What would be more accurate in the bull barrel. A 16inch or 18inch or would I even notice a differance between the two?
And what would be better 1/8 twist or 1/9
And what would be better 1/8 twist or 1/9
Building an AR-15 have a barrel question.
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Re: Building an AR-15 have a barrel question.
Barrel length does not determine accuracy. The only difference you will notice is the weight, essentially. The velocity difference of 2 inches is inconsequential.
Accuracy is determined by :
1) the degree of concentricity of the bore within the barrel, and the consistency of the bore diameter. Production-grade barrels often have slightly tight spots you can feel when you drop a pin gauge down them, while match barrels are more straight and perfectly cylindrical along their bore.
2) the Crown
3) the rifling design and profile
ETA: while a heavier barrel is often more resilient and resistant to changes in harmonics due to heating, a poorly made "bull" barrel may be less accurate than a well-made light weight barrel.
Barrel length does not determine accuracy. The only difference you will notice is the weight, essentially. The velocity difference of 2 inches is inconsequential.
Accuracy is determined by :
1) the degree of concentricity of the bore within the barrel, and the consistency of the bore diameter. Production-grade barrels often have slightly tight spots you can feel when you drop a pin gauge down them, while match barrels are more straight and perfectly cylindrical along their bore.
2) the Crown
3) the rifling design and profile
ETA: while a heavier barrel is often more resilient and resistant to changes in harmonics due to heating, a poorly made "bull" barrel may be less accurate than a well-made light weight barrel.
Re: Building an AR-15 have a barrel question.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 308longshot</div><div class="ubbcode-body">What would be more accurate in the bull barrel. A 16inch or 18inch or would I even notice a differance between the two?
And what would be better 1/8 twist or 1/9 </div></div>
The 18 incher will display a little faster velocity all the time, noot much but some. For the shorter distance, say anything under 200 yards, you won't see any difference. The only thing the slightly higher velocity would show is a little less time in flight with the attendant slight, but the difference will be minimal, maybe 50FPS.
As for the twist, it depends on what you intend to shoot out of the rifle. The 1:8 will let you shoot 77gr and 80grain bullets with little problem; the 1:9 may have difficulty stabilizing anything longer than the 69gr bullet. The 75 HPBT way work in there.
So a good question to answer is what are you planning on doing with the rifle?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 308longshot</div><div class="ubbcode-body">What would be more accurate in the bull barrel. A 16inch or 18inch or would I even notice a differance between the two?
And what would be better 1/8 twist or 1/9 </div></div>
The 18 incher will display a little faster velocity all the time, noot much but some. For the shorter distance, say anything under 200 yards, you won't see any difference. The only thing the slightly higher velocity would show is a little less time in flight with the attendant slight, but the difference will be minimal, maybe 50FPS.
As for the twist, it depends on what you intend to shoot out of the rifle. The 1:8 will let you shoot 77gr and 80grain bullets with little problem; the 1:9 may have difficulty stabilizing anything longer than the 69gr bullet. The 75 HPBT way work in there.
So a good question to answer is what are you planning on doing with the rifle?
Re: Building an AR-15 have a barrel question.
The gun will be used mostly for target shooting and some varmit hunting.
The gun will be used mostly for target shooting and some varmit hunting.
Re: Building an AR-15 have a barrel question.
For hunting, I think a 20" or longer barrel is much better. The little 223 cartridge needs all the help it can get when shooting at long range (500+). A longer barrel does not improve accuracy, it improves muzzle velocity, which improves long range ballistics and effectiveness. STick with a 1:8 twist for up to 75 grain bullets. You may even want to get a 1:7 twist for 80-90 gr bullets....just depends on what weight you will be shooting.
Other reasons I like a longer barrel: the bolt cycles more softly, a little less noise and muzzle flash.
For hunting, I think a 20" or longer barrel is much better. The little 223 cartridge needs all the help it can get when shooting at long range (500+). A longer barrel does not improve accuracy, it improves muzzle velocity, which improves long range ballistics and effectiveness. STick with a 1:8 twist for up to 75 grain bullets. You may even want to get a 1:7 twist for 80-90 gr bullets....just depends on what weight you will be shooting.
Other reasons I like a longer barrel: the bolt cycles more softly, a little less noise and muzzle flash.
