Trying to make my final decision before purchase what would the pros and cons be for an 18" vs a 16" barrel??
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AR 16 or 18" barrel
- Thread starter the once-ler
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Barrel Length Studies in 5.56mm NATO Weapons here's a study on MV vs barrel length. Looks somewhat exponential from about 5" till 11", then then you get somewhat linear gains till about 20" where you more or less get diminishing returns (based on these results anyway)
I'd say if you want to try and stretch it a bit, go 18". If you're looking for 300 yard or so 16 should be fine. I'm not an expert by any means though.
Edit: You probably could go even further with a 16", but I haven't looked into it.
I'd say if you want to try and stretch it a bit, go 18". If you're looking for 300 yard or so 16 should be fine. I'm not an expert by any means though.
Edit: You probably could go even further with a 16", but I haven't looked into it.
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You can run longer gas systems on 18" barrels to lengthen the recoil pulse while getting a modest velocity increase, but comes at a cost of weight (taper dependent) and size. I have two 18" - One MK12 from Centurion and one Noveske 18" LW self build. The MK12 tops in accuracy, but it's set up far differently and might be I simply shoot it better. It's a heavy pig though in comparison, and I'm fast as hell with the Noveske (3-Gun setup).
A 16" mid-length barrel is one of the best compromises out there for AR barrels, but it is still a compromise like most choices in barrels. My two 16" builds are handy as hell, but I shoot both 18" builds better. A brake on a 16" puts a good bit of concussion towards the shooter as well; learned that with the build I did for my lady. It induced a flinch and I'm switching it over to a flash comp to mitigate.
It really comes down to this though... What are you doing with it?
A 16" mid-length barrel is one of the best compromises out there for AR barrels, but it is still a compromise like most choices in barrels. My two 16" builds are handy as hell, but I shoot both 18" builds better. A brake on a 16" puts a good bit of concussion towards the shooter as well; learned that with the build I did for my lady. It induced a flinch and I'm switching it over to a flash comp to mitigate.
It really comes down to this though... What are you doing with it?
I think twist is as important as length.
My 16in 1/7 twist will shoot 69/77g out to 400y every well, almost as well as my 20in 1/9. My 20in 1/9 will out shoot everything I own with 55gr.
I am going to order a new barrel for my project gun (long range 600 to 1000m) but can't decide which one, seems 20in 1/8 is the way to go. $500 budget.
My 16in 1/7 twist will shoot 69/77g out to 400y every well, almost as well as my 20in 1/9. My 20in 1/9 will out shoot everything I own with 55gr.
I am going to order a new barrel for my project gun (long range 600 to 1000m) but can't decide which one, seems 20in 1/8 is the way to go. $500 budget.
If you are going to ride your belly or a bench, get the 18".
If you want maneuverability, and the ability to shoot from positions well, get the 16". Get a 1/8 twist either way, .224 Wylde chamber if you care about accuracy.
If you want maneuverability, and the ability to shoot from positions well, get the 16". Get a 1/8 twist either way, .224 Wylde chamber if you care about accuracy.
^^ These posts for the WIN!! ^^ This is all good info to soak in as you try to make your selection.
Let your ultimate goals with the rifle dictate which barrel is best suited for YOU/YOUR NEEDS. What distances will you be shooting primarily and what do you need to accomplish at those distances? Are weight/maneuverability a concern for you? What types of ammunition will you be shooting with the rifle in question (this is more an issue of selecting the best chamber for the barrel...not the length)? etc., etc., etc.
Two 5.56 uppers, both barrels are bull weight, no muzzle devices (NY).
One is a Stag 24" Super Varminter, The other is a CMMG 16 Bull WASP.
I figure if we're going long, we're going long, and if we're going short, we're going short.
The 16" is an acknowledgement that not all applications are way out there in the wide lonesome,
Greg
One is a Stag 24" Super Varminter, The other is a CMMG 16 Bull WASP.
I figure if we're going long, we're going long, and if we're going short, we're going short.
