Update 8/15/24: MP22K kits are back in stock with freshly machined pins in hand.

This listing is for a complete parts kit, consisting of every single nut, bolt, rod, spring, bearing, pin, and laser cut part used in the process of completing or rebuilding the MP22. For a list of what is NOT included, please see below.

Please pay close attention to the options listed:

Barrel Liner Length: 100mm is standard for shorty configurations, if you are a purveyor of muzzle mufflers, choose the 120mm (+$10) or the 110mm with direct metal threads (5/8-24) (+20) I’ve also added an option for custom length liners for carbine builds. This is a great option if you don’t want to build it out as a braced pistol, or want to do a full stock. YOU MUST INCLUDE LENGTH IN YOUR ORDER NOTE IF YOU SELECT CUSTOM

Main Rod Length: By default, the main guide rod is 300mm. It will need to be cut with a grinder and cutoff wheel to 265mm and fitted into your build. For an additional $10, I can cut and grind it flat to ~265mm. Some fitting may still be required.

Brace Rod Length: Same as main rod, by default these rods are 254mm. To sit flush, they will need to be cut to ~230mm. For an additional $10 I can cut and grind flat to ~230mm. Some fitting may still be required. I’ve also added an option for no brace hardware, in case you’re printing a full stock.

Bolt Weight: By default, you receive 2oz of lead shot. You will need to melt it in a tin can with a torch and cast it into sand with the printable mold. For an additional $20 I can cast it for you.

Magazine Springs: Who doesn’t want extra magazines? $5/pc for extra springs, up to 2 extra. Need more than that?? You can find them in the store and combine to save on shipping

Parts that are NOT included in this kit:

Any plastic parts

AR FCG

AR Safety spring and Detent (for HK Style safety, kit only includes rods for push button safety)

We have worked closely with the creators of the MP22 to ensure that the parts offered in this kit are accurate, and consist of quality parts. Please note, there are discrepancies between this kit and the BOM listed in the MP22 documentation. This kit is more accurate than the BOM in the documentation. Please note, I’m not a machine shop, just a guy in my garage. You may be able to see some variances between parts. I work hard to provide a quality kit, however if something is wrong, please let me know, so I can make it right.

A few things you should know before buying this kit:

This is a hardware kit for a 3d printed gun. No plastic pieces are included, and no parts of this kit are regulated items.

Please be aware, I’m just a guy in my garage, not a full blown machine shop. If you select having the rods cut to length, please know they will be approximate, and some fitting may still be required.

The bolt weight will require fitting during installation. You will be exposed to lead. Please take adequate precautions to avoid contamination.

This kit is still in public beta. What does this mean? It’s relatively new. Only about 20 of them exist out in the wild at this point. While no issues have been reported, it doesn’t mean no issues will be found. If an issue is found, I’ll do everything I can to address it and make it right. I spent many hours over a series of weeks working directly with the creator of this kit to ensure its accuracy. You might note that there are differences between this kit, and the BOM in the read-me. This kit is more accurate than the BOM, there just hasn’t been a re-release of the MP22 with an updated readme yet.

Kits are packed and cut to order – What does that mean? I pack most of the kit ahead of time (all of the nuts bolts and springs) and when you order it, I cut your rods to length, pack the options you selected, and make all of the pins in the kit (I make these by hand in my garage). I ship all orders in the order it was received. I’m calling this out, because while I have inventory on hand for 20 kits, if 20 of you order it tonight, it will take me at least a few days to get all the pins cut and get them all shipped.

Read-me

Complete list of parts included in this kit below:

PLEASE NOTE: This is a complex build, and a lot can go wrong. Please use extreme caution while using this kit to assemble your build. Follow the instructions closely, and don’t make guesses. If something isn’t working how the instructions say, you’re probably doing it wrong. We’ve done as much as we can to simplify the building of this kit, but at the end of the day, you are assembling a gun from scratch. Please use adequate precautions, including test firing remotely from a safe distance. Please inspect all parts closely to ensure they are in spec, and if something even seems a little off, its worth a reprint. Filament is cheap, hospital bills aren’t. Don’t take shortcuts, and have fun with your new MP22

DISCLAIMER: Usage or misuse of this product may lead to injury, exposure to chemicals known to cause cancer, and even death. This item is sold with no warranties or guarantees, either express or implied. By purchasing this product, you agree to hold the seller harmless for any consequences resulting from its use. You assume all legal liability for ownership, possession, and usage, and agree to indemnify the seller accordingly. It is your responsibility to understand and adhere to the laws in your jurisdiction.

California imposes additional requirements that cannot be met by this kit. These include mandates such as 3D printed firearms being manufactured by a California Department of Justice (CA/DOJ) licensed Federal Firearms Licensee (FFL) with a serial number provided by the CA DOJ. Moreover, all new designs must incorporate microstamping capability and undergo independent safety testing to be listed on the Unsafe Handgun Act verified safe list.

This item only ships within the US. International orders and shipping addresses outside of the US will be ignored.