PDA

View Full Version : Can a novice change the barrel on an AR?


das
11-02-12, 10:50
I would like to maybe switch from a 1:9 twist barrel on my M4 to a 1:7 or 1:8. Can a novice change out the barrel or is it something too difficult for me to attempt? I am by no means a pro on the AR platform really just got started a few years ago. Thank you. Dom
PFran42
11-02-12, 10:55
With the proper tools, you can switch out a barrel in about 5 minutes (standard polymer hand guards). 10-15 minutes depending on what type of quad rail/tube/FF setup you are running.

All of the above assumes that the barrels in question have the same length gas system. Now if you are talking about removing gas blocks, installing new ones, pinning, etc. It can take a bit longer.

Here is a decent video for your reference:

http://www.youtube.com/watch?v=UCxa0JJU4Iw
markm
11-02-12, 10:59
How are you limited by your 1/9?

I ask this to make sure you aren't just swapping based on internut gibberish.... I say this because we are getting good results with 77 gr SMKs in a rem 700 5R bolt gun that has a 1/9 twist.
das
11-02-12, 11:00
No I would stick with the same length same profile barrel just different twist. I have MOE hand guards on the one that would get the change so that wouldn't be an issue. Thank you. Dom
PFran42
11-02-12, 11:03
No I would stick with the same length same profile barrel just different twist. I have MOE hand guards on the one that would get the change so that wouldn't be an issue. Thank you. Dom

What you describe, would take no longer than 5-10 minutes (with the proper tools). If you are shooting primarily 55gr rds (which are the least costly and most readily available), I would personally stick with a 1:9 barrel.
das
11-02-12, 11:05
How are you limited by your 1/9?

I ask this to make sure you aren't just swapping based on internut gibberish.... I say this because we are getting good results with 77 gr SMKs in a rem 700 5R bolt gun that has a 1/9 twist.

You know you make a good point. I have stuck strictly with 55 grain ammo because of the 1:9 twist. It would be foolish of me not to see how well it stabilizes a heavier grain first. Thank you.
markm
11-02-12, 11:14
Yeah... give it a try. I know you'll get good results with 69 gr. Maybe even 77s too. We're even running 77s thru a silencer on that 1/9 barrel.... so that's saying something.
mizer67
11-02-12, 17:10
Yeah... give it a try. I know you'll get good results with 69 gr. Maybe even 77s too. We're even running 77s thru a silencer on that 1/9 barrel.... so that's saying something.

How long is the barrel on that Rem 700? They're usually longer than carbine length and that should help stabilize the 77 gr SMKs.

1/9's are luck of the draw with 16" barrels. I don't really care though, most of my shooting is <300 yards and I love the 69 gr SMK for those distances; it stabilizes in most anything.
MistWolf
11-02-12, 23:52
The extra length of the barrel does not stabilize the bullets better. The extra length usually means more velocity which means more RPMs and it's the RPMs, how fast it's spinning, that stabilizes a bullet

Yes, you should see how your current barrel handles the longer bullets. It may shoot just fine
Texas42
11-03-12, 06:28
The extra length of the barrel does not stabilize the bullets better. The extra length usually means more velocity which means more RPMs and it's the RPMs, how fast it's spinning, that stabilizes a bullet

Yes, you should see how your current barrel handles the longer bullets. It may shoot just fine


More barrel = more velocity = more RPM's = longer bullets can be stabilized.

Therefore: longer barrel can stablilize longer bullets with the same twist rate. Correct?
das
11-03-12, 07:20
Thank you everyone. I will try the heavier, longer bullets first. 16" barrel on both M4's we will see how the one that is 1:7 differs from the 1:9. Will post as soon has I can with results from mine. Dom
wahoo95
11-03-12, 09:05
Some 1/9 barrels shoot 77gr ammo just fine because they are really closer to 1/8. Others really suck with 77gr ammo and maybe even 75gr ammo because they are closer to 1/10.

I would say keep the 1/9 unless you honestly have plenty of 77gr ammo to shoot.
jesuvuah
11-03-12, 10:03
Swapping barrels is farily simple especially if the gas block is already attached to the new barrel. I agree though that I would give the 1/9 a chance.
das
11-04-12, 01:18
69's work fine in both of them. I guess I will just leave well enough alone at this point, especially since I stick with 55's almost all the time. Thank you everyone. Dom