The 16" is an acknowledgement that not all applications are way out there in the wide lonesome,
Greg
Ok well I think I have made a decision as to the route I am going. I do quite a bit of bench shooting and at longer distances so the POF 415 with an 18" barrel is the gun I will buy so I have a complete rifle from the get go. Then I will also start a build on a DI upper with high end parts for strictly range use.
Depends on your desired application for the rifle... I built a SPR with a rainier arms 18" Ultramatch barrel in 223 wylde chambering w / intermediate gas length and I am beyond satisfied with it.
I used to build only 16" ARs because they are more compact and I figured just as accurate. A few years ago I built my first 18" because I wanted a MK12 mod 1 clone. I've been sold on 18" for .223 ever since. The difference in trajectory is quite significant. I bought a KAC LPR last year and really don't notice the extra length or weight over a 16". The 18" will shoot noticeably flatter. If you want compact then get an SBR.
I bought a Colt LE6920 M4 last fall that I installed a Geissele SSA-E trigger and ordered a complete WOA 18" varmint upper with a 1 in 7" twist for more accuracy and longer range with 69 grain Sierra Match King bullets. I also am having the barrel full length fluted to save some weight. It should look similar to this.
http://www.whiteoakarmament.com/xcart/product.php?productid=17555&cat=261&page=1
http://www.whiteoakarmament.com/xcart/product.php?productid=17555&cat=261&page=1
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Good choice on the POF 415. Mine is a 16" 415. Except for my Noveske N4 SS Afghan It is my most accurate 223/556.
16" are pretty noticeably handier. It def makes a difference. The weight is at the end of your lever arm and the length...I find it pretty noticeable.
Your first one, get a 16." I am starting to go to 14.5" guns with pinned muzzle devices. Between 16" and 18" trajectory difference won't be meaningful until 400 yards.
Your second gun, try someone's 18" and see if you like it. They are much more noticeably front heavy. Note that the 20" bbl original M16's had pencil barrels and light handguards. They are going to be much lighter than your average current production 18" bbl with a medium contour.
Your first one, get a 16." I am starting to go to 14.5" guns with pinned muzzle devices. Between 16" and 18" trajectory difference won't be meaningful until 400 yards.
Your second gun, try someone's 18" and see if you like it. They are much more noticeably front heavy. Note that the 20" bbl original M16's had pencil barrels and light handguards. They are going to be much lighter than your average current production 18" bbl with a medium contour.
No clue where that is. The military even trains soldiers with that knowledge. The m16 is less accurate than the m4, due to barrel length. My 20" remmy 700 tactical is more accurate than a 24", and I'm thinking about going with an 18" next. You get less velocity, however. GPS defense sniper school trains and teaches that a shorter barrel will be more accurate at range than a longer barrel. The highest velocity I'm getting in my remmy 700 is only 2580fps with a 175gr SMK and 42.0gr of h4895
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I would base my decision on how the gun balances off hand. If you're going to use a heavy buttstock like a Magpul PRS I would do an 18-20". 16" if you're using a light buttstock.
I don't think whatever you're shooting at is going to care if the bullet is going 2850fps or 3050fps. Plus, it is presumably a .223 so it's not a hammer or a laser.
I don't think whatever you're shooting at is going to care if the bullet is going 2850fps or 3050fps. Plus, it is presumably a .223 so it's not a hammer or a laser.
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I agree. I don't want to be shot with any of it. But if you are not wanting to track game like a 250lb boar then a little more speed will help drop their asses DRT.
I have a 18" 1/8 barrel and am able to take it to 900 yards with a little work. But at that point my scope is out of adjustment and I'm holding over. 69gr SMK
800 is a piece of cake.
With a 16" barrel I'd imagine I'd be out of scope by 800 already due to the velocity loss
800 is a piece of cake.
With a 16" barrel I'd imagine I'd be out of scope by 800 already due to the velocity loss
Again, the .223 is not a hammer. Not at 2850 and not at 3050. If 150 ft. lbs. loss in energy at the muzzle means the differance in tracking and not tracking a 250 pound animal it's time to go to a larger caliber. IMO.
