AR-15 6.8 SPC build and magazines

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Aug 29, 2010
I just completed ordering the parts for my 6.8 SPB build. I decided to build a customer lower and purchase a complete upper half from Stag Arms. I'm a left hand shooter and Stag is the best offering for a south paw.

My AR-15 6.8mm SPC Left hand shopping list follows:

Lower receiver components:
Sun Devil AR-15 Multi caliber, Billet aluminum, CNC Machined Lower Receiver
RRA AR-15 Lower Parts Kit w. Nation Match 2 Stage 3.5# Trigger
DPMS AR-15 Ambi Safety Selector LR-08B
MagPul AR-15 MIAD Enhanced Trigger Guard Aluminum Matte black
Command Arms Butt stock Assembly 6-Position Commercial Diameter Collapsible AR-15 Carbine Synthetic Black (By the way the rail and storage door components are reversable on this stock to make it lef handed.)
M16 Clinic Buffer Pad II AR-15

Upper receiver parts:
Stag Arms Left-handed Upper Half Model 5HL, 6.8 SPC chamber, gas block, 16" chrome lined 1:11 twist w. magazine included
1 - 5 Rd magazine needed for legal hunting in some states

The Stag Arms online store lists 5, 10 and 25 round magazines all for $30

I have already received my order from Stag and notice that the magazine included with the AR-15 upper half was stamped with the Stag Arms logo. The extra 5 round mag. ordered was stamped ASC LLC. A quick Google search revealed that ASC is a company named Ammunition Storage Components. So they are another source of magazines. The Stag Arms stamped magazine I received looks identical in construction and are as the ASC and both are stainless steel mags. So I believe ASC manufactures the Stag Arms branded mags. You will find that ASC price is $18 for the 25 round magazines that Stag sells for $30. A significant saving!

Now, I did some additional reading about 6.8 SPC magazines and you should read about the Barrett 30 round 6.8 SPC mags. Barrett clearly makes the best high capacity 30 round magazine for the 6.8 SPC.

I'm planning to do some testing too. But that will have to wait till my build is complete.

Stay tuned and have a great day!

........... Rod
Barrett and PRI are as good as it comes and they know it. The price reflects this knowledge.

C-products mags are reliable, but good luck getting any anymore. I've heard that ASC and C-prod are somehow related. Other than the stamp on the base plate, my Stag mag is identical to my C-prod mags.
ASC is new on the scene. There seems to be quite a bit going on behind the curtain with them and C Products. What I have gathered from the ordeal is that there are some things tied up in court and has been dirty. Rumors are that ASC will be going away and C Products will be coming back. In the mean time, I am waiting and watching.

PRI and Barrett make excellent mags. If you reload, PRI will allow the longest OAL and Barrett the shortest. D&H have claimed to be releasing their 6.8 mags some time soon.
More on mags.

The info. you all provided on mags is what I'm looking for. To add to my original info. I see the ASC/Stag mags appear to use the same Magpul followers as C-Products.

Speaking of Magpul I have all Magpul mags for my 5.56/.223 AR and I'm very pleased with them. I was concerned at first with the plastic construction. They are constructed from a very strong durable polymer and I believe the inherent slippery properties of the polymer mag. housing contributes to good feeding and good fit in the mag. well. It suprises me that MagPul is not making a 6.8 SPC mag. yet.

Thanks again for all the good information.

.......... Rod
Magpul has stated that making a polymer mag in 6.8 that will work to their reliability standards is basically not possible. Issues with the stagger spacing greatly increasing the stress on the sides of the mag and feed lip geometry being the primary issues IIRC.

All the 6.8 mags that work are stainless steel; the thin material is part of what allows them to work. The 5.56 mags that the PMags replace are aluminum which is considerably thicker.
D&H is due out the third week of May, and BCM is already set up to sell them - no preorders.

Magpul has said "no 6.8" for some time. It may take Troy or Lancer to step up, the market for footlockers of 6.8 mags isn't there, compared to the millions of 5.56 being made for issue to the Marines, Army, and Brits. It's been said a production run of 100,000 mags would get every 6.8 forum member about 6.8 mags a piece. That's a small change market when your running mags 24/7 to satisfy contract demands.

Bill Wilson is using Lancer mags with milled ribs to shoot his new 7.62 based cartridge, but I suspect the larger diameter case of 6.8 will swell the mag body. It's also in part the pressure put on the follower, as a vertical coil spring keeps stacking up higher beyond what is needed to feed. For example, the Army's old caution to short load the 30 round issue mags to 28 so the first round will actually get chambered. We've all experienced how hard it is to get the last few rounds in, and the Army is directly admitting typical mag design isn't optimum.

