Off the top of my head - some common things that cause Krag magazine cartridge-feed problems:

1. Follower-carrier assembly 'sluggish' because of filth, dried & hardened grease and crud that impairs movement.

2. Curved flat-spring that powers carrier-assembly and tensions magazine-gate is bound up with dried crud, weak, or broken.

3. Pin that hinges follower to carrier-arm has moved out of position and is dragging on receiver.

4. Wrong parts - An 1898 carrier-arm has found its way on to a model 1896 action.

5. Loose side-plate - Plate must be in contact with receiver wall and its screw should be 'snug'.

6. Dented/damaged side-plate or accumulation of dried, hardened grease on curved interior surface.

Cleaning all the surfaces of the feed-path and component parts, and some light lubrication, usually solves feed problems.

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