I had been wanting to build something with the AXG grip module, and after some consideration, settled on the MUP-1 80% P320 frame. There was a decent deal on the 80% frame and the jig through AB Prototype for just over $200.

It is a little pricey, and you are stuck using the jig unless you have an FCU to measure, but I figure I can loan it out to friends (ormaybe make a cad drawing of the hole layout for all the builders out there). I used all the drill sizes the jig called out but used my own personal bits. I also used the insert to bend the rails over, as directed. I have access to a mill and used the mill to clean up the slot for the safety takedown lever and for the opening on the right side for the trigger. I also cut the slide rails down with the mill to try and keep them smooth and even on both sides. After putting the slide on, I wish they were a little thicker so I could get a better fit.

I did spend a lot of time de-burring the holes, and opening a few up either with the next size drill bit or very carefully with a jeweler’s file. I recommend have all the pieces on hand to measure the pin diameters and verify the specified drill bits are the right size.

I also milled the top of the frame to fit better to the top of the grip module. Someone on the internet had reported rubbing due to that, so it was preemptive (but also looks better). There was also an interference between the ejector, the safety lever and the little tab in the rear slide plate (pictured). This made it extremely difficult to install the slide. I filed on the side of the ejector very slightly and it went away

Shopping around for parts has saved me a few bucks, between NDZ performance and gunpartscorp.com I’ve found just about everything I need.

I’ll update when I finally get it all together and shoot it. I’m also waiting on a PMM barrel and mini comp. here are the pictures.

JSD jig:



Finished FCU:







Problem areas:

This message has been edited. Last edited by: policetruck,

Finally finished the MUP-1 build, and shot it last weekend. So far, after 2-17 round mags, no hang ups or issues at all. I did clean and lube it well prior to shooting. The Parker Mountain Machine micro JTTC barrel/comp does seem to mitigate a lot recoil and make it very soft shooting.

Looks like a fun project. But sounds like WAY more work than building the Steel Frame %80 1911 I did.

I haven't done an 80% 1911 yet, but I also could have been less meticulous and got everything to fit and function. The jig is pretty easy to use though.

It only took me this long because I had other projects and was saving up for the PMM barrel/comp.

Is that comped barrel available for my M18?

I think so. Parker Mountain Machine, they have different length barrels and different size comps.

I did an AXG build recently with a compact slide and PMM micro comp. I dig it. I also put brass grips on the frame to add weight. Makes it very 320ST-esque.

Can I just stick the barrel on it like I did with the CLark my 1911?

Or do I have to buy a spring and guid erod?

It’s a barrel and comp combo. Uses the factory guide rod and spring.

Interesting project! You’re tempting me to launch another project now. Looking around, I see Ghost Gunner has MUP-1 partial frames for $100, but I can’t find anyone who has that jig in stock. Are they still making them?

Now I gotta go down the rabbit hole of researching 320 parts.