CMMG decent quality lower?

[arizonaguide]

I think I hear what you guys are saying, and thanks for the link 82. I was actually thinking about a CMMG upper as well, as I had heard good things...if they have what I'm looking for. I'll search that out in the AM.

I DO like the heavy round choices, and even though it WILL be a bit of a "trasher" gun, I still want to put something durable in it for a barrel, and will only run brass case stuff through it. We've been getting a lot of folks coming into the shop with WOLF steel cases stuck in the chamber...(maybe from extreme heat of AZ?).
So, my rule will be NO steel case/laquered ammo whatsoever. And (for sure) chrome-lined to also help prevent any stuck cases, as well as barrel life.
I probably will NOT reload, as just too much other stuff going...(ie: Pistol will still have more focus/training).

So, is 1-7 twist (16") still okay for the lighter rounds? Because what I will probably do is shoot mostly lighter FMJ (like whitebox or umc) for fun and classes, but put the heavier rounds into it for defensive purposes. Is 1-8 more tolerant of the variety of rounds, yet will shoot ALL of them with acceptable stability? Versitility and reliability will be MORE important to me than "target/match" accuracy for THIS gun. Pretty much preparing for only out to close range (probably much less<350yds) "combat accuracy" (urban/zombie/neighborhood/house-to-house/kidnapping trouble) scenarios...but super-reliable.

Will 1-8 handle FMJ in the 55 to 77grain (or bigger) reliably?
That will probably be all I shoot. Pretty much all off-the-shelf FMJ.
:)

 

[8'Duece]

I think I hear what you guys are saying, and thanks for the link 82. I was actually thinking about a CMMG upper as well, as I had heard good things...if they have what I'm looking for. I'll search that out in the AM.

I DO like the heavy round choices, and even though it WILL be a bit of a "trasher" gun, I still want to put something durable in it for a barrel, and will only run brass case stuff through it. We've been getting a lot of folks coming into the shop with WOLF steel cases stuck in the chamber...(maybe from extreme heat of AZ?).
So, my rule will be NO steel case/laquered ammo whatsoever. And (for sure) chrome-lined to also help prevent any stuck cases, as well as barrel life.
I probably will NOT reload, as just too much other stuff going...(ie: Pistol will still have more focus/training).

So, is 1-7 twist still okay for the lighter rounds? Because what I will probably do is shoot mostly lighter FMJ (like whitebox or umc) for fun and classes, but put the heavier rounds into it for defensive purposes. Is 1-8 more tolerant of the variety of rounds, yet will shoot ALL of them with acceptable stability? Versitility and reliability will be MORE important to me than "target/match" accuracy for THIS gun.

Will 1-8 handle FMJ in the 55 to 77grain (or bigger) reliably?
That will probably be all I shoot. Pretty much all off-the-shelf FMJ.
:)

My Les Baer is 1/8 twist and it's a great comprise for heavier loads. Although I still prefer the 1/7 twist rate you cant' go wrong with a 1/8 or 1/9 rate.

As JAB points out, it's about what load you are going to shoot and going to shoot for accuracy at range. With lighter loads your going to over stabilize the round with a faster twist rate and have the "hem and yaw" at 100 meters and not hit shit unless your load is accurized to the barrel. With a canelure load it's going to break quicker than you may want and cause a failure to hit the target at longer ranges. it will cause alot of damage but may not be the hit your looking for at long range.

 

[arizonaguide]

Got it! Thanks folks. :) Looks like 1-8 or 1-9 for maximum versatility. Okay, I think I've got the "list" squared away in my head now, time to start shopping around!!! See what I can find!
:cool:

 

[08steeda]

I just picked up a DPMS BA-AP416 which is a 16 inch with 1x9 twist. Got it for $250.00 Brand New in the box from a buddy who never got around to building his new rig. He got into hot water with the wife - bought an XD-45 and had to sell some stuff to cover it!!!

Any thoughts on DPMS and specifically this upper?

Arizona - this has been a great thread. I always seem to learn more and more from these guys too!

Thanks 82, KOZ and JAB!!!

 

[arizonaguide]

I just picked up a DPMS BA-AP416 which is a 16 inch with 1x9 twist. Got it for $250.00 Brand New in the box from a buddy who never got around to building his new rig. He got into hot water with the wife - bought an XD-45 and had to sell some stuff to cover it!!!

...this has been a great thread. I always seem to learn more and more from these guys too!

Thanks 82, KOZ and JAB!!!

I second that 08! And, what a great deal on the upper! Hope I can find something similar! :)

 

[koz]

AZ - For a fairly inexpensive upper, here's one you may be interested in.

http://www.pkfirearms.com/content/1/20/107/9

PKF 16 inch M4 Complete Upper

Features a lightweight military M4 profile barrel by ER Shaw, in a 16" length, 4140 steel, 5.56 NATO, 1/9 twist rate barrel, forged steel front sight tower with bayonet lug, and 1/2x28 RH threaded muzzle. Built on a milspec A3 receiver with M4 feed ramps. $495

Includes AR15 bolt group assembly and Forged Charging handle.

