To cut...or not to cut?? (bbl advice PLZ!)

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[ARCHIVED THREAD] - To cut...or not to cut?? (bbl advice PLZ!)

Posted: 9/8/2005 9:56:09 PM EDT

That is the question...

I have a 1/7 Colt LE6920 and seem to be talking myself into the idea that by cutting my 16" bbl down to 14.5 and pinning a good supressor (Vortex) would yield easier room to room transitions for CQB (room clearing).

I am reasonable proficient as is but less is more sometimes.

I would have this professionally done (likely by SpecArmorment) but don't wanna lose too much in the process (velocity/range etc).

Also, I will be using the 75g TAP NATO rounds.

Any input would be greatly appreciated!!

Posted: 9/8/2005 10:00:30 PM EDT

[#1]

At the range you are referring to, a 1.5" bbl loss wont make that much difference.

Posted: 9/8/2005 10:21:15 PM EDT

[#2]

Is it a chrome-lined barrel? I was under the impression that cutting a chrome-lined barrel down was a bad idea? Or is it just a job for a specially skilled gunsmith?

Posted: 9/8/2005 10:28:23 PM EDT

[#3]

Not to mention recrowning.

If I only had a mill..

Posted: 9/9/2005 6:12:30 AM EDT

[#4]

And where did you get your TAP Nato rounds sir?

Posted: 9/9/2005 6:17:41 AM EDT

[#5]

spend the money on practice ammo.

Posted: 9/9/2005 6:19:18 AM EDT

[#6]

Quoted:
spend the money on practice ammo.

+1

Posted: 9/9/2005 6:38:40 AM EDT

[#7]

If you add up the differences, you only shave about an inch off of total length, if that means anything.

The barrel length difference is 1.5", but a Vortex is about 1/2" longer than an A2, so your total saving is 1".

If you feel that you absolutely need that one inch, go for it, but that's alot of pain and suffering to go through to shave an inch off your rifle. I'm not a door kicker, CQB guy, but I can't see where an inch would save you anything. Hell, if you notch your buttstock out, you just lost it. On the flip side, notch your buttstock in one and lose that inch without mods.

Posted: 9/9/2005 7:34:12 AM EDT

[#8]

I would sell the 16 inch barrel on the EE and buy a 14.5 Colt barrel to replace it with. That way tou dont have to worry about the chrome lining getting messed up and you get to keep the barrel markings. Plus it may be cheeper because you wont have to pay to have it cut and re parked.

Posted: 9/9/2005 8:52:26 AM EDT

[#9]

What kind of CQB are you doing? it dosent sound like your a door kicker (no offense of course) but if your just going for the shorter look then get it cut which you can do for very cheep...personnally I would keep the barrel and buy and another short upper that way you could have a close range and a Mid range rifle
As for CQB like Mongo said...your not losing anything with going shorter, but you could use the stock method. Hell you could use a 7.5 and it all does the same thing in the house!

-so if your going for the look...then go ahead and cut it
-if your going to be doing a lot of CQB/DA then get a much shorter barrel

Posted: 9/9/2005 8:58:55 AM EDT

[#10]

Quoted:
And where did you get your TAP Nato rounds sir?

here

Posted: 9/9/2005 9:01:17 AM EDT

[#11]

Quoted:
What kind of CQB are you doing? it dosent sound like your a door kicker (no offense of course)

Why would I be offended? You don't even know me? I would be upset if you were on my squad and said my 7+ years of Narcotics enforcement meant nothing...but since you aren't, no offense taken. :)

Posted: 9/9/2005 9:03:48 AM EDT

[#12]

Have you thought of the SBR route and getting a 11.5' bbl?

Posted: 9/9/2005 9:20:19 AM EDT

[#13]

LOL!!! Most snipers don't sound like they shoot people at great distances either.
NO, I'm not a sniper, but I've met a couple. Wouldn't have known it if one wouldn't have been wearing a scout sniper T-Shirt. Met them later that year in the field, their guns were way cooler than mine...

Posted: 9/9/2005 9:28:56 AM EDT

[#14]

Quoted:
Quoted:
What kind of CQB are you doing? it dosent sound like your a door kicker (no offense of course)

Why would I be offended? You don't even know me? I would be upset if you were on my squad and said my 7+ years of Narcotics enforcement meant nothing...but since you aren't, no offense taken. :)

Get another barrel. If you are doing this every day, and feel that it will make that much of a diference, then do it. I ran my duty weapon as a 14.5" w/Phantom for a long time, and while the difference isn't much, it is there. For some unrelated reasons I'm now using a 16" barrel, but eventually, I'll probably go back to a 14.5".

I would actually recommend getting a different upper, and then leaving your 16" version as a training weapon.

Posted: 9/9/2005 9:31:21 AM EDT

[#15]

Quoted:
Quoted:
What kind of CQB are you doing? it dosent sound like your a door kicker (no offense of course)

Why would I be offended? You don't even know me? I would be upset if you were on my squad and said my 7+ years of Narcotics enforcement meant nothing...but since you aren't, no offense taken. :)

Aw....just have to becareful around here with words...you know how some guys get...
since you are in a active CQB role whats your departments regs on SBR's like mentioned above,or is this for personal use? I would think for your job I would go real short if you could....like 10.5 and keep it low-profile cause you know how some of these crack houses are!

and I would go with what stick said about the upper....
I use a 10.5in for my duty weapon....in the house.

