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Length vs purpose

iukamedic

Sergeant of the Hide
Full Member
Minuteman
Aug 31, 2017
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I feel sure this has been covered at length at some time. I understand that there is no do all
in ar’s but if a person was to lean toward what they would consider the the rifle they went to as there goto what would it be? Length and purpose.
 
If I were looking for a generalist ar, I’d look to the 3gun crowd for inspiration. They’re hosing paper at halitosis range and then shooting out to several 100 yards with the same rifle.
 
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If I were looking for a generalist ar, I’d look to the 3gun crowd for inspiration. They’re hosing paper at halitosis range and then shooting out to several 100 yards with the same rifle.
Bad breath range?
 
Lately I'm digging the 13.7 because it's about as long as I can handle for a suppressed carbine while still remaining handy and it avoids a tax stamp. I see no reason for more unless someone is doing a dedicated precision type fun.
 
All of the barrel lengths for all of the things.
I'm missing a 19" currently but I might fix that soon. I'll probably use it to shoot point blank range at some point while I use my 10.5" for 500 yards. Because life is all about options.
 
11.5-12.5” if you’re going to run it suppressed.
14.5” unsuppressed or if you’d like to avoid going the sbr/pistol route.
 
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I feel sure this has been covered at length at some time. I understand that there is no do all
in ar’s but if a person was to lean toward what they would consider the the rifle they went to as there goto what would it be? Length and purpose.
Because we have Byzantine gun laws and you did not specify the purpose of the gun or caliber, as a do it all I would pick something like The LMT MARS-H with a 16" barrel in .308 or the new Geissele SD in 6mmARC.
 
I feel sure this has been covered at length at some time. I understand that there is no do all
in ar’s but if a person was to lean toward what they would consider the the rifle they went to as there goto what would it be? Length and purpose.
Opinions will obviously vary quite a bit. However, there is a main question that you should resolve before deciding on a barrel length:
Will this rifle ever run a suppressor?

If so, it changes what is "practical" in terms of barrel length, gas/buffer set up, and a few other little things.

I've come across all manner of opinions from folks with more knowledge/experience than me ranging from 11.5" to 18" as an "ideal" general purpose set up.

Also, what ammo will you be feeding it? It's a lessor consideration, but eventually it may matter to you how well the barrel length plays with ammo choice.
 
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Bad breath range?
Yes, Peter Hathaway Capstick’s poetic way of describing up close and personal encounters with those bent on bad things. In his case, the African big 5. (Close enough that you can smell the decaying flesh stuck between the teeth of the male lion that is actively hunting you…)
 
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16” with free float hand guard and LPVO.
Works for guys with bad breath and still can shoot 2” groups at 1000 yards. Ok I totally made that last part up. More like 2” at 100 yards.

/thread
 
Watching guys shooting short barreled AR Pistols with braces yesterday - while attempting to hit a 10" plate at 200yds - drove home the idea to them that a rifle works better!
 
That's not a gear problem. But it's comforting to blame why you suck on the firearm.
Well, in their defense - TulAmmo isn't really known for being the best ammo on the market. LOL
 
I was trying to be kind....
I thought about that one day with a co-worker. He COULD NOT get his G19 zeroed with an RMR. I asked if I could try as he was shooting all over the place at 7y. I shot 5 9mm bullets into one hole.

I handed the gun back to him and told him the gun was zeroed. He got a little pissed but it proved my point.
 
I know that I am not even close to the best but my groups really open up with a 10.3" shooting IMI 77s out past 400 yards.
Specs:

IMI 77SMK @ 2440fps
Triarc 12.5” mid length
A5 buffer system
standard BCM BCG
OSS 762 QD + flash hider
Vortex PST 1-6 MRAD (dialed to 525)
Scalarworks 1.93” mount
Atlas CAL gen 2 bipod
Gamechanger rear bag, lite fill
Larue MBT 2S Flat at 4.5lbs (2.5+2).

Coyote steel target at Silver Creek Range (Mobile, AL) during an Orion Training Group class.
 
You can legally travel state-to-state with a silencer without gaining approval from the ATF. The same cannot be said of a short barreled rifle. For that reason alone, I would suggest that the shortest barrel length that is practical for a do-it-all rifle is 16 inches. A "K" can and some good quality electronic ear plugs (or muffs) would be a winning combination. I haven't pulled the trigger yet, but I'm strongly considering a 18" barrel, rifle length gas system, 223 wylde chamber, for my next AR build.
 
Specs:

IMI 77SMK @ 2440fps
Triarc 12.5” mid length
A5 buffer system
standard BCM BCG
OSS 762 QD + flash hider
Vortex PST 1-6 MRAD (dialed to 525)
Scalarworks 1.93” mount
Atlas CAL gen 2 bipod
Gamechanger rear bag, lite fill
Larue MBT 2S Flat at 4.5lbs (2.5+2).

Coyote steel target at Silver Creek Range (Mobile, AL) during an Orion Training Group class.
Okay you got me wrong, I was not doubting you. I was saying I can't do it with my MK18. My groups start to open up somewhere between 350 and 400 yards. I responded to you and mentioned the 10.3" in the post because I was wondering if the extra two inches would make much difference.
 
