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AR Sponsor: bravocompany
Posted: 4/16/2017 1:01:50 AM EDT
So I'll be getting a 14.5in BCM upper in soon (huge thanks to TNJab for that ), and I just ordered a BE Meyers 249Saker to pin on it.

Apparently, from everything I'm reading, it's long enough that it'll bring a 13.7in barrel to 16.00in, so flash hider + shim gets you to the golden zone.

What I'm wondering is this - is there any effective differences between the two lengths? Obviously the 13.7 will be <1in shorter and have slightly lower fps, but are either of those enough to actually make a noticeable difference out to 300m? It'll be a general purpose/home defense rig that I'd like to throw a Saker K at down the road, so the idea of that extra 0.8in or whatever of handling is nice, but I don't know if it's worth it, and I definitely don't want to sacrifice terminal ballistics in any meaningful way for it.

I've never worked with an AR under 16in before, outside of an 8.5 pistol, and don't know anyone who has one. For those of y'all that chopped yours to 13.7 - do you regret it? For those who have reduced barrel length by any small amount - was it noticeable?
Link Posted: 4/16/2017 1:06:24 AM EDT
[#1]
I have the same FH pinned. just to be safe, I had my barrel cut to 14in.

I enjoy the shit out of it  really makes the rifle handle better.

As far as the difference between the two, maybe a few fps, but not enough to worry about imo
Link Posted: 4/16/2017 2:52:09 AM EDT
[#2]
Cut it. 16 overall pinned is real nice. 17 oal is just nice
Link Posted: 4/16/2017 8:45:12 AM EDT
[#3]
I have noticed that velocity seems to drop off faster below 16". Terminal performance with 5.56 is very velocity dependent. As you already have the parts, buikd it and run your chosen ammo over a chono to find out for yourself.
Link Posted: 4/16/2017 11:38:56 AM EDT
[#4]
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Quoted:
I have the same FH pinned. just to be safe, I had my barrel cut to 14in.

I enjoy the shit out of it  really makes the rifle handle better.

As far as the difference between the two, maybe a few fps, but not enough to worry about imo
View Quote
Awesome, thank you for the first hand information!

Does it have a tuning fork ring at all? I'm crazy and actually kind of like the sound, but wasn't sure if the saker mount version would have it same as the full version.
Link Posted: 4/16/2017 11:41:41 AM EDT
[#5]
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Quoted:
I have noticed that velocity seems to drop off faster below 16". Terminal performance with 5.56 is very velocity dependent. As you already have the parts, buikd it and run your chosen ammo over a chono to find out for yourself.
View Quote
Unfortunately, I don't have a chrono, and once it's pinned I'm kinda stuck with it.

Do you know just how much of a difference 0.8in would make? I know it's approximately 200fps/inch, which would give me about a 150fps loss technically. Wasn't sure if that's accurate, and if it was if 200fps would make a difference in <300m shots.
Link Posted: 4/16/2017 12:29:50 PM EDT
[#6]
Some set reticle might be slightly off, but if you're using irons or a dot optic, you won't notice. The drop in FPS will be minimal. If you're using it for defense, get s quality expanding round from Hornady. It won't rely so much on the round tumbling and fragmenting to be effective.

The rifle will be louder. Once pinned, you're kind of stuck with the assembly. Pick your gas block wisely and plan ahead for what barrel nut/rail system you plan on using.

Overall, they handle much better when the overall length is at 16".

This one is a Noveske skinny barrel cut down and pinned with a BE Meyers 249F pinned in place. It has a titanium V7 gas block pinned in place with an inconel gas tube under the magnesium 13.5" KMR.
Link Posted: 4/16/2017 12:44:03 PM EDT
[#7]
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Quoted:


Unfortunately, I don't have a chrono, and once it's pinned I'm kinda stuck with it.

Do you know just how much of a difference 0.8in would make? I know it's approximately 200fps/inch, which would give me about a 150fps loss technically. Wasn't sure if that's accurate, and if it was if 200fps would make a difference in <300m shots.
View Quote
The difference is not going to be worth worrying about at all.
Link Posted: 4/16/2017 12:45:23 PM EDT
[#8]
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Quoted:
The rifle will be louder. Once pinned, you're kind of stuck with the assembly. Pick your gas block wisely and plan ahead for what barrel nut/rail system you plan on using.