The guys at PK are solid and ship out quickly.
I'm not sure if the bolt assembly is HPT or MPI, you'd have to ask that.
This is not a mid-length but a carbine length.. But you could still get a free-float handguard and lo-pro gas block later on...

 

[arizonaguide]

Damn, gotta let the $$$ catch up! :) Got a line on one at work, also. But, it's a "Global" and I've not heard of them..so I think I may pass on it.
But, things are starting to come together, thanks to you folks.

 

[koz]

Pic #1 - My KISS rifle. Welded and pinned 14.5" barrel with 1/9" twist. Knight's RAS. Bill Springfield Trigger, Magpul MOE stock and grip. CMMG lower, BCM upper w/M4 cuts, BCM bolt carrier assy. H2 buffer with Silicon springs. Only two things I plan on adding to it are the enhanced trigger guard and the RRA star selector. Both are sitting on the workbench. :uhh:


Pic #2 - This is for educational purposes. Carbine gas length system on the rifle. Mid-length gas tube, then Rifle length gas tube.

Pic #3 - how far the gas tube goes into the upper receiver.

Pic #4 - Gas block fun. Standard A2 sight assembly. The stainless gas block is a Noveske from their Afghan barrel. The black gas block was a A2 gas block that met it's fate on a dremel and a grinder. Cheapest lo-pro gas block and honestly it was kinda fun to make.

 

[koz]

Pic #1 - Rear BUIS (Back Up Iron Sight) - used to be a Colt carry handle and also met a dremel, grinder, and bead-blaster. Who uses a carry handle anyway?

Pic #2 - Rifle length gas system with lo-pro gas block. 18" 6.5 G barrel with Larue 13.2" rail. *it's about to be broken down, bead-blasted and cerakoted..* You can see the gas block just in front of the rail.

AZ - if you went with a carbine length system and lo-pro gas block, you could get a mid-length free-float rail and this is what it would look like :cool:

Pic #3 - Another gas block option. YHM flip up gas block. Some people don't like these are there are only screws (rather than taper pins) holding it in place. I've never had a problem.

 

[koz]

Damn, gotta let the $$$ catch up! :) Got a line on one at work, also. But, it's a "Global" and I've not heard of them..so I think I may pass on it.
But, things are starting to come together, thanks to you folks.

Global is probably Global Tactical Supply It used to be known as Denny's guns. He's good shit..

 

[arizonaguide]

KOZ, great pic's and it really helps me understand the gas block/front sight assembly a bit better. Outstanding. I was looking at work today and noticed that (as yours shows) that they can have a small rail on top, allowing a place for a fold down front sight, or whatever. That's EXACTLY what I want to go with...a completely flat top, front to back, EXCEPT the front handguard. No, front sight except a foldown on the low profile gas block rail (if possible).

I'm thinking a completely flat top except the optic, and fold down BUIS...and a forward handguard similar to this, only in a midlength.

 

[arizonaguide]

Global is probably Global Tactical Supply It used to be known as Denny's guns. He's good shit..

If it's the same guy, the cool thing is he's local here, and about 5min from the house. Think what a pain in the ass I could be then! ;)
I don't know if that's him Koz, this upper was actually manufactured by Global Industries...local to Arizona here.
Either way, another great link (and pictures above).
:cool:

YHM flip up gas block. Some people don't like these are there are only screws (rather than taper pins) holding it in place. I've never had a problem.

Yes, that's close! That could be it. I have to compare that to a Troy folding front sight.

 

[koz]

GTS / Denny is in MO. Not familiar with Global then...

 

[JJOIFVET]

I have that lower, it is working fine for me, shot about 20k rounds from my gun and no malfunctions.

 

[arizonaguide]

JJ, what does it say on it EXACTLY? It's made in Goodyear Arizona, right?

 

[arizonaguide]

Well, I'm snapping at the bit waiting for friday to send $$ off for my lower parts...so, I'm going through the diagrams and memorizing the parts, and making sure I understand their assembly. I know most of you probably know this stuff by heart, but here's the diagrams anyway. Cheers.

And, page #2: (you can Right Click, Save Picture As, to save these to the desktop...)

 

[Diamondback 2/2]

My wife hates me! Im drunk!!!!!!!!!!

 

[arizonaguide]

Yeah, but WE love ya, Bro! >:{

 

[arizonaguide]

[ame]http://www.youtube.com/watch?v=ZJ6DGUtX3zQ&feature=related[/ame]
Cheers, Bro!

 

[arizonaguide]

Here is a link to some great videos at Brownells.com on AR platform build.
They are FREE videos that can be watched at the link here:
http://www.brownells.com/aspx/NS/GunTech/NewsletterArchive.aspx?x=v&p=0&t=1&i=1103
Both lower reciever assembly and Upper assembly are covered, as well as much more.
Cheers!