude but have you had any luck finding it? [:D]

tpelle
7 March 2012, 13:13
No, I haven't. It appears that all 20" barrels are manufactured from unobtanium! Scarce as hen's teeth!

I ended up ordering a kit from J&T Distributing - a 20" A3 configuration with a 1-9 twist non-chrome-lined HBAR barrel. I know a 1-9 barrel will stabilize pretty much any ammo I'll ever shoot - I started shooting Highpower Rifle with a 1-9 twist Wilson barrel shooting 69 grain Sierra Match Kings, and it was more accurate than I was. I only upgraded my competition rifle to a White Oak 1-7 twist so I could shoot 80 grain Match Kings for the medium range (600 yard) stages.

Because J&T is in Kentucky, and since I live in Kentucky as well, I had to pony up almost $37.00 in sales tax! Bit it so happens that I have a private sale DoubleStar lower to put this kit on, and J&T and DoubleStar are the same company, so at least I'll have an all-DoubleStar rifle when I'm done.

Supposed to have it in 2 to 3 weeks (unless the lady I talked to on the phone was blowing smoke).