Overall, they handle much better when the overall length is at 16".
View Quote
My previous build was an 11.5 with a pinned 5.5 flash hider, even with 100+yds of trees and a creek between us a friend thought I'd brought the Garand out to shoot when we were at their land.

I'm getting a 14.5in BCM SOCOM upper, carbine length with the FSP and standard barrel nut/delta ring. It's not 's SOPMOD clone, but it's SOPMOD/M4gery inspired. Ordered a DD Omega 7.0 this morning/last night.

It's sounding like the handling advantage is noticeable and the fps loss isn't. Now I just need to find a gunsmith in the area that can do a cut and weld well.

Would you recommend getting it cut to 13.7" and hitting right on at 16.00" or going with a 13.8" and having a 0.1" safety margin to make sure my dog lives a long life? I've read yes and no on running shims/crush washers for suppressor mounts, so I figured it'd be better to just cut to the right length since it doesn't really need to be timed (right?).
Link Posted: 4/16/2017 1:02:27 PM EDT
[#9]
Link Posted: 4/16/2017 1:35:38 PM EDT
[#10]
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Quoted:

The difference is not going to be worth worrying about at all.
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Quoted:
Quoted:


Unfortunately, I don't have a chrono, and once it's pinned I'm kinda stuck with it.

Do you know just how much of a difference 0.8in would make? I know it's approximately 200fps/inch, which would give me about a 150fps loss technically. Wasn't sure if that's accurate, and if it was if 200fps would make a difference in <300m shots.

The difference is not going to be worth worrying about at all.
This!
Link Posted: 4/16/2017 1:49:48 PM EDT
[#11]
It won't be as loud as that 11.5 with the noise generator, but you're still going to feel it some without a can. Your flash suppressor choice will do well. Avoid comps at all cost.

I'd recommend sending everything to ADCO for the cutting and pinning. They've never let me down and they can pin your gas block while you're there. Clamp on and set screws are cool, but pinning is far better. They're fast too. I usually have a job back in 9 days or less.

ADCO will give you that small margin of error length needed to keep your dog alive. Assuming the rookie atf agent knows how to measure and it doesn't suspiciously look like 15.9".

ADCO leaves a nice weld bead on the pin so it's obvious to any overzealous range officer that it's pinned in place. They also make sure to cut your threads concentric to the bore.



I have a lathe myself and I still send my barrel work to them.
Link Posted: 4/16/2017 2:00:13 PM EDT
[#12]
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Quoted:
I'd recommend sending everything to ADCO for the cutting and pinning. They've never let me down and they can pin your gas block while you're there. Clamp on and set screws are cool, but pinning is far better. They're fast too. I usually have a job back in 9 days or less.
View Quote
ADCO assembled and pinned my 11.5 and did a wonderful job. Their turnaround time was actually <3hrs!

Was looking to avoid a shipping cost, so I'll check if there's someone local I trust as much to do the work. If not then I'll just suck it up and pay the shipping charge.
Link Posted: 4/16/2017 8:33:58 PM EDT
[#13]
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Quoted:


Awesome, thank you for the first hand information!

Does it have a tuning fork ring at all? I'm crazy and actually kind of like the sound, but wasn't sure if the saker mount version would have it same as the full version.
View Quote
It does! It's not as noticeable as the original 249F, but it still does do it.
Link Posted: 4/17/2017 2:19:57 AM EDT
[#14]
Here's two bbl size to velocity charts that I keep in my photobucket account for reference.  Velocity is pretty much close enough to be a non issue so long as you use ammunition that'll fragment/expand at their given velocities.

Personally I think both are sexy, but I need to build a 13.7" because they are pure sex when set up right.


Link Posted: 4/17/2017 2:32:07 AM EDT
[#15]
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Quoted:
Here's two bbl size to velocity charts that I keep in my photobucket account for reference.  Velocity is pretty much close enough to be a non issue so long as you use ammunition that'll fragment/expand at their given velocities.

