AR15 .22LR magazine (10 rnds) for Catch22(v2)
Print Profile(1)

Description
AR15 .22LR conversion magazine (10 rounds) for Catch22 & Catch22v2
This custom-designed magazine is specifically engineered to work with AR15 .22LR conversion uppers in combination with the Catch22 bolt catch replacement or the Catch22v2 bolt catch addon devices. It enables proper bolt catch engagement after the last round is fired, solving the common issue of the bolt catch not functioning with standard magazines on .22 conversion uppers such as the Nordic upper.
Important:
This magazine is NOT compatible with standard .223 AR15 uppers and must only be used in conjunction with a .22LR conversion upper fitted with Catch22 or Catch22v2 components.
Features
- Bolt Catch Compatibility
The magazine design aligns precisely with the Catch22 and Catch22v2 bolt catch, ensuring reliable bolt hold-open after the last round. - Modular Construction
The magazine consists of a main body and replaceable feed lips. The feed lips form the critical top portion affecting feeding reliability and wear. - Material Recommendations
- Main body: Printable in PETG for good toughness and ease of printing.
- Feed lips: It can be printed in PETG, but i would recommend to print in polycarbonate for extra durability and longevity. The separate feed lip design allows easy replacement without discarding the entire magazine.
- Durability & Maintenance
Replaceable feed lips extend the service life of the magazine by allowing quick swapping when worn out. - Unique Design
The magazine has no bottom opening; the spring and follower are inserted from the top. This makes it easy to print and assemble.
Hardware Requirements
- 4 × M3 heated inserts (5mm diameter, 4mm height)
- 4 × DIN 912 M3 cylindrical screws (8mm length)
- 1 × Trapezoidal spring, size 0.8 × 5.5 × 21 × 210 mm (commonly available on AliExpress)
Assembly Instructions and Safety Warning
Important Safety Warning:
The spring is under tension when assembled. Exercise extreme caution during assembly and disassembly. Always wear eye protection to avoid injury.
Follower Components:
The follower consists of two parts:
- The follower body itself
- A spring guide that interfaces with the spring
Assembly Steps:
- After removing the support structure in the upper part of the follower, apply a few drops of a strong adhesive (recommended: Pattex Extreme Repair) into the guide opening. Use just enough glue — avoid excess that may interfere with assembly. Wipe off any excess glue carefully.
- Insert the spring guide into the glued opening and let it dry thoroughly overnight.
- Once the glue has dried and the heated inserts are installed in the magazine body, connect the trapezoidal spring to the follower — it should click into place securely.
- Insert the assembled follower and spring into the magazine body from the top.
- Place the upper part with the feeding lips onto the follower.
- Carefully compress the spring and push the upper part down into the magazine body until it sits flush.
- Align the upper part properly with the magazine body and secure it by screwing in the four M3 screws.
- Test the follower movement by pushing it down; it should move smoothly inside the body.
- If the follower does not move smoothly, loosen the screws and check the alignment again before retightening.
- If movement is still not smooth, carefully disassemble the magazine and use fine sandpaper or a small file to smooth any sharp edges or transitional corners between the magazine body and the upper feeding lips.
- Optional: smooth the ramp of the follower using sandpaper. Printed with the profile provided the steps are smooth enough though for proper function.
Usage Notes
- Designed exclusively for .22LR AR15 conversion uppers with Catch22 or Catch22v2 bolt catch.
- Not suitable for standard .223/5.56 uppers.
License
You shall not share, sub-license, sell, rent, host, transfer, or distribute in any way the digital or 3D printed versions of this object, nor any other derivative work of this object in its digital or physical format (including - but not limited to - remixes of this object, and hosting on other digital platforms). The objects may not be used without permission in any way whatsoever in which you charge money, or collect fees.








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