New to the forum and would appreciate any advice given. I'm in the process of putting in a order for a GAP-10 G2 308, I will be using the gun mostly at the range at distances of between 100 and 1000 yards but mostly shooting in the 200-300 range. Can I please get a few opinions on which size barrel to go with, 16.5" or 18" and why as I'm looking to get educated? Thanks in advance
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Question regarding barrel size?
- Thread starter thewholetruth
- Start date
Generally speaking, the longer the barrel the greater the muzzle velocity and the shorter the barrel, the more maneuverable the rifle is. IMHO 1.5" doesn't really mean crap unless you're going to run a suppressor and then not really much. I imagine it makes sense to GAP though as they offer both flavors so run it by them before you order I'm sure they'll steer you in the right direction.
There are 3 things you need to consider; aesthetics, maneuverability, and velocity.
Aesthetics may be a completely moot point to one person and a huge deal to another (even if they might not like admitting it). On top of that, what looks better (long or short barrel) will vary from person to person, so this one is strictly on you. Do you think a longer or shorter barrel looks better, or do you even care about that?
Maneuverability is a big deal if you are using it to punch holes in something other than paper and can still be an important factor if you plan on using it for matches (or rec shooting) that has a lot of movement, firing from different positions, of different obstacles, etc. So for that, of course shorter is better.
Velocity becomes important when shooting longer distances. At a 100 yards you will not see a difference most likely between the shortest barrel and the longest, but at a 1000 you most assuredly will. The bullet is accelerating the whole length of the barrel and then free flying to the target. The faster it leaves the barrel the faster is it moving at 300 yard, or 600, or whatever. As it slows it is more affected by wind, drop, and at a certain point is moving slow enough that your groups will shoot wide open.
Think about it this way, the Marines going into a combat theater carry M4s with little short barrels that are great for moving around and the lost of velocity doesn't matter as they are not taking 800 yard shots with them, they are clearing rooms or shooting at much closer ranges. You won't see a Marine at the Nation Match though with an M4 ever, the NM M16 is the full length barrel. So you need to decide what is important for you. For me, I would go with an 18. I think it looks nice and it is plenty accurate for what I would want to do with an AR as i prefer bolt guns at longer ranges anyway. But if it was my only rifle, I would probably do a 22.
Aesthetics may be a completely moot point to one person and a huge deal to another (even if they might not like admitting it). On top of that, what looks better (long or short barrel) will vary from person to person, so this one is strictly on you. Do you think a longer or shorter barrel looks better, or do you even care about that?
Maneuverability is a big deal if you are using it to punch holes in something other than paper and can still be an important factor if you plan on using it for matches (or rec shooting) that has a lot of movement, firing from different positions, of different obstacles, etc. So for that, of course shorter is better.
Velocity becomes important when shooting longer distances. At a 100 yards you will not see a difference most likely between the shortest barrel and the longest, but at a 1000 you most assuredly will. The bullet is accelerating the whole length of the barrel and then free flying to the target. The faster it leaves the barrel the faster is it moving at 300 yard, or 600, or whatever. As it slows it is more affected by wind, drop, and at a certain point is moving slow enough that your groups will shoot wide open.
Think about it this way, the Marines going into a combat theater carry M4s with little short barrels that are great for moving around and the lost of velocity doesn't matter as they are not taking 800 yard shots with them, they are clearing rooms or shooting at much closer ranges. You won't see a Marine at the Nation Match though with an M4 ever, the NM M16 is the full length barrel. So you need to decide what is important for you. For me, I would go with an 18. I think it looks nice and it is plenty accurate for what I would want to do with an AR as i prefer bolt guns at longer ranges anyway. But if it was my only rifle, I would probably do a 22.
I'm an old fart, and my view has always been, long distance, long barrel, short distance, short barrel.
There is much anecdotal evidence supporting acceptable performance from shorter barrels at longer distances, but I've always shied away from that because I feel that the shorter barrels, and especially with the .308 as opposed to the 6.5's, need to run hotter loads to arrive out there at an acceptable minimum velocity (IMHO 1300fps or +), and that this goes against barrel longevity.
But that's only an issue if you're doing a big bunch of LR shooting. And then there's the matter of the shorter barrel being proportionally stiffer, presumably allowing better accuracy. While this is undeniable, there is also a but. The accuracy tends to come with narrowed accuracy node velocity bands, which almost demands that handloading and more assiduous load development is needed to find that/those narrow velocity bands, and that those bands tend to go out of tune more easily when temperature swings get more significant.
