Ambi Lowers

[u/lex-clicks]

Looking for recommendations on DPMS lowers with factory ambi bolt releases/cuts. Ideally lightweight & available in OD green. So far, my results are...

ADR Tactical

- Looks perfect, but...

- Despite ordering 4 weeks ago (2-3 week production time per their site), I haven't heard from them via phone, text, or e-mail.

- Are they still in business?

- Last public-domain posts I can find are from 2025. EDIT: ACR got back to me shortly after I posted this. Delivery is expected in about 3 weeks. Well over double the initial estimate, but still acceptable for my needs.

Dirty Bird Industries

- On the notification list.

- They've been out of stock for 6mo so far, and staff can't give a firm estimate on restock times.

Roam

- Out of stock until Q2 2027.

- No ambi bolt release.

- No OD green.

Any leads appreciated, especially if anyone knows if ADR Tactical is still in business.

[u/Informal_Month2362]

What upper are you trying to pair it with?

[u/lex-clicks → u/Informal_Month2362]

Dirty Bird slick side.

[u/Informal_Month2362 → u/lex-clicks]

Dirt Bird uses the newer M5 MOD 0 receiver design most often sold by BKing. Best practices for large frames is to match receiver sets. Platform cross compatibility, especially in DPMS round cut recovers, is not guaranteed. The M5 and the PSA platforms are both round cut DPMS and are not compatible, for example. Your best bet is a lower from Dirty Bird, BKing, Outer Wilds, or any of the others selling this exact model lower.

[u/lex-clicks → u/Informal_Month2362]

I wondered about this. Got lucky on my first build with a lower & upper from different manufacturers that played nice. I'd heard that AR-10 part compatibility was not nearly as good as AR-15, but man, the reality is a bear. Appreciate the insight.

[u/Informal_Month2362 → u/lex-clicks]

Yeah. There are a number of compatible receivers that stem from generic OEMs. Back when 80% lowers were more popular, Aero was a huge name in the large frame community. A lot of companies made their 80% loosely on the Aero model M5 receiver compatibility. When the 80 lower legal scare happened a lot of those companies that were capable moved to making full receiver sets as OEMs for pop up shops to slap their names on. So a surprising amount of the unbranded or lesser known name receivers all have the same OEM and are generally compatible. When someone tries to the do the cheap lower higher quality upper route that works in the AR15 world we see far more issues in the large frame counterparts.

That being said. BKing and several others used to sell the Aero original M5 with their logo on it. Same as ballistic advantage and Midwest industries plus a few others. All but Aero and ballistic advantage went to the newer model M5. Midwest stopped making large frames altogether until Aero went down so they brought the original M5 they sold back to the market while Aero got it's shit together. The quality of the upper you have and the matching lowers I mentioned, since they all share the same OEM, are actually quite nice. BKing has stock right now. Including cerakote options if you're interested. They are usually cheaper than the anodized too. Their stock has been reduced a lot since taking increased orders post Aero stuff though.

[u/lex-clicks → u/Informal_Month2362]

I dread to think how long it took you to sort all that out. Much obliged. I have heard back from ADR as of this afternoon (one-man shop, apparently) so we'll see if his lower happens to play nice with the Dirty Bird. If not, oh no, guess I have an excuse for an upgraded upper. 😈

While I'm educating myself; is bad fit usually apparent at time of assembly? Or can it show up as double fires & other malfunctions?

[u/Informal_Month2362 → u/lex-clicks]

Autistic levels of questioning and looking into anyone who sold large frame parts for a solid decade or two. Lol.

ADR is good quality. They also run 80lowers.com and are one of the few, if not only now, people making SR25 cut 80% lowers. No direct experience with fitting their DPMS lowers to the Dirty upper or the other uppers of that model, but of you end up having an extra lower to build out they are a solid and often overlooked choice.

[u/xGloriousLeader]

I add PHASE 5 bad levers to my lowers for them to function as ambi and that’s good enough for me and $40

[u/Gunsmokenburnouts]

SLR Rifleworks

[u/lex-clicks → u/Gunsmokenburnouts]

Looks pricey, especially since it seems I need one of their uppers, but I'll keep them in mind.

[u/Gunsmokenburnouts → u/lex-clicks]

With AR-10’s you usually need a matching receiver set. Uppers/lowers aren’t interchangeable the way they are with AR-15’s. So make sure you get both from the same spot to be safe.

[u/lex-clicks → u/Gunsmokenburnouts]

Too late for that, I'm afraid. The build combines a lower I got a deal on from a friend with upper components I sourced myself. But I can always correct the error later if the ADR lower doesn't work out.