What Length Barrel Did You Choose And Why?

[Reelaction1]

I am new to this forum and after spending a large amount of time the past few days reading posts I have not been able to come up with the information I am looking for. There is so much knowledge on this website that I couldn't think of a better place to ask this question.

I have owned several AR15s but I am new to the AR10 platform. After much research I have narrowed my choices down to either the GAP or the OBR. It is just a matter of deciding which barrel to go with.

The main purpose for this AR will be for target shooting. Currently I will be shooting in the 300 - 500 yard range but my goal is to learn to shoot in the 800 - 1000 yard range. I am intrigued that one can hit a target 1000 yards away and that is a skill I would love to develop.

I have read numerous articles on the web about barrel lengths and muzzle velocity but still have questions. Why would I want a 20" over an 18" or 16". What is the advantage of one over the other. When I had my AR15s I had both a 20" and a 16". Would the 18" cover the needs of both those? Why did each of you chose the barrel length that you did?

Please feel free to direct me to other forums or websites where this information can be found.

 

[Hawk45]

Re: What Length Barrel Did You Choose And Why?

If you are purely looking to get as far as possible with the .308, barrel length is your friend. Run the numbers in JBM and see if the velocity gains/losses of the different barrel lengths will work with your planned optics setup and loads. 50 - 100FPS can be a big difference at distance. I know guys are hitting 800yds with the 16"ers, but going longer will get you there easier. I have my AR10 setup for target only, so I went with a 20" barrel. If I was going to hump it, I'd go with a lighter weight profile in 16 or 18 inch.

 

[KillShot]

Re: What Length Barrel Did You Choose And Why?

In my opinion, a 20" barrel is the sweet spot for reasons such as mobility, velocity, barrel weight, and projectile stability/trajectory. Again, that is merely my opinion and I am no expert on the matter so take it for what it's worth.

 

[AZIROC]

Re: What Length Barrel Did You Choose And Why?

I just finished my .308 ar build and I am in the same area/range you are. mostly 3-500 yard range but also dabbing in the 800-1k range. I ended up going with a 22" barrel. why 22"? I had planned on a 20" barrel during my build but when I found the barrel I wanted, JP enterprise, the cost was the same for 20-24", and the 22" gave me a few more fps and i didnt want the 24" length plus a break. so i figured 22" was a good compromise. I wish I could do a range report on my build since its been done for about a month now, but the range i go to has been closed due to electrical issues and wont be open for a few weeks.

 

[squirrel_slayer]

Re: What Length Barrel Did You Choose And Why?

I wen't 16" for weight and carrability reason's. have taken it out to 800 with no issues and according to my ballistic's chart it should make it to 1000. but I do notice it is a little more sensative to wind (as I chose a 168gr bullet)

 

[BCP]

Re: What Length Barrel Did You Choose And Why?

There is no magic number just what you want to do with it.

Generally speaking you need 20" of barrel to make 1k yards supersonic. Some barrels are faster but not always.

I have had 18" and now I have a 16". It's all I need.

 

[gladiator8us]

Re: What Length Barrel Did You Choose And Why?

I too was torn between the GAP and OBR, considered the JP LRP but for what I intend to do, target shooting and a little hunting, I decided the JP was more for serious competition. I'm not into competitive 3 gun shooting. I decided on the OBR 7.62 18". Both are superb weapons and which ever you choose you'll be happy. I made a mistake and didn't follow up pretty quickly with my FFL and thus added another 3 weeks to estimated delivery time, anticipating August to receive. I was quoted 14-16 week build time. Now comes the choice for optics and can. For these choices, I'm looking at ACOG / USO and Gemtech / Thunder Beast QD version. It's a bit of a wait but I feel well worth it.

 

[Reelaction1]

Re: What Length Barrel Did You Choose And Why?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: gladiator8us</div><div class="ubbcode-body">I too was torn between the GAP and OBR, considered the JP LRP but for what I intend to do, target shooting and a little hunting, I decided the JP was more for serious competition. I'm not into competitive 3 gun shooting. I decided on the OBR 7.62 18". Both are superb weapons and which ever you choose you'll be happy. I made a mistake and didn't follow up pretty quickly with my FFL and thus added another 3 weeks to estimated delivery time, anticipating August to receive. I was quoted 14-16 week build time. Now comes the choice for optics and can. For these choices, I'm looking at ACOG / USO and Gemtech / Thunder Beast QD version. It's a bit of a wait but I feel well worth it. </div></div>

Why did you choose the 18" over the other options?

 

[mavrick10_2000]

Re: What Length Barrel Did You Choose And Why?

It's a good split between a 16 & a 20 and the benefits of one over the other make for a tough decision sometimes.

 

[kingweb50]

Re: What Length Barrel Did You Choose And Why?

I was used to shooting long barreled bolt actions so the 20 inch semi was not long at all. It still seemed short.

 

[Luke]

Re: What Length Barrel Did You Choose And Why?

