Wait, so let me get this straight. This is a OBS configuration frame that technically should not not exist, but it does, and while legal to possess couldn't be made into an OBS configuration since it was made after the determination letter for the RPBs in the 80s. This is the MAC equivalent of the Title 1 M203 receiver, you just can't put the 40mm barrel on it......that's really stupid. Well I'll just go ahead and order this thing then because I'm willing to do a conversion to closed bolt semiautomatic. I mean this thing seems like a good M10 frame.
So I guess my question is, would you feel comfortable ordering one of these things or not really?
Sort of… the trigger hole location is the same on the open bolt guns and the closed bolt RPB/cobray/MPA/VMAC guns (but
NOT the Texas M10A1s, so those old gunbusters Texas mac kits won’t work in this frame with those holes where they are).
This frame can be built into a closed bolt semi auto, using MPA-10 parts, but you would need to drill the 2 hammer holes and 2 safety selector holes (optional). The frame can also be readily assembled into an open bolt semi-auto, or full auto only configuration, without any drilling, if you have one of the old RPB sear carriages, or fabricate one yourself. If you wanted to build it up into a select fire machine gun, the 2 holes for the SMG selector switch/sear pin would have to be drilled.
So technically it’s not
just open bolt configuration, it can be assembled either way depending on which parts you choose. I am not sure how the AFT feels about the frames without sear blocks but I know for a fact that at some point in the 90s, “FMJ” (another Wayne/Sylvia Daniel company) sold M11/9 pistols and M12 pistols, as well as stripped frames, that didn’t have the sear block installed and had the hole for the open bolt sear stud present on the bottom.
Maybe they slipped through the cracks… but I don’t think the sear block matters. Truth be told, as collectors and enthusiasts, we tend to be much more aware of the laws pertaining to these particular guns as well as the different hole placement for closed bolt vs open bolt etc…
I can assure you that the average AFT field agent is totally clueless when it comes to Ingrams and Ingram accessories. I know this from personal experience. They seem to be informed about the poly 80 glock frames and 80% AR lowers (
to the point of tunnel vision), but totally clueless when it comes to MAC flats, frame weld sets, hole placement etc… I have actually witnessed an AFT field agent asking her colleagues if a ventilated slotted barrel extension for a MAC was a suppressor.
Maybe there are still some veterans who have not retired yet that have been around since the 90s, when MACs were all over the place, but the average AFT agent in their 20s-30s just doesn’t have much if any first hand experience with these guns, and most of them aren’t “gun guys” either, so it’s not like they’re researching the nuances of different MAC-10s on their free time.
They are no longer the first pick of criminals like they were 40 years ago, so the AFT probably isn’t wasting time and resources putting together powerpoint presentations about MAC flats for their field agents.
So the TLDR -
The frame is fine, it could be built up either way, closed or open bolt (SOT only), and the AFT doesn’t care about these or consider them to be machine guns. It’s a semi auto title 1 pistol frame, it will transfer as such on paper and it won’t backfire on you down the road.