Posted: 9/9/2005 10:09:04 AM EDT

[#16]

Quoted:
Quoted:
Quoted:
What kind of CQB are you doing? it dosent sound like your a door kicker (no offense of course)

Why would I be offended? You don't even know me? I would be upset if you were on my squad and said my 7+ years of Narcotics enforcement meant nothing...but since you aren't, no offense taken. :)

Aw....just have to becareful around here with words...you know how some guys get...
since you are in a active CQB role whats your departments regs on SBR's like mentioned above,or is this for personal use? I would think for your job I would go real short if you could....like 10.5 and keep it low-profile cause you know how some of these crack houses are!

and I would go with what stick said about the upper....
I use a 10.5in for my duty weapon....in the house.

It is actually my personal weap but can use it. I use it for personal defense mainly.

My delima is that the Dept provides Benelli entry guns (12ga 14" bbl) and I got spoiled with CQB scenarios using such a short bbl. Now I grab my 6920 and feel like it is a deer rifle when practicing in the hot house.

If I decided to do this it would be done professionally through Specialized Armament Warehouse in AZ. That is where I bought it and, as far as I know, they do great work! Tina said there is no issues at all to be considered with chrom lines bbls as long as you do it correctly (cut it cold).

Anyway, thanks a ton for the input........decisions, decisions....

EDIT: Also, since it will be mostly home def weap.... I am concerned about getting too short (even if I could) for over penetration concerns. At 10.5" I would be afraid of losing enough velocity to reduce frag chances and putting my family in harms way....if ever needed of course ...

Posted: 9/9/2005 11:34:54 AM EDT

[#17]

Ya! thats why I keep my kimber worrior by my bed and I have a tac Shotgun with Rubberball ammo if If need it. AR's are a little much for Home Def.

Posted: 9/9/2005 4:56:15 PM EDT

[#18]

Actually, after studying the ballistics, I am convinced that it is better suited that handgun ammo. I know it is a debate that is, and will be, raging but I'd rather know I have outgunned anyone coming into my home to do harm.

Posted: 9/9/2005 5:14:47 PM EDT

[#19]

Quoted:
spend the money on practice ammo.

Listen to Bigbore he knows his shit just like all the guys at Adco(theres my line for you guys

)

but seriously you wont see that much of a difference,stick to the 16" and buy some ammo or some mags. Or check into the dept's SBR policy made theyll spring for one for you.

Posted: 9/9/2005 5:51:23 PM EDT

[#20]

I cut, crowned and threaded one of my 16"s down to 14.5" and added a pinned Phantom and liked it so much I did the same thing with my other 16".

Here's VELOCITY and FRAG INFO for 14.5", 16" and 20" barrels with various loads.

Posted: 9/9/2005 7:13:52 PM EDT

[#21]

Quoted:
I cut, crowned and threaded one of my 16"s down to 14.5" and added a pinned Phantom and liked it so much I did the same thing with my other 16".

Here's VELOCITY and FRAG INFO for 14.5", 16" and 20" barrels with various loads.

great work on the charts...but if I am reading them correctly you are giving up up to 100 fps at any given range for 1.5"...right?

I gotta say the idea of giving up 50 yards of reliable frag range is concerning and got me thinking....

Please correct me if I misread this. Looking forward to more input.

Posted: 9/9/2005 9:25:46 PM EDT

[#22]

I found this interesting when looking at 14.5-inchers.

ammo oracle...SBR's

Q. My department is considering using 10" or 11.5" barrels for our ARs. They are so cool, and everyone knows that all the real go-fast, high-speed, low-drag operators use SBRs. Plus, Robert DeNiro uses one in "Heat." What's the best ammo to use to poke big holes in the bad guys with these?

We dislike this question. We dislike it because of its premise. The premise is that 10" or 11.5" barrels are good choices for law enforcement or defensive use. We strongly disagree with this premise. Some of us actually dislike even 14.5" barrels, in fact.

The primary wounding mechanism for .223 and 5.56 ammunition is fragmentation. The primary factor in fragmentation is velocity. The primary velocity booster is barrel length. 11.5" barrels barely bring milspec (NATO) 55 grain FMJ to 2700 fps (the critical fragmentation threshold for many FMJ .223 rounds). Accordingly, any distance at all drops the rounds below fragmentation velocity. 10" barrels are unlikely to ever get rounds above fragmentation velocity at all.

If you are saddled with a department mandated SBR we recommend the following:

1. A marathon letter writing campaign citing the Ammo Oracle often persuading the powers that be to see reason and potentially save lives by giving you REAL weapons, not toys.

2. Use heavier rounds known to fragment at lower velocities and do more tissue damage such as:

68 grain Hornady Match OTM
69 grain SMK OTM
75 grain Hornady TAP
77 grain Nosler OTM

Obviously, you should probably have a 1:7" twist.

Under no circumstances should you take comfort in the assurances your armorer gives you that the latest soft point or hollow point law enforcement specialty round will solve the problem. Most likely it will not. Soft point and hollow point rounds lack penetration even at high velocity. Because they are not prone to yawing or fragmentation lower velocities will not increase penetration as with many fragmenting rounds.

[ARCHIVED THREAD] - To cut...or not to cut?? (bbl advice PLZ!)

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