Personally I think both are sexy, but I need to build a 13.7" because they are pure sex when set up right.

http://i1313.photobucket.com/albums/t552/AKNorthPolar/538AB0EE-1813-4025-8EC2-179614AA4789_zpswiw22coj.jpg
http://i1313.photobucket.com/albums/t552/AKNorthPolar/IMG_4594_zps13519806.jpg
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So under 40fps and 1db difference, definitely sounds like it'll be worth it! And I'm seeing nothing but good reviews about Atwell Tactical which is nearby, so I can go with that and avoid shipping costs (I'm really running out of money for this build faster than expected).
Link Posted: 4/17/2017 1:54:23 PM EDT
[#16]
OP, get yourself a stash of gold dots or fusion soft points for social work and dont worry about velocity.

even the cheap PPU 55gr soft points would probably be better than 193 or 855.
Link Posted: 4/17/2017 3:14:30 PM EDT
[#17]
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Quoted:
OP, get yourself a stash of gold dots or fusion soft points for social work and dont worry about velocity. literally anything
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I really need to buy ammo. About 20rnds of 223 left and 0 9mm.
Link Posted: 4/17/2017 8:35:26 PM EDT
[#18]
I love 14.5" midlengths and one day soon I'd love to be putting together a 13.7" midlength upper. With the right ammo you won't need to worry about the small velocity loss between a 14.5" and a 13.7".
Link Posted: 4/17/2017 8:49:25 PM EDT
[#19]
Use good defensive ammo, which you should be for HD anyways, and you will not notice a real world difference between 13.7 and 14.5.

PSA has a good deal right now. 200 rounds of Gold Dot and 10 PMAGs for $170. Plenty of ammo for HD and you can stock up on some mags. You're basically stealing the ammo

Good price on ammo with mags from PSA
Link Posted: 4/18/2017 9:06:54 PM EDT
[#20]
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Quoted:


My previous build was an 11.5 with a pinned 5.5 flash hider, even with 100+yds of trees and a creek between us a friend thoughtI'd brought the Garand out to shoot when we were at their land.

I'm getting a 14.5in BCM SOCOM upper, carbine length with the FSP and standard barrel nut/delta ring. It's not 's SOPMOD clone, but it's SOPMOD/M4gery inspired. Ordered a DD Omega 7.0 this morning/last night.

It's sounding like the handling advantage is noticeable and the fps loss isn't. Now I just need to find a gunsmith in the area that can do a cut and weld well.

Would you recommend getting it cut to 13.7" and hitting right on at 16.00" or going with a 13.8" and having a 0.1" safety margin to make sure my dog lives a long life? I've read yes and no on running shims/crush washers for suppressor mounts, so I figured it'd be better to just cut to the right length since it doesn't really need to be timed (right?).
View Quote
So you didn't learn your lesson from that retarded and hideous 11.5" abomination?  Lol

I didn't think people in free states had a use for those asinine 5" muzzle devices.  I stand corrected
Link Posted: 4/18/2017 9:10:45 PM EDT
[#21]
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Quoted:


I really need to buy ammo. About 20rnds of 223 left and 0 9mm.
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You are an embarrassment to the great state of Texas!



Jk.  I wanna help you out cuz I love Texas (stationed at Hood for 3 wonderful years).  For deals on Ammo, SGammo.com is the absolute best but PSA sometimes has gold dots super cheap.  I'm talking $.50/rd for 75gr .223 GDHPs!  I snagged 4000 the last time they were on sale like that.  

All it cost me was my marriage
Link Posted: 4/18/2017 10:33:47 PM EDT
[#22]
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Quoted:


So you didn't learn your lesson from that retarded and hideous 11.5" abomination?  Lol

I didn't think people in free states had a use for those asinine 5" muzzle devices.  I stand corrected
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Oh it didn't look that bad! When I built it my use was solely <100yds, mostly <30yds, so the ballistics were still effective. Decides I'd rather do something different and imo good looking than just another AR build with it.

