Krag-Jorgensen rifles weren't used for long by the U.S. military, but they still marked a big step forward in rifle technology, because they were the first to use smokeless powder and the first generally issued repeating rifle. If you have a Krag in your possession, it's likely pushing 120 years old – but the instructions for disassembly are still out there.
Start by making sure your rifle is unloaded and pointing in a safe direction. Now, here's how to disassemble it:
1. Remove the Bolt
Open the bolt, pulling it all the way to the rear. Then hold the bolt handle in your right hand, using your left hand to lift up on the extractor, located right above the locking lug.
Once you've lifted the extractor about 1/8 to 1/4 inch, turn the bolt handle slightly to the left and pull it to the rear. Pull the bolt completely out.
2. Remove the Striker Assembly
Pull back on the striker knob while turning the sleeve assembly toward the left. Keep turning until the front extension of the sleeve clears its lug on the rear of the bolt body.
Restrain the spring tension by bracing a thumb against the back of the safety lever while turning the sleeve assembly. Once the sleeve has cleared the lug, remove it toward the rear.
3. Remove the Firing Pin and Striker Knob
Grip the spring firmly to restrain it, then tip the firing pin off of its doll-head mount. You can then remove the firing pin toward the front, while keeping the striker spring under control. Ease tension off of the striker spring slowly once the pin is removed.
Remove the firing pin and striker spring toward the front, and remove the striker knob and rod unit toward the rear.
4. Separate Barrel and Stock
Use a screwdriver to undo the screw in the forward band. This band is the one located between the rear hand guard and the front hand guard, and it holds the barrel and stock together. Slide the band over the end of the barrel, then unscrew the screw in the back band, located at the rear hand guard. Push the securing pin out of the band and slide the band forward, over the end of the barrel.
From there, you can remove the trigger guard screws in the forward and rear, as well as the trigger guard. Separate the stock and barrel.
5. Remove Butt Plate and Rear Sight
Use your screwdriver again to remove the butt plates, and again to unscrew the rear sight screws and remove the rear sight. You can then slide the hand guard forward, off the barrel.
7. Remove Magazine
Close the magazine gate, and use a screwdriver to lift the magazine up until it's out of its seat. Then hold the magazine gate closed and use your hand to gently tap the magazine hinge bar, before separating the gate from the receiver and removing the spring-steel magazine spring.
8. Complete Disassembly
Pivot the carrier and follower outward, then remove the carrier. Follow up by pushing the pin out of the carrier and separating it from the follower.
Next, remove the side plate screw and the plate itself. Push the trigger assembly forward and shimmy it from side to side until it clears the receiver. Then remove the cartridge ejector pin, at which point the ejector should fall out of the receiver.