Colt AR advice needed

[Mld3021]

AR novice. Only owned Bushmaster. Have the new gun bug Stuck between a 6920 and a 6940. Accuracy critical. Don't mind price difference. Help? Thanks.

[Reservoir Dog]

If accuracy is you primary concern, then the 6940 would have a slight advantage out of the box because of the free-float barrel (due to the design of the monolithic upper).

That being said, I am not sure that the slight accuracy increase justifies the higher price and lack of versatility of the 6940. The 6920 could be made to do everything the 6940 can, with the added ability to change out rail platforms (if you ever wanted).

[Mld3021]

Dog, thanks. How important is it to change out rails? I will never hang a laser, light, etc.

I want the better rifle. And I like the idea that the 6940 is being discontinued. And it looks really cool.

But, I don't know what I'm doing and that is why I need help.

[Reservoir Dog]

How important is it to change out rails? I will never hang a laser, light, etc.

I like to have the ability to change out rails. Maybe I want to go a different route with my rifle, or I find a rail system I like better than what I have. There are various reasons. With the 6920 you have that ability. With the 6940, you are stuck with what you got.

However, if you don't plan on using the rail system, then why spend the extra $300 or so on the 6940? Buy extra mags and ammo!

[Mld3021]

I like the flip up front sight on the 6940 If I change the rails on the 6920, what about the front sight?

[Johnny Rotten]

I have both, LE6920 and a LE6940, I prefer the 6940 because I use a aimpoint with a maganifer, both using std QD larue mounts and BUIS, that's going to be a little diffuct on the 6920 with the above set up (edit: I just received a MI drop in rail today, so I might be full of chit), personally I don't like looking through optics and seeing to front sight of the 6920...

BTW: both guns are not being discontinued, there called SP6920/40, unless your a colt collector and you luv roll marks, they'll work exactly the same..

[alwaysonjohn]

Q: What about the front sight (referring to the 6920)

A: If you get quad rails and you want to use flip-up sights instead of the stock front sight then you can have someone like adco file down the front sight so it becomes a low profile gas block and will fit under any quad rail. Most shops charge $40 to do this and you can do it yourself using guides on the internet if you really want to be cheap. Or you could buy a new low profile gas block, but the stock sanded down should work fine and some folks claim it works better than any aftermarket low profile gas block!

[Guest BungieCord]

If accuracy is your primary concern, you'll want to get a barrel chambered in either .223 Remington or .223 Wylde, not in 5.56 NATO. All OE Colts and Bushys have a 5.56 chamber.

The NATO chamber is a little 'looser' in the interest of maintaining reliable feeding when the chamber is grungy. The Wylde was developed as a match grade chamber with a longer leade than the .223 Rem so competitive shooters could use bullet weights that otherwise would have been too long. The Wylde also is rated for NATO chamber pressures, which is about 5000 psi higher than the .223 Rem.