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If Alex is gonna make a special run of barrels for the 556, what twist do we REALLY want

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Discussion Starter · #1 ·
They apparently have not started making these yet. I think most informed folk would prefer the 1-8, as it can still allow for the lighter bullets like the 55gr M193 stuff and even some decent 50gr stuff.

I've always thought the 1-8 was Ideal for civilians (we dont shoot tracers enough to need the 1-7, which was probably a bit much even for tracers) but the market tends to follow the military and 1-7 is all that is offered.

Frankly it's my thought that since we are running a rifle that has been optimized for performance and innovates in many other ways, lets get this right by going with the 1-8 twist!! 8)

If you do vote, plan on voting with your wallet too. this should reflect an intention to purchase if it is offered. and dont worry about the length or profile on this poll, they will probably produce the same things they already offer.
 

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I want a faster twist for the 75gr+ weights. When 1:7 was brought up as imminent I jumped on it because it would do what I needed it to do. If 1:8 is the "new 1:7" then I'll go with it. It'll do what I need it to, I voted 1:8, but if the new barrels come out as 1:7, I wouldn't be butt hurt about it.
 

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Kreiger seem to go with 1:7.7 for 75 and 77 grain tips. Specifically the SMK 77 g Match king. so a 1:8 would be close enough. Ultimately though I'd be happy with either as I could shoot 55/62 with my 1:9 and switch out for 75/77 tips. If Alex wants military contracts he may be better off doing 1:7.
 

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1:8" would probably work out best for most. I am pretty sure that would work fine as an SBR barrel with a can on the end.


With all of that said, I still think 1:9" works for the majority of people.
 

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Since I have 1:9 twist. I see no need for a 1:8, but a 1:7 would be better for the 75-77 grain stuff.
 

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I shot matches with an AR in 1:8 and printed sub MOA (when the moon and stars were in balance of course!) with Sierra 77's. The 1:9's are right at that threshold of instability for a 75gr, hence why some barrels will shoot them well and some won't.

Now if you have intentions of using the XCR for some kind of slow fire matches where 80gr+ slugs will be used then that'll be a different story. But unless you're just farting around and not shooting for points or place there aren't many matches outside of club level that would allow the rifle.

Maybe debate this one; NATO or 223 Wylde chamber? NATO is what it is and works swimmingly for everyone regardless of what it is fed. The Wylde chamber can still take a NATO load but it has a shorter throat so less bullet jump for better accuracy.

I still remain on the stance that I'll take whatever comes out, be it 1:7 or 1:8.
 
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Discussion Starter · #11 ·
yeah, the 1-8 will 100% stabilize any bullet you can fit in the XCR. frankly the 1-9 stabilizes the 75gr hornadys i run thru it just fine at 100 yards, but I want it to be capable out to longer ranges, which is where the 1-8 comes in.

the 1-7 just over-stabilizes the 55 grain and lower stuff and you end up either blowing the bullet up, or getting crappy accuracy and higher pressures.
 

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The custom AR rifles for DCM Highpower matches are built generally with 1 in 8". I have a match gun with a 1 in 8" built by Compass Lake using a Douglas barrel blank. It shoots well with both 77 and 80 grain Sierra Match Kings. I have a factory Rock River with a 1 in 8" that will put 10 shots into 1 1/16" using 77 grain Sierra Match King handloads. The 1 in 8 twist will still shoot 50 to 55 grain ammo very well and will still be in the 1 moa range. I haven't seen a 1 in 7" twist barrel that would shoot 55 grain bullets well.

I've used that Rock River 1 in 8" twist to shoot metallic silhouette chickens out to 900 yards using the 77 grain SMK load. I couldn't hit anything at a 1000 yards because the bullets appeared to become unstable. I expect they dropped into subsonic just beyond 900 yard.

I've had numerous ARs with 1 in 12, 1 in 7, and 1 in 9 inch twists. I do not understand why the industry is so enamored with 1 in 9" twist barrels. I've never had one that shot very well with any load. That statement includes barrels from Robinson, Rock River, and Bushmaster. I tried to make 1 in 9" twist barrels shoot well with heavy bullets, but the ones I've had wouldn't shoot anything over 60 grains; most of this effort was with a Bushmaster Varmint rifle. It just wouldn't do it. The heavy bullets would group well at 50 yards but were unstable at 100 to the point they would completely miss the target.

The point is that the 1 in 8" twist is by far the most useful that I have seen. It will do anything and do it well. That is why the match shooters use them.
 

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Wolf Gold/Privi has a newer 75 Gr OTM that's designed specifically for 1/9 twist. I will find out if it works for me.
 

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Hornady 75g A-MAX is also supposed to work well in a 1:9 but a 1:8 would be great.
 
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Discussion Starter · #15 ·
well it looks like we want the 1-8 twist by a margin of 3-1!!

Terra, Is this something that we can make happen?
 
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