fosscad-repo-frozen/Rifles/AR-15_FOSSCAD_Israel_75rd_Drum_Magazine-nils

AR-15 75 round 5.56mm Drum Magazine (The Israel)

Author

nils

License

GPL v3.0

Version

0.1

Description

A 75 round drum based off of the classic AKM/RPK drum, adapted to hold the 5.56mm cartridge. This CAD contains parts inspired by the Defense Distributed Cuomo Magazine.

Construction

WARNING This is an alpha-quality release. A working drum will require significant manual adjustment. All parts should be printed at 100% infill.

Assembly

0. View the exploded view for reference
1. Place the torsion spring inside the inner circle of the large drum body. The spring's outer key should align with a notch in the center ring of the body. The spring should be inserted into the body in the clockwise orientation.
2. Feed the guide rod (blue) through the hole in the front of the drum body, while aligning the small slot with the center loop of the torsion spring.
3. Place the torsion spring cap (red) over said spring. It should fit snugly.
4. Place the key spring around the small cylindrical arm of the key (green), then place the key spring-first into the center hole of the guide rod. The arms of the key slide into the slots of the guide rod.
5. Place the nubs of the follower (purple) in the holes of the spindle arm.
6. Align the notch in the center of the spindle (yellow) with the arms of the key, then push the spindle until the guide rod emerges through.
7. Slide the magazine adapter (teal) into the slot at the top of the drum body.
8. Align the tabs on the rear body shell with the notches on the front body shell and join the two.

Operation

0. The procedure for loading the drum is very similar to that of other drums.
1. Remove the rear cover
2. Push the key down to remove tension on the spindle
3. While holding the key down, rotate the spindle clockwise until the follower prevents further movement
4. Insert ammunition into the available spaces
5. Replace the rear cover, taking care to properly align the winder with the top of the key
6. Turn the winder counter-clockwise until sufficient tension has been achieved

TODO

• Adapt drum to accept readily-available torque springs
• Adjust for tolerances/reliability
• Adapt for better printability
• Fix follower
• Adjust drum body tabs