We need an atypical mag spring in these, the answer's been out there for over 100 years and proven. It's fear American consumers won't buy them keeping it from happening.
I use Pri mags because I handload and they will accept a bullet that is seated a little longer than the normal 2.260 max length. C-product and the magazines that you mentioned would probably be just fine for normal use. I love Pmags for 5.56 and wish that Magpul did develop them for 6.8.
Rokman you should have read the thread in the string above from helotaxi and Trod. They explained why we won't be seeing 6.8 SPC mags made from polymer.

...... Rod
I did read the posts above. I guess I should have stated that I wish Magpul could develop the pmags for the 6.8. I have a ton of pmags that have never let me down. My Pri mags also have never let me down. They are just very expensive in comparison.
The C-prod mags I have will allow a longer seating length as well. 2.28" IIRC.

What's a 10/22 mag got to do with this?

The traditional coil spring in a magazine adds more pressure as it gets loaded. Hence the high feed lip pressure and swelled mag body. In this case, Ruger isn't likely using that, I suspect they have a clock spring in there, just as I hinted about in my other post.

"Constant spring pressure" can't be a stacking pressure coil spring. An unwinding clock spring does that, and the 10/22 mag is polymer, to boot. What I'm saying is the tech IS out there, a poly mag CAN be done, and it IS available for firearms. Even the better M9 mags use unwinding clocksprings, and have more capacity because of it.

The mag makers aren't going to do it because they don't think you want them. I've been beating the drum for a year now trying to get the average shooter informed why it's to their advantage. It's really about shooters simply not knowing, and once you tell them about it, the light goes on.

RUGER IS DOING IT NOW. That's going to put more a lot more knowledge out there and increase demand. Frankly, it may not be enough to meet Magpul's cost justification standards, and that's fine by me. Once a super popular maker enters the market, most of the innovation stagnates because the market jumps on them and won't see a smaller maker puts out a better product. So, sales suffer, and those guys quit making it, to our greater loss. We then are forced by economics to buy a commodity product, not the best one.

If Magpul came out with a 6.8 Pmag this year, it wouldn't be a clockspring, just something possibly shortloaded with stiffened sides to overcome the problem more cheaply. No thanks. I don't want second best, so I've learned to choose the right technology, not the Brand Name. I'm not willing to trade dollars for social elitism. Don't look up to Brand Names, consider the perspective. Look DOWN from the specification first, then you see what they lack.

For ex., what good is Colts name when you might be looking for a 6.8SPC hammerforged nitrided barrel? Doesn't even make the short list. Noveske would be about the only choice.

In the 6.8 world, Magpul chooses to be a non-starter. I don't waste my time on losers. :evil: Somebody actually making 6.8 mags is all that counts.
AR-15 6.8 SPC build complete

After being out of town and country for a few weeks I finally got around to my left hand AR-15 6.8 SPC build. You can review my list of built components in my May 6 post above. Stag supplied one 25 round magazine with the upper and I ordered a 5 rd. mag too. Later 3 - more 25 rd. mags.from A.S.C. for about $18. These are the same as what Stag supplies. By the way I'm ver satisfied with the Stag product and it is the best choice for a left hand shooter.

The build went well except the RRA hammer assembly threw me a little curve as I attempted to install the trigger and hammer before installing the selector. That didn’t work so I had to remove the hammer assembly install the selector first and then reinstall the hammer. I followed all the safety and function tests per the RRA instructions and it passed all the tests. See the attached photos of the complete rifle and a close-up shownig the enhanced trigger guard.

AR-15 8.8 SPC Complete RSs.jpg

AR-15 8.8 SPC Complete RS closeups.jpg

I took the new rifle out to the the range along with several boxes of SSA 110 gr. Pro-Hunters. I set up at 50 yards, snapped in my 5 round mag. with just one round and took a shot to test for proper function. The test was good and the bolt locked back as it should on the last round. Then I reloaded and took 5 shots and they weren’t on the paper. I took a large piece of cardboard I had in the back of my truck and set it up. This time I located a nice 1.5 inch group about 8” high and 9” right. With a little help from a guy next to me with a spotting scope we dialed it right in, I left the scope adjusted to about 1.25 – 1.5 high at 50 yds. I then tested function of all 4 of my A.S.C. mags. I didn’t experience any issues at all and consider the first outing for the 6.8 SPC a success. The next outing I will move to the 100 and 200 yard range to fine tune.

Oh! One more thing, some of my neighbors at the range were surprised at the report when I first started shooting and it was obvious I wasn’t shooting a 5.56.

As for the bore sighting! I did use a standard type bore sighter on the bench but I'm finding that they don't work well on the short (16") barreled AR platform. I think this might be do to the greater distance the scope sits above the bore. I suspect a lazer bore sighter would probably work better. I'm sure someone out there with more experience will comment on this.

Have a great day!

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