Ar build 16" vs 18" barrel

[jay.sharkbait]

I find these threads fascinating

[carpsniperg2]

1:8 and a 18" barrel is my favorite in a 5.56.

[WoodlandShooter]

some food for thought...IMO, it more of a personal preference regarding the difference between a 16 and a 18....they are both good for shooting R.A.T.s

[mountainman]

I find these threads fascinating

Always gets entertaining!

[WoodlandShooter]

Hardly any difference. If you want to do it right, go 18" with a rifle length gas system, 13.5" or longer handguard. It's a 18" with the performance of a twenty. How wrong can the MK12 be. 

Can't wait for the "Google Foo" types to get all spun up on a rifle length 18".

LOL, my father in law picked a MK12 barrel...had no clue what he had...said it would short stroke "slightly" and not lock back the BCG after the last round...anywho, I told him to run heavier loads that the 50 grain 223 stuff.

[Heredoggydoggy]

Hardly any difference. If you want to do it right, go 18" with a rifle length gas system, 13.5" or longer handguard. It's a 18" with the performance of a twenty. How wrong can the MK12 be. 

Can't wait for the "Google Foo" types to get all spun up on a rifle length 18".

LOL, my father in law picked a MK12 barrel...had no clue what he had...said it would short stroke "slightly" and not lock back the BCG after the last round...anywho, I told him to run heavier loads that the 50 grain 223 stuff.

Also, tell him to look at the gas rings on the bolt and make sure the gaps in the rings are alternated on the bolt.  I've shot 50 grain bullets in my AR, and they function fine.  Admittedly, they were handloads, but even at the bottom of the load range, they still functioned... 

[WoodlandShooter]

will do!!!

Iam just itchin to get my recce all put together...should have the remainig parts next week.

[ML_Hunter]

I'm not going to say much that everyone else hasn't said, but its going to come down to what you want. I built an 18" rifle for myself and a 16" for my old lady. As I shoot them, they are so close to the same and you really wont be able to tell at all the difference in how thy shoot. I do prefer a mid length gas system and the longer fore end. The 1/7" twist is a nice when you start shooting your 72+ grain bullets, but if your only shooting 55 or 62 grain bullets, all of the barrel twist rates will work just fine.

Have fun with the build , its quite fun and I'm sure after your first, you will be looking for an excuse to build more AR's 

[Bmcox86]

I went and checked some guns out today, decided to go with 18" barrel and 15" rail. The twist will be 1:7 and its a rainier arms mountain series.

[CastleRocker]

I went and checked some guns out today, decided to go with 18" barrel and 15" rail. The twist will be 1:7 and its a rainier arms mountain series.

Great choices.  The only AR's I've had that were pretty much the same (for comparisons sake), were the three R-15's I had.  The only difference between them were the barrel lengths.  I had a 16", and 18" and a 20".  The 16" is LOUD compared to the other two.  Other than the noise and the weight, I could never find a difference worth discussing.   

Still have the 16" and the 18".  Got into other caliber AR's and had to part with the 20". 

In my opinion, a flash hider/muzzle break is NOT a necessity, especially on a 223 or smaller, and will only help to destroy your hearing.  My DTech in 25 WSSM is my only upper with one, and the ports are very small, so it's not obnoxiously loud. 

[Biggerhammer]

I went and checked some guns out today, decided to go with 18" barrel and 15" rail. The twist will be 1:7 and its a rainier arms mountain series.

Well done, great choice.

[Craig]

18" barrel with 16.7" Noveske NSR rail. Great combo.