Chrome lined vs chrome moly

[downzero]

. Ive also heard that the 1:9 twist is the best all around barrel for moving between different weighted bullets (55 grain-62 grain for me). Is this true?

I have also heard this but I didnt see a 1-9 on the site that had them for $170. Guess I have to sacrifice somewhere to get the price I want.[/QUOTE]

1 in 8 is the best compromise for 55-80 grain bullets, in my opinion.

 

[95wrangler]

Well thats even closer to the 1-7! How much difference can there be in a 16" barrel between a 1-7 and a 1-8? Like I said Im not shooting for sub moa!

 

[95wrangler]

I was just reading on Bravo Company USA that the 1-7 twist is acceptable for heavier bullet weights. Just their Im sure! The down side is that while I was there I found a complete Upper just like what I was going to build and probably cheaper than what I could build it for..... Damn! I kinda wanted a project but whos to argue with price!

 

[grizman]

Current USGI issue is 1:7 twist and they run bullet weights from 55grns to 77 grns thru the 1:7 with acceptable accuracy. Some 1:9s will shoot 62grn+ rounds OK some won't. Some 1:7s do poorly with lighter than 55grns. In reality the 1:7 twist is more flexible because it can handle all but the lightest bullets, where the 1:9s don't normally do well with the heavier/ longer bullets used in the newer more effective loads out there like the 77grn OTM loads etc.

Unless you are going to hunt squirrel with some 45grn varmint loads 1:9 may not be the best compromise.

 

[95wrangler]

No squirrel hunting here! Just plinking.

 

[Yeah]

Yeah im thinking im going to buy their 10/22 bull barrel and stock combo for $135. Looks like they have great prices but im not sure if thats any indication of their quality. I hadnt looked at their AR barrels but im definately interested in hearing anyones input on these. Ive also heard that the 1:9 twist is the best all around barrel for moving between different weighted bullets (55 grain-62 grain for me). Is this true?

Green Mountain's 10/22 barrels are excellent. I have a couple in 0.920" and a couple in sporter weight and they all shoot as well or better than like sized Shilens. Don't know about their AR wares.

1-7 will handle anything 1-9 will, though the reverse is not true. Neither is is true that 1-9 is more capable for 55s to 62s, nor that all bullets of equal weight are of equal length.

 

[DCM8513]

So it sounds like the 1:7 is the way to go for flexability between 55 grain and 62 grain? I will probably take my AR squirrel hunting once and a while just for practice. But wouldnt ever anticipate using lower than the 55 grain.

 

[DCM8513]

I just looked at the green mountain m4 16" barrel and it says that they are a production over run from a manufacturer (unknown) that was initialy made for a piston system AR but says they will work fine for a standard gas system. I think ill call tomorrow to see if i can find out the acutal manufacturer. Im wondering if this is a quality barrel. Arent the new ARs that are produced with a piston system typically higher end quality?

 

[Yeah]

Knowing the intended recipient isn't going to matter, as you know the manufacturer in Green Mountain. If you mean the $129 special on their page, it is 1-7", chrome lined, 4150 steel, M4A2 profile, and has an M4 extension.

The only other thing I'd want to know is the gas port size.

 

[DCM8513]

Knowing the intended recipient isn't going to matter, as you know the manufacturer in Green Mountain. If you mean the $129 special on their page, it is 1-7", chrome lined, 4150 steel, M4A2 profile, and has an M4 extension.

The only other thing I'd want to know is the gas port size.

So youre saying this would be something worth purchasing? What are the different diameter gas ports and what size do i want to be close to?

 

[downzero]

Well thats even closer to the 1-7! How much difference can there be in a 16" barrel between a 1-7 and a 1-8? Like I said Im not shooting for sub moa!

I have both 1 in 7 and 1 in 8; I tend to think that 1 in 8 is the best compromise because 1 in 8 is fast enough to shoot the 77 grain SMK, which is about the longest/heaviest bullet that is practical for a magazine-fed AR-15.

Given the choice between 1 in 7 and 1 in 9, I would pick 1 in 7 every time.

It's strange to me that 1 in 9 has become so popular when 1 in 8 stabilizes 75 and 77 grain bullets just fine and still works fine with the 55s for plinking.

 

[bowtie]

I have a Rock River upper 1-9 twist and my buddy has a Yankee Hill upper with a 1-7 twist. Using 62 gr m855 we havent seen a difference at our local 100 yd range. Im sure the 1-7 twist would be more accurate out to 400 yds and would do better with a heavier bullet.

Regardless I didnt know anything about twist rates prior to getting into the AR game

 

[Yeah]

So youre saying this would be something worth purchasing? What are the different diameter gas ports and what size do i want to be close to?

Gas port Sizes - M4Carbine.net Forums

I don't see anything about that barrel that would steer me away, if I wanted chromoly.