This is just my personal take on things so your mileage may vary...I've slowly been moving away from compromise guns that are neither short and light enough for serious packing or long enough for consistent long range accuracy work. So that being said, if my main goal is 1000 yard accuracy, I need to be honest with myself and realize that a bolt action might be a little better choice and while the .308 can and will shoot well at 1000 yards if I can afford it financially a 300WM or other long range cartridge might suit the task better.

If you plan on shooting mostly under 600-800 yards a .308 will work very well and makes a semi-auto platform a viable option. Since you really don't need a lot of velocity to get to those ranges, choose something with a nice short barrel in the 14.5-16 inch range to maximize your portability.

I owned a Savage 10FP 24" for many years and really enjoyed the rifle but it really showed me that it sucks walking around the woods with that big of rifle, and that even with hand loads it's a challenge to shoot at 1000 yards in field conditions. I'm not saying it was a bad setup, because it taught me a ton about marksmanship and it was the only rifle I could afford for many years. Just something to think about anyway.

 

[mysterioso30]

Re: What Length Barrel Did You Choose And Why?

You say that would go with the bolt rifle is that for wieght or for added velocity? reason i ask is over the weekend when both of us had our .308 rifles out shooting the same load 168gr horn. bullet w/ 44.4 grs of varget and both w/ 24 inch barrels my semi auto Dpms lr-308 out shot his icon by a good 75-80 fps shot for shot and the load only had 25 fps SD. wierd cause i always thought that a bolt rifle would produce faster velocitys

 

[bmt]

Re: What Length Barrel Did You Choose And Why?

I chose 18" and set a range limit of 800M.

I have shot (and hit) with the 308 farther out, but the 308 shines out to half a mile.

Beyond that, more juice is useful, not absolutely necessary, but useful.

Just my 2 cents,

BMT

 

[Luke]

Re: What Length Barrel Did You Choose And Why?

My main reason for going with a bolt action for a 1000yr rifle is the ability to chamber it in 300WM or other. No other reason than that.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: mysteryshot</div><div class="ubbcode-body">You say that would go with the bolt rifle is that for wieght or for added velocity? reason i ask is over the weekend when both of us had our .308 rifles out shooting the same load 168gr horn. bullet w/ 44.4 grs of varget and both w/ 24 inch barrels my semi auto Dpms lr-308 out shot his icon by a good 75-80 fps shot for shot and the load only had 25 fps SD. wierd cause i always thought that a bolt rifle would produce faster velocitys</div></div>

 

[RetardedTiming]

Re: What Length Barrel Did You Choose And Why?

I split the difference between 20" and 16". Very happy with my 18" Noveske barrel on my AR .308. I've been out to 700 yds with very good results. Haven't had a chance to go further yet.

 

[GrantB]

Re: What Length Barrel Did You Choose And Why?

18 or 20 is about right. I went with 20 because I can always cut it but adding is kind of hard to do and still shoot 1/4" groups. HaHa

 

[TexasAggie28]

Re: What Length Barrel Did You Choose And Why?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BCP</div><div class="ubbcode-body"><span style="font-weight: bold">There is no magic number just what you want to do with it.
</span>
Generally speaking you need 20" of barrel to make 1k yards supersonic. Some barrels are faster but not always.

I have had 18" and now I have a 16". It's all I need. </div></div>

I asked this question a few months ago when I was ordering my first AR. I couldn't decide between the 20" and the 26" barrel for .308 that RRA makes. I wanted to squeeze every bit of accuracy out of it I could, but won't be taking shots much longer than 500 yds. At that range the 26" barrel becomes unnecessarily long and heavy. I think the 20" will work much better for the application that I want.

 

[ctmyers67]

Re: What Length Barrel Did You Choose And Why?

i went with the lwrc repr in the 20" sniper barrel cinfiguration

 

[kritos666]

Re: What Length Barrel Did You Choose And Why?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: squirrel_slayer</div><div class="ubbcode-body">I wen't 16" for weight and carrability reason's. have taken it out to 800 with no issues and according to my ballistic's chart it should make it to 1000. but I do notice it is a little more sensative to wind (as I chose a 168gr bullet)</div></div>
For what its worth, I shoot 168s, but only to 600 yards. Someone suggested 175, for a class I took. I worked up a load and the 175 (with better BC) perform MUCH better at 700+. 168's seem to go subsonic past 700. I've taken the 175's out to 1k without any issues if I do my part.

 

[FromMyColdDeadHand]

Re: What Length Barrel Did You Choose And Why?

18 inches gives you rifle gas length systems in most rifles. Ballistically, there isn't that much difference that I have seen between 16 and 20, with an obvious loss in velocity, but it seems less than you'd think with good bullet selection.

I went with 18in on my MWS, though I do have a 16Cl barrel also.

 

[marduk185]

Re: What Length Barrel Did You Choose And Why?

7.5" is nice length but to truly utilize the 308's inherent glory id go 16"