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Posted: 5/19/2009 6:07:44 AM EDT
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Hello all, i've browsed these forums for a long time but had a question to ask.
I'm looking at putting together my own black rifle, and i've been able to find pretty good information about uppers, lowers, and most other parts that I'm going to need, but when I set out to find a good barrel, I had no idea where to turn. Then I realized that I know almost nothing about barrels in the first place. Does increased length mean better accuracy? what materials are best? (I hear chrome plated is the way to go) Who are the big names in the barrel industry? does any barrel fit any upper? If anyone could give me some information on barrels it would be GREATLY appreciated. thanks for reading! |
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I was in a similar situation as you a couple of months back; and I’m no expert by any means but here is some useful info I picked up while I was searching for a stainless 16” CAR with fluting.
Any AR15 barrel should fit any AR15 upper; given the gas system matches what want to use; CAR or Middy aka full length You can get barrels in different profiles, Lt Weight, std, Hbar (Heavy .750 dia) , etc. this is important if you’re going to change the FSB since the dia are different for each profile. Longer barrel length = greater accuracy, just a general rule. 7 twist (riffling) is better for heavier weight bullets i.e. 77gr, makes them more stable with the faster rate of spin 8 twist, kind of an all purpose riffling, not the best for any one weight bullet. 9 twist, best for 55gr bullet’s, but this doesn’t mean you can’t shoot 77’s it’s just that the 77’s won’t be as stable in long flight situations, and it’s not the “optimal” twist for a heavy bullet. Chrome lining of the barrel helps in wear; a properly maintained CL barrel should last longer than a similarly maintained Chrome-moly one. I think most would agree Stainless is the best material, but it’s pricey, and some say a pain to maintain properly. And there is nothing wrong with a CM (Chrome-moly) either. I think all the ARFCOMM mfg can get you a “good” quality barrel. If you’re looking for a tac-driver (match) type barrel, try reading the info for Krieger, Douglas, Lilja and ER Shaw. I would consider these to be “Premium” type barrels; they have more stringent requirements for their blanks than most others, no internal tooling marks, hand lapping, air Gauging, etc. Lilja Stainless steel barrels are guaranteed to be uniform to .0001" these types of barrels usually run $75-$150 more than the normal barrels. My best advice is do some research on the web and call some of the places I mentioned, and talk to them. BTW; I ended up ordering a Douglas, because of price and availability, but I would have preferred a Krieger |
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No, barrel length does not equal greater accuracy.
Mechanically it is more difficult to make a long barrel accurate. Short barrels are more rigid by virtue of having greater thickness to length ratio. To make a long barrel as rigid it need to be heavier. To get the bore perfectly centered and straight for the longer distance is harder. To maintain bore diameter is also more difficult. Long accurate barrels are expensive for a reason. Now when it comes to velocity then a longer barrel will generally give you greater velocity. This can be an aid to placing your shots over a greater range because the projectile is moving faster and is influenced less by wind and external factors. trajectory is also flater so less drop calculation is required. If you're shooting really long range then you need to worry about how far teh bullet will travel before dropping back below the sound barrier, which is disruptive to the bullets path and poor for precision shots at long range. Another factor where a long barrel can help you with accuracy is if you are using iron sights. A longer sight radius (distance between front and rear sight) allows for better precision alignment of the sights when shooting. Ive seen 14.5" Noveske barrels shoot 100yd cloverleafs with good ammo. The bullet will have more of a rainbow arc though at 800yds than if the round was fired from a 24" barrel due to velocity loss. You live in Oregon so Noveske should ring a bell. They make fantastic barrels. Barrel choice has a lot to do withthe intended application of the rifle. A 24" bull barrel may be desireable if you are shooting at prarie dogs at 300 yards and need to see an impact, because the weight of he barrel helps keep the rifle steady from recoild so you can confirm hits. Also prarie dog shooting is often done from a portable bench where you don't care if the rifle weighs 13 lbs. If you intend to shoot run and gun type games you may want a short lightweight barrel that swings from target to target fairly fast, and the long shots aren't as important. Maybe you want a "walk around coyote slaying carbine" that is light enough to carry from calling stand to calling stand all day, but is accurate and steady enough to hit a six inch vital zone at 250-300 yds. An HBAR profiled 16" carbine with a low powered optic would provide you with a light, accurate and powerful enough package to make the hits without tiring you out to bad. |
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thanks a lot to both of you, first off.
and yes i am familiar with noveske 
i looked around and i was interested by sabre defense's competition barrels... any word on that? or just a general sabre defense review i think i want to stick with 16"-18" if possible i'm also going to look into lilja and kreiger, douglas, etc. thanks again! (any further information is still appreciated) also, how do you tell what kind of gas system you are using? |
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Quoted:
No, barrel length does not equal greater accuracy. Mechanically it is more difficult to make a long barrel accurate. Short barrels are more rigid by virtue of having greater thickness to length ratio. To make a long barrel as rigid it need to be heavier. To get the bore perfectly centered and straight for the longer distance is harder. To maintain bore diameter is also more difficult. Long accurate barrels are expensive for a reason. Now when it comes to velocity then a longer barrel will generally give you greater velocity. This can be an aid to placing your shots over a greater range because the projectile is moving faster and is influenced less by wind and external factors. trajectory is also flater so less drop calculation is required. If you're shooting really long range then you need to worry about how far teh bullet will travel before dropping back below the sound barrier, which is disruptive to the bullets path and poor for precision shots at long range. Another factor where a long barrel can help you with accuracy is if you are using iron sights. A longer sight radius (distance between front and rear sight) allows for better precision alignment of the sights when shooting. Ive seen 14.5" Noveske barrels shoot 100yd cloverleafs with good ammo. The bullet will have more of a rainbow arc though at 800yds than if the round was fired from a 24" barrel due to velocity loss. You live in Oregon so Noveske should ring a bell. They make fantastic barrels. Barrel choice has a lot to do withthe intended application of the rifle. A 24" bull barrel may be desireable if you are shooting at prarie dogs at 300 yards and need to see an impact, because the weight of he barrel helps keep the rifle steady from recoild so you can confirm hits. Also prarie dog shooting is often done from a portable bench where you don't care if the rifle weighs 13 lbs. If you intend to shoot run and gun type games you may want a short lightweight barrel that swings from target to target fairly fast, and the long shots aren't as important. Maybe you want a "walk around coyote slaying carbine" that is light enough to carry from calling stand to calling stand all day, but is accurate and steady enough to hit a six inch vital zone at 250-300 yds. An HBAR profiled 16" carbine with a low powered optic would provide you with a light, accurate and powerful enough package to make the hits without tiring you out to bad. I could be wrong; and may possibly be, but doesn’t the added barrel length aid in stabilizing the bullet during flight and also provide a more flat trajectory, giving more accuracy? I was told the longer the projectile remains in a constant line and on rifling the arc will be flatter, and because of the additional time on rifling the projectile will actually achieve a better centered rotation. The example I was told; a projectile coming out of a 20” barrel will remain on a constant centerline for almost double the time the same projectile coming out of an 11.5” barrel. This means the projectile actually gains rotational momentum as it’s traveling the extra 8.5” instead of slowing down the rotation when it hits the outside air where there is nothing to keep the projectile spinning. For example a compact 9mm is less accurate than say a long slide target pistol with the same rate of twist. Like I said I may be wrongly informed, but this is pretty much the same thing I heard from all the mfg I talked to, and it seemed to make sense at the time.. nm, Lilja straightened me out; your right, stiffer barrel, more accurate |
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