You can legally travel state-to-state with a silencer without gaining approval from the ATF. The same cannot be said of a short barreled rifle. For that reason alone, I would suggest that the shortest barrel length that is practical for a do-it-all rifle is 16 inches. A "K" can and some good quality electronic ear plugs (or muffs) would be a winning combination. I haven't pulled the trigger yet, but I'm strongly considering a 18" barrel, rifle length gas system, 223 wylde chamber, for my next AR build.
I have not either but I am leaning towards a 20" barrel.
 
deer-hunting.gif
 
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Okay you got me wrong, I was not doubting you. I was saying I can't do it with my MK18. My groups start to open up somewhere between 350 and 400 yards. I responded to you and mentioned the 10.3" in the post because I was wondering if the extra two inches would make much difference.
I’m not sure, I’d assume you’re probably at 2350ish FPS. Assuming you can dial/hold correctly, and your rifle is up to the task in relation to target size, you should be able to make impacts.

Keep in mind my target was not a 5” plate, but a full sized (looked that way) coyote target. So I definitely had some wiggle room. Should be taking this rifle (ACOG equipped now though) to a local DMR match on 7.24 from 25-520y on IPSCish size targets. We’ll see how that goes.
 
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20 inch barrel, rifle gas with an A5 buffer lets you shoot everything from 55gr to 90gr VLDs.
 
Thanks for all the replies. I have a service rifle and leaning toward a lighter weight 20. thanks again for all the input.
 
Thanks for all the replies. I have a service rifle and leaning toward a lighter weight 20. thanks again for all the input.
So you were soliciting opinions to make a purchase decision? Stating that in the OP as well as a definition of what your idea of a "do all rifle" might have gotten some better answers.
 
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Thanks for all the replies. I have a service rifle and leaning toward a lighter weight 20. thanks again for all the input.
We had approximately 22 barrel length suggestions, from 10.3” up to 20”.
A quick approximation and we find the average suggestion is…

15.5” barrel length.
 
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This kind of surprised me. Not much difference between 11.5" and 16"

I went the 14.5" route. Good compromise for me and a 13.7 wasn't available in the gun I bought.
 
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16” with free float hand guard and LPVO.
Works for guys with bad breath and still can shoot 2” groups at 1000 yards. Ok I totally made that last part up. More like 2” at 100 yards.

This, but I'll add with a decent SS barrel.

16" is short enough to be wieldy, even somewhat with a short can and not deal with SBR laws or the likely upcoming pistol classifications, but can make effective hits to 600 yards and can be stretched to 800 with good match ammo although the effectiveness of a 5.56 is pretty nill out there.

14.5 pin and weld is all fun and games until you decide you want to change the rail or gas block or change the muzzle device for a new/different can or to add a can later. With 16" + at worst you're heating up the device or soaking it in water to get the threadlocker or rocksett to release to get it off.
 
A person definitely needs to get the components right before p&w'ing. Probably not a good option for someone building their first AR. It's also a plug for buying receiver kits from companies that have a large selection of handguards that are compatible with their barrel nuts like SLR.

Yeah but better stuff comes out and shit also happens. I've gotten a bad SLR adjustable gas block before that had to be replaced. Had I put that on a P&W barrel I would have had a big issue. Just don't think it's worth it to save 1.5".

P&W stuff is also far harder to sell on the secondary market if you decide you don't want it.
 
This, but I'll add with a decent SS barrel.

16" is short enough to be wieldy, even somewhat with a short can and not deal with SBR laws or the likely upcoming pistol classifications, but can make effective hits to 600 yards and can be stretched to 800 with good match ammo although the effectiveness of a 5.56 is pretty nill out there.

14.5 pin and weld is all fun and games until you decide you want to change the rail or gas block or change the muzzle device for a new/different can or to add a can later. With 16" + at worst you're heating up the device or soaking it in water to get the threadlocker or rocksett to release to get it off.
The pins are pretty easy to defeat. Roll pins are the easiest. Just unscrew as normal. Pws uses a solid pin. That one was fun but not too terrible. I also have all the associated tooling to do the job. Drill press, lathe, welding equipment. So I can see for some it's more of an issue.
 
You can test a P&W assembly as a pistol with a brace before doing the P&W. I wouldn’t do a P&W as a first gun - you should know what barrel, gas block, muzzle device (and suppressor since you need to know the internal depth of the blast chamber to spec the muzzle device) and handguard you want after building some experience.

16” is the easiest thing out there and gets you most of the velocity that factory .223/5.56 ammo will produce.
 
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So you were soliciting opinions to make a purchase decision? Stating that in the OP as well as a definition of what your idea of a "do all rifle" might have gotten some better answers.
No. Not my intention. A service rifle is set up and is good for service rifle competition. Not a jack of all trades. I don’t think there is such a thing as a do all rifle. Sometimes for someone that doesn’t have the funds for several there might be a set up that can fill a couple of roles. Didn’t mean to ruffle feathers. Just thought it might be a good discussion.
 
We had approximately 22 barrel length suggestions, from 10.3” up to 20”.
A quick approximation and we find the average suggestion is…

15.5” barrel length.

This is a perfect suggestion - short enough to require a tax stamp, but too long to offer any of an SBR's advantages. I now know what I must build next.