I am in the process of building a couple of new uppers for my AR. One of them is going to be a 6X223 and the other I have yet to decide. It will be one of the following: .30HBR, 6.8 SPC or a 6.5 Grendel.

Has anyone here actually built a complete upper Assy. for an AR?

What I am planning is:

1) new bolt & carrier with a .223 & PPC sized bolt. This way I will be able to change the bolt itself in the carrier when changing uppers with diffrent case head sizes and the bolt will be matched to the barrel.

2) Adjustable gas block so I can adjust each barrel for optimum performance.

3) Flat top upper for the best ability for mounting optical sights.

4) Free float forward handguard with lower rail for mounting bi-pod as needed.

5) Medium to medium heavy 18 - 20" SS barrel & target crown, no break/flash hider as they actually hinder optimal accuracy.

About the only thing that I've done in the past with ARs is build up lowers and changed barrels in the uppers in the same caliber - 5.56/.223 and each time I changed the bolt in the carrier as each blot wears with the original barrel.

I am asking for opinions & ideas, What cha think?? Thanks

I have built a couple of uppers in 223 and am currently working on a 6.5 Grendel with a 24 in barrel. its a pretty simple process so I should be shootin this weekend.
I am using an adjustable gas block from EGW, a Kreiger barrel,and a Bushmaster varminter free float hand gaurd. The bolt and carrier and upper are from Alexander Arms
There is a website that addresses barrel change out and is very helpfull with the details. I don't know how to post a link but the site is RB Precision. The site contains a huge amount of info on ARs.

Good luck with your build and whatever it turns out to be.

Some other links are:
http:www.ar15.com and www.varminthunters.com...ndex.shtml
www.varminthunters.com/ar15tech/

If you go with the 6.8 please let me know how it does. Thinking about an upgrade on a lower that I have.

After a bit more researching on the web I have now found a source that I can also get 7MM Benchrest, 6MM Bench Rest & 30 BR. I didn't know that you could get these cartridges in an AR but it looks like that they have been working out well for those that have them. I am now revising my thinking toward the 7MM BR, it will give me better performance than my 7 TCU and that was a fine whitetail cartridge. Still have an open mind and weighing my options.

How many do you need? I've assembled more than I can count(thanks to uncle sam) nothing to it with the right tools, If you have a Lathe you have more than a couple options.......

What do you think of the DPMS A3 (Flattop) Upper assy with Fwd Assist?
Or would you go with another make for a build up? I've seen a lot of uppers made by companies and many of them use DPMS for their custom builds.

*** mc223 ****

Where did you get your 6.5 Grendel, I don't know of anyone yet liscenced by Alexander Arms to produce the barrels to their specs. My understanding is that AA will be liscencing a few barrel makers and that there are a few dimentional diffrences between it and a 6.5 PPC. Please let me know I would be interested.

Thanks all for your info please keep it coming.

I like Bushmaster for fit, I have had a few DPMS that the trigger pin holes and hammer pin holes were not drilled straight and that was a pain.
Armalite is also good. I prefer Bushmaster though.
The forward assist is Ok if you need it, other wise its just in the way, I have built a few flat tops for folks with great results, The last one I used a Savage heavy stainless fluted barrel in 223 rem. It shoots with my Bushy Vrminter with lighter bullets

OOPs sorry, need to fevise my last statement, It was Olympic lower recievers that gave me fits, not DPMS, DPMS are fine as far as I can see.

How is your AR build going????
HELLLLoooooooooooooo!!