What was the use for the muzzle device? Because I'm in a free state of a free country, and I could.
Link Posted: 4/18/2017 10:38:35 PM EDT
[#23]
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Quoted:super cheap.  I'm talking $.50/rd]
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TIL I can't afford 1 bullet for my AR.

Spent all my money in replacing my blown engine, to the tune of $6700 in maintenance (and another $2-3k in parts) so I gotta work on paying all that off before I can buy anything more than just enough ammo to get me ready for and through CWTX.
Link Posted: 4/19/2017 2:34:54 AM EDT
[#24]
Differences between barrel types/manufacturers can easily give you more difference in muzzle velocity than the difference between those two lengths.


You'll also get much more benefit from picking a good projectile than adding an inch or two on the barrel.   You'll be able to get some sooner or later.  
Link Posted: 4/19/2017 6:16:37 AM EDT
[#25]
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Quoted:
Differences between barrel types/manufacturers can easily give you more difference in muzzle velocity than the difference between those two lengths.


You'll also get much more benefit from picking a good projectile than adding an inch or two on the barrel.   You'll be able to get some sooner or later.  
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This info is correct.
Link Posted: 4/19/2017 8:33:56 PM EDT
[#26]
13.7" Always!



Attachment Attached File
Link Posted: 4/19/2017 9:30:15 PM EDT
[#27]
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Quoted:
I really need to buy ammo. About 20rnds of 223 left and 0 9mm.
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Quoted:
Quoted:
OP, get yourself a stash of gold dots or fusion soft points for social work and dont worry about velocity. literally anything
I really need to buy ammo. About 20rnds of 223 left and 0 9mm.
You need to buy shit tons of ammo...
Link Posted: 4/19/2017 10:27:50 PM EDT
[#28]
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Quoted:
You need to buy shit tons of ammo...
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I'm about 2k short of what I'd like stocked up, which is about 8k short of how much training I probably need.
Link Posted: 4/19/2017 10:57:16 PM EDT
[#29]
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Quoted:
I'm about 2k short of what I'd like stocked up, which is about 8k short of how much training I probably need.
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Quoted:
Quoted:
You need to buy shit tons of ammo...
I'm about 2k short of what I'd like stocked up, which is about 8k short of how much training I probably need.
I don't think I've been under 10k for .223/5.56 (about 5k 75gr reloads, 7-9k factory ammo) in 8 or 9 years... as prices continue to fall I buy more than I normally shoot to grow the ammo fort
Link Posted: 4/19/2017 11:12:31 PM EDT
[#30]
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Quoted:
I don't think I've been under 10k for .223/5.56 (about 5k 75gr reloads, 7-9k factory ammo) in 8 or 9 years
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I don't think I've ever been in possession of 10k rounds tbh, for all the stuff we have (.22 to 30/06 in surplus). I would be buying ammo like crazy right now (get 10% discount through work and we have a lot of 62grn), but I got over $8k in car repairs I have to pay off right now. Once I can get up and ahead a bit on those I can go back to stocking up ammo and shooting a lot more regularly.
Link Posted: 4/19/2017 11:17:16 PM EDT
[#31]
Link Posted: 4/19/2017 11:47:26 PM EDT
[#32]
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Quoted:


I don't think I've ever been in possession of 10k rounds tbh, for all the stuff we have (.22 to 30/06 in surplus). I would be buying ammo like crazy right now (get 10% discount through work and we have a lot of 62grn), but I got over $8k in car repairs I have to pay off right now. Once I can get up and ahead a bit on those I can go back to stocking up ammo and shooting a lot more regularly.
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Yeah it helps to have lots of disposable income, more so if a wife is involved (they like to spent the same amount as ammo budget on shopping)
Link Posted: 4/19/2017 11:56:15 PM EDT
[#33]
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Quoted:
You'll also get much more benefit from picking a good projectile than adding an inch or two on the barrel.   You'll be able to get some sooner or later.  
View Quote
thats pretty good reasoning and to squable over an inch is silly, take the shorter and shoot a better bullet.

every time i have gone for 20 to 18, 14.5 to 12.5 i always think-wow what a difference it makes it handling.
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