Anyone have a fixture or gcode for one of these yet? Im just getting started on a MR1 and dont wanna turn my 80% into a paper weight.
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I haven’t done that style/model of 80% before. Knowing the differences between 15/10/308 models I’d be hesitant to say anything would 100% be the same aside from the trigger/fcg pin spacing.
If I can remember the forum where I got my other drawings I’ll reply with it. All I can remember is it was a “member only” forum with no public view. If you get the information, do leave us some breadcrumbs to follow 
I’m sure there are others that might be interested.
Yeah, a pistol caliber build like yours that takes Glock mags is way different, even from the Colt / DOE type that took the modified Uzi mags. I think you may be hard pressed to find what you are looking for, but I second what Skipshift said – please let us know if you do find something.
A clean workflow for doing 80 percent lowers is a beautiful thing.
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Id be interested to see what you come up with. I have done an AR-15 lower on the MR-1 and it worked without issue. I have see that lower on the 2A Part Picker Facebook group, but no one mentioned too paths.
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Precisely where I brought mine I’m working on getting code apparently it exists! Hang tight!!!
Aren’t you supposed to get jigs to go with 80%ers to help you align all your essential features?
I 3D printed a jig and used locating pins in it to align everything. If I were to do another, I’d mill the jig. There are jig plans everywhere for an AR-15 lower. The 3D printed jig worked, but it vibrated so the surface finish isn’t great.
The lower Gopnik has will be harder to find a jig for. I believe it is for a Mac11 upper receiver and is based on a 3D printed lower.
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Correct! Ive talked with the designer and was told it’s similar to an AR-15 trigger pocket but narrow in some spots unlike a traditional AR-15 FCG pocket.
I designed a clamping fixture/jig for Ar10/15/308 so I can run 15s on one side, flip it over and run 10/308 on the other side. Milled out of aluminum plate and uses steel pins to locate the reciever. It’s pretty handy for when I decide to mill out one or the other for a new project.
This MAC reciever seems interesting though. Not particularly my flavor of gun, but hey… if I can make one, then why not give it a shot in the future 
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Hey man! Do you have the files for this? Or did you custom make it?
I’m actually from the 3D printing community and I am only just getting into milling. I am very good at 3d modeling but I’m looking for the easiest and quickest way to finish 80% AR-15 lowers as well as a 308! Would LOVE something like this that lets me do both quickly.
I’m sure if it’ was printed in carbon fiber nylon at 100% infill it wouldn’t shake at all. I used PET-CF 100% to raise the level-detecting button
It’s just something I put together on the fly and it worked. I should still have a rough draft model that I used to lay out hole positions. If I can remember I will send it to you this evening.
The AR10/308 side has larger holes to match the diameter of the takedown pin holes on the reciever. Both lowers locate using the takedown holes as well.