For generalization purposes, I fall back to my longer range, longer barrel mantra; and especially so with the .308 (I feel it's breathing pretty hard to get to 1000 at an acceptable velocity, too hard for my money).
When I build my large frame AR, it will be a .260 and will have as close to a 24" barrel as I can manage.
I wouldn't build a short range large frame AR, because at touchee-feelee distances, the .223/5.56 is enough gun for my purposes. and operating within close confines is the only justification that makes a carbine length AR practical for me. I do maintain a 20" Mossberg MVP Predator.223 for use as a walkabout/truck rifle, and a 16" lightweight AR Upper, and that's my main contribution to owning a carbine length collection.
My other walkabout rifle is my .30-06 Savage Axis II deer hunter. For larger game, bring enough gun. A .30-06 is enough gun, period. I build nearly the same ammo for it as my Garand, substituting SP Spitzers for the hunter.
Greg
There is much anecdotal evidence supporting acceptable performance from shorter barrels at longer distances, but I've always shied away from that because I feel that the shorter barrels, and especially with the .308 as opposed to the 6.5's, need to run hotter loads to arrive out there at an acceptable minimum velocity (IMHO 1300fps or +), and that this goes against barrel longevity.
But that's only an issue if you're doing a big bunch of LR shooting. And then there's the matter of the shorter barrel being proportionally stiffer, presumably allowing better accuracy. While this is undeniable, there is also a but. The accuracy tends to come with narrowed accuracy node velocity bands, which almost demands that handloading and more assiduous load development is needed to find that/those narrow velocity bands, and that those bands tend to go out of tune more easily when temperature swings get more significant.
For generalization purposes, I fall back to my longer range, longer barrel mantra; and especially so with the .308 (I feel it's breathing pretty hard to get to 1000 at an acceptable velocity, too hard for my money).
When I build my large frame AR, it will be a .260 and will have as close to a 24" barrel as I can manage.
I wouldn't build a short range large frame AR, because at touchee-feelee distances, the .223/5.56 is enough gun for my purposes. and operating within close confines is the only justification that makes a carbine length AR practical for me. I do maintain a 20" Mossberg MVP Predator.223 for use as a walkabout/truck rifle, and a 16" lightweight AR Upper, and that's my main contribution to owning a carbine length collection.
My other walkabout rifle is my .30-06 Savage Axis II deer hunter. For larger game, bring enough gun. A .30-06 is enough gun, period. I build nearly the same ammo for it as my Garand, substituting SP Spitzers for the hunter.
Greg
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A very smart person told me when in doubt get a 20" Barrel, it will still be lighter than most LR barrels it is the absolute best for Barrel harmonics and when adding a suppressor it's still is in within reasonable length.
And a lot of people will tell you that the length of the barrel has no bearing on the guns accuracy which is technically true but!! A longer Barrel makes it easier to be accurate as with a shorter Barrel it really amplifies any mistake on your part.
And a lot of people will tell you that the length of the barrel has no bearing on the guns accuracy which is technically true but!! A longer Barrel makes it easier to be accurate as with a shorter Barrel it really amplifies any mistake on your part.
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Some really good advice here. Honestly, the difference between 16.5 and 18 inches is negligible. The longer barrel isn't going to give you that much more velocity and the shorter barrel isn't going to be that much more manueverable. My bias has always been to use the shortest barrel I can get away with for my intended use. And, as others have pointed out, it's really how you intend to use the rifle that will make the decision for you. If you're only going to be shooting off a bench at longer distances, get a long, heavy barrel. If you're only going to be shooting offhand, at short distances, where you're required to move, get the shortest, lightest barrel you can. For the uses you've described, either a 16.5 or an 18 will totally fit the bill.
Finally, not to muddy the waters, but if you think you might end up doing a bunch of shooting at 600+ yards, you might think about getting a 6.5 creedmoor gun, rather than .308. Ballistics will be significantly better at longer range.
Finally, not to muddy the waters, but if you think you might end up doing a bunch of shooting at 600+ yards, you might think about getting a 6.5 creedmoor gun, rather than .308. Ballistics will be significantly better at longer range.
