Hey guys I have a few lowers and trying to see what barrel lengths to build or buy. I already have a 20in for my M16A5 build and I need 2 more uppers. Should I get 16/14.5 and 10.5 or 11.5? I already have AR9 with AR9 lower and 7.62x39 upper with a P80 lower. I went a little crazy when my LGS had a sale on lowers
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AR barrel lengths
- Thread starter Pro2AJuggalo
- Start date
What are you trying to do with them?
How do you see yourself using them?
How do you see yourself using them?
I'm building the 20in for longer distance and I'm seeing what's the smallest I should go, it's going to be suppressed so should I go with 10.5, 11.5 or stick to longer barrels like 14.5 and up. I have 3 lowers to build so I'm getting some ideas on what to build
14.5 is my favorite do all ar length but 12.5 is growing on me especially with a can. I don't notice much difference in drop out 400y and that's about my practical limit with a red dot
Yes. Get all the barrel lengths. Because this is America.
Seriously though, use case dictates equipment. You can't just pull barrel lengths out of a hat and figure out what they're for later.
Well, you can but cmon..
Seriously though, use case dictates equipment. You can't just pull barrel lengths out of a hat and figure out what they're for later.
Well, you can but cmon..
I would get one either 10.3/10.5/11.5 and one 14.5. One shorty and one not so shorty.
PB
PB
I already have 5 different calibers between my pistols and ARs so I'm not really trying to have too many more. I'm kinda thinking about 300bl but idk it's kinda expensive and I would rather spend it on 308 but we'll see. What were you thinking?
Honestly the only reason I want to build a smaller one is for the Block clone, those are badass!
Lots of questions to be asked before giving answers.
1) what’s your budget, all in, for these 3 uppers?
2) what barrel for the 20” and what ammo are you going to feed it?
3) must you immediately build uppers for your spare lowers?
4) are you building a pistol or an SBR if you got with with 10.5/11.5/12.5?
5) you said a shorty would be suppressed. Do you have the suppressor in hand, or at least have the paperwork in process? Even with Eforms, shit is still a 300+ day wait after certification, so closer to 11 months all in.
6) Have you considered standardizing the muzzle devices on all 3 uppers so each can use the same suppressor across multiple guns?
1) what’s your budget, all in, for these 3 uppers?
2) what barrel for the 20” and what ammo are you going to feed it?
3) must you immediately build uppers for your spare lowers?
4) are you building a pistol or an SBR if you got with with 10.5/11.5/12.5?
5) you said a shorty would be suppressed. Do you have the suppressor in hand, or at least have the paperwork in process? Even with Eforms, shit is still a 300+ day wait after certification, so closer to 11 months all in.
6) Have you considered standardizing the muzzle devices on all 3 uppers so each can use the same suppressor across multiple guns?
Those are the 2 I been thinking about. I kinda don't have a use for shorty besides just to have one built but feel like if needed a 12.5 should be small enough for home defense but that's why I'm asking might be good sizes to have
I don't really need one but there's different uses for different sizes I didn't think I needed to write a book to explain why I want and have the amount of guns I have. I'm seeing what's the most beneficial sizes to have. For Home defense is it better to have a 10.5 or should I stick with my 20in? Do I need a legit reason to want multiple guns? Do I need my G3? No but I have it. Do I need my RPKs? No but I wanted it and I have 2. I love guns simple as that
Is that grendel? Hmm I'll think about it what I'm going to do. Thank you and I'm guessing you like it's ballistics?
I went through the phase of 1980s Colt Sporters and Sporter IIs, then Bushmasters in the early 1990s, then M4forgeries, then 3-Gun set-ups, AR-10s, more free-float/Cerakoted/nice trigger ARs, then 6.5 Grendel starting in 2009.
Grendel ruined the AR-10s for me, and I had an irrational infatuation with AR-10s. I thought a 7.62 NATO CAR-15 would be the answer to all my dreams.
