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View Full Version : 1:7" twist rate, longer barrels, best manufacturers, AR ammo 5.56mm vs. .223


Mr.CRC
10-10-2009, 8:00 PM
Hi:

I've come close to buying a Daniel Defense DDXV, but now that I've learned about low-profile gas blocks, I want to hold out for a rifle with one of those.

I don't really like the conical plastic hand guard of the typical AR, and especially don't like the high profile front sight. I want to have a configuration that allows experimentation with various sight systems, particularly iron sights, as well as red dots and telescopes.

One thing that concerns me about Daniel Defense barrels is the 1:7" twist rate. I know that this twist rate is good for the heaviest bullets. Does it cause problems for lighter bullets? What is the situation with throat erosion? Can too tight a twist rate compromise accuracy? I probably will want to shoot "medium" weight bullets in the 55-69 gr. range.

Until I can get a low profile upper from DD, I will have to shop elsewhere. I have discovered LaRue. I'm interested and willing to pay for high-mid to top quality, so if there are other names I should consider, please chime in.

Noticing that LaRue has longer barrels than 16" is also interesting. I mainly want an AR-15 for target shooting, plinking, cool factor, and 2nd amendment exercise. So accuracy is important. I don't want to go to a 24" though, because some flexibility for potential HD application is also a lesser objective.

18" or 20" sounds about right, for a little more speed and accuracy. What other makers should I look at for longer barrels and low-profile uppers?

I've also heard it said that for accuracy oriented shooters, .223 might be preferable to the 5.56x45mm. Should I consider an AR chambered in .223 for my application? If so, who makes these?

A related question is, would one be likely to get less accuracy from an AR chambered in 5.56x45mm if they shoot .223 ammo?

Which chambering affords more ammo flexibility (to a non hand-loader) and easier availability?

A lot of questions, I know. I like to thoroughly research before I start a new project.

Thanks for feedback!

Cyclepath
10-10-2009, 8:39 PM
1:7 Twist rate is fine for 55-77 Gr. Anything lighter than 55gr may be an issue due to the fast twist rate. The bullet can yaw or in theory tear itself apart from the high spin rate.

Larue, DD, Noveske, White Oak Armament, BCM, LMT, Sabre are names to consider

Get it chambered in 5.56 so you can shoot .223 safely. Some manufacturers make Wylde .223 chambers that can safely shoot 5.56. Rock River\Larue comes to mind.

qtmac_mien
10-10-2009, 9:41 PM
YHM are also nice

http://yankeehill.bizland.com/store/media/YHM-8810_bg.jpg

i have that complete upper with a spikes lower and ctr stock..the finish is perfect..u can get them in 1:7 or 1:9 twist

fcr
10-10-2009, 10:01 PM
You can easily remove the F sight from the XV. Get a low profile gas block and do all you want with the DDXV. It is a tough rifle to beat at that price right now. You can still put on an Omega Rail with the rebate and experiment with different sights and systems. Look at what the troops carry, they have F sights standard issue and have all kinds of scopes if that is what you are looking for. If money is no object, Noveske, LaRue if you can get one in CA., LMT, LWRC, Knights if you can get one in and so on. Or build your own from parts, BCM. You will end up with exactly what you want. This site and AR15.com M4 have all kinds of info. Brownells has how to videos. Look at LWRCs if you want a longer barrel.

technique
10-10-2009, 10:29 PM
For an 18-20in SPR or like type...

Colt
BCM
Saber
WOA
Larue
Noveske

55gr ammo is standard and it will be fine in a 1/7.

Anything can have a lowpro GB if you choose...ARs are like legos, you can build or interchange as you please.

.223 wylde might be something you may consider...but the average distance you will be shooting should be considered as well...I wouldn't bother if you only shoot at a max of 100yards.


As for rail systems...In techs world there is only ONE, Daniel Defense.
Larue and Vltor are nice too...my world excepts them for who they are.