JSD Supply MUP-1 Frame

$99.00 - $264.00
(9 reviews) Write a Review
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This is a new JSD 80% frame to build yourself a custom or self-built P320. It will work with any P320 9mm, 40SW or 357SIG (not manual safety without modification). Will also work with 45ACP with minor modifications. All GEN 3 frames fit the new drop parts (frame tab cut). Please note these are now the Gen 3 P320 frames offered by JSD. Inside is laser marked by JSD, among other minor changes. Frames are still compatible with JSD jigs. (Add a discounted jig above).

Frame requires finishing to be a complete firearm. All city, state and Federal laws apply when manufacturing your own firearm. Engraving is available for an additional fee. Engraving info can be found HERE.

Includes: 1 JSD Supply MUP-1 (SIG P320) Unfinished Frame (Manual safety cut available for +$55) (Discounted jig available for +$110).

FCU Parts, Barrel, Slide, etc. are obviously NOT INCLUDED. 

No FFL is REQUIRED. THIS IS NOT A FIREARM. JSD has their ATF determination letter stating this is not a firearm.

See our option to add the manual safety pocket to your existing frame: Manual Safety Cut

9 Reviews Hide Reviews Show Reviews

  • 5
    well made unit

    Posted by Ralph Koon on May 31st 2021

    very professionally made

  • 5

    Posted by Barrett Grubb on Jan 27th 2021

    Excellent frame and jig.....Not hard for someone with medium gunsmithing experience to complete with their jig and instruction videos...these sigs are a bit pricey to build in comparison with glocks but in the end the trigger capability on the sig is much better and I guess you get what you pay for to an extent....overall happy with the purchase and shipping was amazingly quick during a time when a lot of places are late getting stuff out.

  • 4

    Posted by Marc Silberberg on Jul 9th 2020

    Broke two bits on the #39, but was all around easy to do.

  • 5
    Sig mup

    Posted by Oswaldo Herrera on Feb 22nd 2020

    Well made.

  • 5
    worked excellent just take your withit

    Posted by ron on Jan 25th 2020

    good stuff

  • 5
    Excellent Customer Service

    Posted by j on Jan 24th 2020

    Excellent customer service. Walked me through some issues with my build and got it resolved!

  • 5

    Posted by Steve on Aug 3rd 2019

    You will not find better customer service , faster shipping, or better prices.

  • 5
    Great part

    Posted by Eric on Jun 26th 2019

    As expected. Great part for another build. Yes it's a little rougher than previous version, but I polish the internals anyway. Came out great and easy install.

  • 3
    A lot rougher than I thought

    Posted by Matthew Biek on Mar 27th 2019

    I know it is not a completed part, but this was a lot less finished than I thought. There were large scrapes and sharp edges on all the stamped surfaces. The over all dimensions seemed pretty accurate, and I am sure the part with work. Like I said I just didn't expect it to be so rough.

    AB Prototype Response - Thanks for the input. We dont manufacture the JSD frames. We purchase direct from JSD. The latest versions seem to be "rougher" than previous versions. We have no control over their QC.