What guns used a 20" barrel?

[SoDak]

Now that I have a spare 20" A1 profile barrel, I'm trying to decide what kind of build I want. I'm not sure I want to do another M16A1 build since I have one already, so I'm looking at doing some other retro type build. The problem is I can't think of what other guns used a 20" A1 barrel other than the Colt 711. Does anybody know what other rifles used this barrel?

[kmrtnsn]

Deleted

[usafmsgtret]

I would suggest a visit to www.RetroBlackRifle.com. They have a wealth of correct information.

[Coleslaw]

Sorry dude, but you're a bit mistaken; the A1 was an 18" the A2 was 20".

?????

[Army Chief]

The M-16A1 (603) had a 20" barrel, as did the original M-16/AR-15.

AC

[kmrtnsn]

My mistake. I seem to recall the A1 being 18 point something and 20 with the flash hider attached and then being a full 20 after the A2 was released, I'll blame it on old age and a decent Cabernet.

[Army Chief]

I'll blame it on old age and a decent Cabernet.

A nod of respect for your greater life experience and impeccably good taste, sir. =]

AC

[.45fmjoe]

What guns used a 20" barrel? Well, Colt's model 601, 602, 603, 604 ...

The original Armalite AR-15 was a 20" barrel but in 1-14 twist. The early Colt 601 rifles were 1-14 twist, which later changed to 1-12. The barrel remained unchanged except for chrome linings, markings and small differences in front sight bases until 1983 when the M16A1E1 was officially adopted as the M16A2.

[SoDak]

What guns used a 20" barrel? Well, Colt's model 601, 602, 603, 604 ...

The original Armalite AR-15 was a 20" barrel but in 1-14 twist. The early Colt 601 rifles were 1-14 twist, which later changed to 1-12. The barrel remained unchanged except for chrome linings, markings and small differences in front sight bases until 1983 when the M16A1E1 was officially adopted as the M16A2.

Thanks for the info. I have given thought to something like a 604, but since it wouldn't be much different than my 603, I was looking for something different. Did any of the Canadian C7 rifles use an A1 barrel or were they all A2 barrels?

[.45fmjoe]

Thanks for the info. I have given thought to something like a 604, but since it wouldn't be much different than my 603, I was looking for something different. Did any of the Canadian C7 rifles use an A1 barrel or were they all A2 barrels?

According to Black Rifle II the C7 rifles shared the same controversial barrel profile as the M16A2.