Grendel ruined all of that. Low recoil, can see your one hits, fits in AR-15, kills critters of all types, does long range, HD, close range, busts cinder blocks apart for fun, and hits steel hard.
I like the short barrel Grendels the most.
It changes the AR-15 into something different. I can’t get excited about anything 5.56 anymore, and I really like 5.56 NATO.
Im not a clone guy but my clone buddy tells me I have one, I think. Thats a pricy game, I know that much.
PB
That gave me chuckle, I'd go 15.5529. Much better ballistics.
14.5 is about the lowest I would go, I have one 14.5 and it’s probably my favorite in 223/5.56 once you drop below it your giving up a ton of velocity per inch, and the headache of sbr or having it be a pistol, if you want something shorter than 14.5 I would suggest dropping down to 8 or 9 inches and going blackout and just pay the tax stamp.
I love my 18" Alexander Arms Grendel and just got a 12" after running some numbers:I went through the phase of 1980s Colt Sporters and Sporter IIs, then Bushmasters in the early 1990s, then M4forgeries, then 3-Gun set-ups, AR-10s, more free-float/Cerakoted/nice trigger ARs, then 6.5 Grendel starting in 2009.
Grendel ruined the AR-10s for me, and I had an irrational infatuation with AR-10s. I thought a 7.62 NATO CAR-15 would be the answer to all my dreams.
Grendel ruined all of that. Low recoil, can see your one hits, fits in AR-15, kills critters of all types, does long range, HD, close range, busts cinder blocks apart for fun, and hits steel hard.
I like the short barrel Grendels the most.
It changes the AR-15 into something different. I can’t get excited about anything 5.56 anymore, and I really like 5.56 NATO.
A 12" Grendel with 123gr bullets has as much terminal energy (~400 ft-lbs) at ~700 yards as an 18" 5.56 shooting 77gr bullets at ~550 yards...
I love my Mock SPR, but a 12" gun that hits harder at long range with mild recoil is pretty dang wild. When Precision Firearms started offering 7.5" Grendel barrels, I ran some numbers and was laughing out loud when I saw the ELD 123gr would match the terminal energy of the 18" SPR shooting 77gr at 500 yards
. Yeah, flight time and drop are going to be big factors, but a backpack/truck gun that hits like the Mk12 at 500 yards sounds stupid fun.I just got an 8.5” Grendel barrel from PF, a Criterion.
Some initial predictions about velocities with lighter weight bullets seem to indicate that it will surpass 16” 5.56, and match 20”.
I just need to decide on handguard and suppressor set-up.
Looking at 80gr Hammer bullets initially, along with factory 90gr TNT from Federal.
90gr TNT factory ammo averages 2698fps from my 12” Grendel.
With 110gr PPU factory ammo from the 12”, I’ve experienced higher hit probability/1st-round hits at 780-900yds on 2-3 MOA targets.
The 110gr is really flat, and I used my program data for 107gr SMK just to get a register. Connected 1st-round at 780yds, followed by 2 more with ease, then went to 900yds and connected 1st-round.
This is the range. The buffalo is at 780yds. The round plate below it is at 400yds, which you can hit with no effort. My 8yr-old son connected on it 1st-round, first time he ever shot at 400yds. He’s been begging me every day to go back, but the mountain pass has been icy or I’ve been buried with work.
I normally show up there, and start shooting 123gr ELD-M factory ammo at the 400yd plate, then go to the buffalo, or even just go straight to the buffalo. No dialing, just using the GRSC reticle. Too easy.
When I connected 1st-round at 900yds, I used the 900yd stadia line and about 2 dashes to the right, holding left into the wind with 110gr PPU. The 110gr was noticeably flatter than 123gr.
I have a 10.5” Criterion build that just needs glass, and the 8.5” that I’m still working out.
Some initial predictions about velocities with lighter weight bullets seem to indicate that it will surpass 16” 5.56, and match 20”.
I just need to decide on handguard and suppressor set-up.
Looking at 80gr Hammer bullets initially, along with factory 90gr TNT from Federal.
