knowledge help with lefty upper

[J.O.]

I'm in the process of building an AR for the wife in 556. She shoots rifles left. She tells me she wants the shells ejecting left and not to the right past her face. I say okay no prob I'll build you one. I'm just finishing up the lower and now moving on to the upper and I have questions that I can't seem to find the answers to. This is my first lefty AR and I'm still learning about how it all works. I could use some help from you guys.

Current Lower stats:
JD Machine Tech 5.56 multi cal receiver
TDS Guns Stainless LPK
RockRiver Winter Trigger guard
Spike Tactical "6 position w/dry film"
Spike Tactical "17-7 stainless"
Spike Tactical "ST-T1 buffer
DSA castle nut
Phase 5 "REVO SAS" sling attachment
Ergo Ambi Pink grip
Magpul stock MOE Pink (waiting to be released)
Phase 5 "EBRv2" bolt catch (soon to be pink)
KNS Pins Gen2 Mod2 (soon to be pink)
Battle Arms safety selector Ambi Pink

So after all that I'm now moving on to the upper. My plan is to use:

Stag lefty 556 upper receiver w/ ejection port cover door
Spikes M16 NIB carrier (standard)
DPMS south paw bolt assemlby (reverse throw one for use in standard carriers) http://www.dpmsinc.com/AR15-Southpaw...ete_p_655.html
Centurion Arms CHF 1:7 14.5" Mid-Length
Spikes Mid-Length 304 Melonite gas tube
JD Machine Tech 5.56 Muzzle Brake
Centurion Arms low pro gas block
Centurion Arms C4 rail 10"
Rainer Arms Raptor Ambi charge handle
Ergo pink rail ladder covers

1) What I need to know is, do you guys see any problems with the upper working with the parts I've chosen?
the bolt is supposed to be a reverse rotation to throw the shells left but is for use in standard carriers.
2) Do the lefty ejection door size and location differ between DPMS & Stag?
3) Is there a shop or company that you can recommend that would be willing to help me decipher this? I'm in the market for the upper parts now and I'm willing to buy them from a shop that is willing to help me build this.

When I call stag, they tell me I have to use all stag parts for a lefty upper and will not explain why. When I call DPMS they tell me the same exact thing and won't explain it to a newbie. Doesn't make sense to me that I would have to use only one companies products.

I live in the IE but am all over so cal on a daily basis for work. From SD to LA.

Please help thanks.

[.40CALIbear]

Just buy the Bcg from stag too. They are the originators of the left hand AR. I'm sure they got all the querks worked out by now. Dpms quality kind of went down the drain after Remington took over.

[.40CALIbear]

From what I read on arf.com, lefty parts are really hard to come by right now. So good luck on your search

[J.O.]

I've located most of the parts online. They do have lead times, some stretching 3-6 month. But I don't want to buy the parts, wait 6 months, then find out it doesn't work. I've been researching for months. Asking every shop I stop by and call. No one seems to know or care. Posting my questions here on calguns was my last ditch effort to get to the bottom of it before I just start buying parts and make it work.

[J.O.]

Just buy the Bcg from stag too. They are the originators of the left hand AR. I'm sure they got all the querks worked out by now. Dpms quality kind of went down the drain after Remington took over.

The problem with buying the complete bcg from stag is those are extremely hard to come by with minimum 6 month lead times. If I ended up breaking a part I'd be screwed. Plus the stag bcg requires the use of an ambi barrel extension. Which would mean that I would have to buy that and a barrel from stag as well.

The dpms reverse rotation bolt is allot easier to come by and standard carriers are as well. Plus with use of a standard carrier, I can use standard barrels and extensions.

[J.O.]

Any body????

[mcisniper]

Have you called Stag? It may be easier to order a complete upper.

[Yemff]

you cant mix stag and dpms, the bolt rotates in different directions for each. a Dpms bolt won't even fit in a stag upper

[J.O.]

Have you called Stag? It may be easier to order a complete upper.

Yes I've called stag on several occastions. I've have yet to find someone that wants to help. I get the basic, buy all of our stuff or it will never work attitude (they've litterally told me that too). They will not tell me why. They just try to push me into buying a complete upper from them or one of their suppliers. Honestly I'm so turned off by them, at this point I don't really want to buy any of their products. However, they're the only ones making a standard a3 lefty uppper with duct cover. What I'm trying to stay away from is using proprietary parts. I'm trying to use as much standard milspec parts as I can.

[J.O.]

you cant mix stag and dpms, the bolt rotates in different directions for each. a Dpms bolt won't even fit in a stag upper

Yes I'm aware of the bolt rotation. Where in the stag A3 upper comes in contact with the dpms bolt? Inside the A3 upper receivers should be essentially the same, mirror images of each other lefty or righty assuming they both should be "milspec" just ejecting differently that I can think of. Both carriers would be "milspec". I have not figured out why the stag requires an ambi barrel extension. Thats just what stag tells me. I've read on several forums and even Spikes tactical of people not using ambi extension. They've had no cycling problems. The m4 feedramps I would think should be fine but obviously I'm new at this. Why would the dmps bolt not fit? they would be using milspec size carriers and bolt wouldn't they? (just in lefty configuration)

[Obviously a Plant]

When I first started shooting, having a lefty AR was very important to me.
I own both Lefty and Standard uppers, and I prefer the latter, because of the way I can manipulate them, looking into the chamber when I need to and the ease of replacing/ changing parts. I have never had a problem with brass ejecting in front of my face and only occasionally enjoy throwing brass to my left. Although that is likely not an option, it is worth considering...

As to the Stag vs. DPMS, I'm not much help, except to say that with the Stag ambi-barrel extension you can mount any barrel, not just a Stag. I believe it is required because of the threading on standard barrels, but I haven't taken apart my upper to look.
The upper, bolt and bolt carrier (and extension) are the only parts you need that are different from a standard- buy them all from one company. Imagine calling Ford and asking if you could drop a Corvette engine in a Mustang, do you think they would be very helpful (or even know)? Choose one set-up or the other for your upper and enjoy shooting it rather than troubleshooting it, or get a standard and enjoy shooting it sooner-
It took me 7-8 months to get my lefty upper, by which time I was in love with my BCM...

Good luck.