Re: Building an AR-15 have a barrel question.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 308longshot</div><div class="ubbcode-body">The gun will be used mostly for target shooting and some varmit hunting. </div></div>
Well, for either tasks, a longer barrel is better because it will generate a higher MV which will improve your accuracy in windy conditions. Trust me on this, when the wind blows, you want to get on target quickly, even if you are the world's greatest wind reader.
I would suggest a stainless steel 20 or even 24inch 1:8 barrel, which will enable you to shoot anything up to and including 80-82 grain bullets with no problems. With that kind of setup you will be able to get to 600yards and beyond, especially if you handload.
I just saw where Remington is now offering 77gr SMK factory ammo.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 308longshot</div><div class="ubbcode-body">The gun will be used mostly for target shooting and some varmit hunting. </div></div>
Well, for either tasks, a longer barrel is better because it will generate a higher MV which will improve your accuracy in windy conditions. Trust me on this, when the wind blows, you want to get on target quickly, even if you are the world's greatest wind reader.
I would suggest a stainless steel 20 or even 24inch 1:8 barrel, which will enable you to shoot anything up to and including 80-82 grain bullets with no problems. With that kind of setup you will be able to get to 600yards and beyond, especially if you handload.
I just saw where Remington is now offering 77gr SMK factory ammo.
Re: Building an AR-15 have a barrel question.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sig685</div><div class="ubbcode-body">
I would suggest a stainless steel 20 or even 24inch 1:8 barrel, which will enable you to shoot anything up to and including 80-82 grain bullets with no problems. With that kind of setup you will be able to get to 600yards and beyond, especially if you handload.</div></div>
+1 A 20" 1/8 stainless, if you're not concerned with the weight go for the 24".
As the others have said, barrel length doesn't effect accuracy. It effects velocity which in turn plays a role in terminal ballistics. In your case that's a concern for hunting.
You should be more concerned with the quality of your barrel rather than its length. Stick with the match quality barrel makers like Pac-nor, Kreiger, WOA, Lilja, Rock Creek 5R etc.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sig685</div><div class="ubbcode-body">
I would suggest a stainless steel 20 or even 24inch 1:8 barrel, which will enable you to shoot anything up to and including 80-82 grain bullets with no problems. With that kind of setup you will be able to get to 600yards and beyond, especially if you handload.</div></div>
+1 A 20" 1/8 stainless, if you're not concerned with the weight go for the 24".
As the others have said, barrel length doesn't effect accuracy. It effects velocity which in turn plays a role in terminal ballistics. In your case that's a concern for hunting.
You should be more concerned with the quality of your barrel rather than its length. Stick with the match quality barrel makers like Pac-nor, Kreiger, WOA, Lilja, Rock Creek 5R etc.
Re: Building an AR-15 have a barrel question.
I always shoot better with 18"s or 20"s and it does increase the velocity of the bullet but what is often overlooked is what is on the barrel. The distance between the front and rear sight will dramatically increase your accuracy. If the front post is 1/16" inch from the target you are shooting at on a carbine and this is the case on a rifle length gas system the POI will not be the same.
I always shoot better with 18"s or 20"s and it does increase the velocity of the bullet but what is often overlooked is what is on the barrel. The distance between the front and rear sight will dramatically increase your accuracy. If the front post is 1/16" inch from the target you are shooting at on a carbine and this is the case on a rifle length gas system the POI will not be the same.
Re: Building an AR-15 have a barrel question.
would there be any need to go up to a 1/7 twist barrell.
would there be any need to go up to a 1/7 twist barrell.
Re: Building an AR-15 have a barrel question.
1:7 will not let you shoot any longer bullets than 1:8 twist. You need 1:6.5 to shoot 90gr bullets, but I will say that I have heard of people shooting 90s with long barrels and high velocities.
1:7 will not let you shoot any longer bullets than 1:8 twist. You need 1:6.5 to shoot 90gr bullets, but I will say that I have heard of people shooting 90s with long barrels and high velocities.
Re: Building an AR-15 have a barrel question.
Targets/ varmints are not usually very heavy bullets unless you're wacking 'em at long range.What kinda distance are we talking?
Targets/ varmints are not usually very heavy bullets unless you're wacking 'em at long range.What kinda distance are we talking?
Re: Building an AR-15 have a barrel question.
300 to 400 yards at most it will be a back up for hog hunting and used for preditor hunting.
300 to 400 yards at most it will be a back up for hog hunting and used for preditor hunting.