90gr TNT factory ammo averages 2698fps from my 12” Grendel.
With 110gr PPU factory ammo from the 12”, I’ve experienced higher hit probability/1st-round hits at 780-900yds on 2-3 MOA targets.
The 110gr is really flat, and I used my program data for 107gr SMK just to get a register. Connected 1st-round at 780yds, followed by 2 more with ease, then went to 900yds and connected 1st-round.
This is the range. The buffalo is at 780yds. The round plate below it is at 400yds, which you can hit with no effort. My 8yr-old son connected on it 1st-round, first time he ever shot at 400yds. He’s been begging me every day to go back, but the mountain pass has been icy or I’ve been buried with work.
I normally show up there, and start shooting 123gr ELD-M factory ammo at the 400yd plate, then go to the buffalo, or even just go straight to the buffalo. No dialing, just using the GRSC reticle. Too easy.
When I connected 1st-round at 900yds, I used the 900yd stadia line and about 2 dashes to the right, holding left into the wind with 110gr PPU. The 110gr was noticeably flatter than 123gr.
I have a 10.5” Criterion build that just needs glass, and the 8.5” that I’m still working out.
I have a few pin-weld 13.7/ 13.9" and for not dealing with NFA issues, I really like the balance of size, "wieldiness" and practicality. One has a red dot and one a LPVO. I acknowledge that a lightweight 16" barrel is not harder to use. And the pin-weld works best if youre settled on suppressor or not, and if so, which. But the 13.x feel nice in hand.
And then I would do a 11.5" for the second.
Without knowing too much on usage or budget, staying within 556, and generally oversimplifying, the 20" is your precision/ long range, the 13.x with a LPVO is your jack of all trades, and the SBR/ pistol with red dot checks the small category.
And then I would do a 11.5" for the second.
Without knowing too much on usage or budget, staying within 556, and generally oversimplifying, the 20" is your precision/ long range, the 13.x with a LPVO is your jack of all trades, and the SBR/ pistol with red dot checks the small category.
Do you shoot suppressed?
11.5/12.5 mid length gas
16"
And your 20" seems like a good set up imo.
You interested in other calibers?
300 blk, 6 arc, etc?
I been doing some thinking and I'm getting rid of my 7.62x39 uppers and going with a different caliber and now it's between 300bl and 6.5G. I'm leaning towards 6.5G just on price alone and ballistics. I almost gave up because I'm trying to save and stock up on the calibers I have but I'm not trying to replace firing pins and extractors. I haven't read too many consistent problems with 6.5G ARs
Especially with the prices of 7.62x39 rising to where they are now, I think 6.5 Grendel makes sense all day long. Let me send home this perspective with the following observations:
A 16.3” AK or AR-15 chambered in 7.62x39 will spit a 122-123gr bullet out at around 2350fps. Those rounds will go subsonic at around 475yds at sea level.
A 12” 6.5 Grendel will spit a 123gr out at around 2300fps and will pass the 7.62x39 within 50-75yds, then maintain supersonic reach out to 950-1100yds, depending on which bullet.
An 8.5” Grendel will pass the 16.3” 7.62x39 at 150yds, and maintain supersonic reach out to 875-950yds.
Down for either…and have both an intermediate caliber (6.8 for me though), as well as several 300BLK uppers.
If you want to shoot subs, especially suppressed, 300BLK all day long, but a good intermediate cartridge is a no brainer. Again, I went 6.8, but 6.5G is a damn fine cartridge. However, if I was starting fresh today, I’d almost certainly go 6 ARC vs any of the others.
YMMV
If you want to shoot subs, especially suppressed, 300BLK all day long, but a good intermediate cartridge is a no brainer. Again, I went 6.8, but 6.5G is a damn fine cartridge. However, if I was starting fresh today, I’d almost certainly go 6 ARC vs any of the others.
YMMV
12.5 to 16 inch is the sweet spot for 5.56. just decide what your minimum terminal ballistic needs are.
