The Winchester 1300 "Defender" pump action shotgun is a simple gun to operate. It is also fairly simple to disassemble, but a number of parts are spring-loaded and should be removed carefully. If you have a clean table or cloth on the floor and a few basic tools, you are ready to begin.
Unload the shotgun. Make sure there are no shells in the magazine or in the chamber before you disassemble your gun.
Remove the magazine cap. With the action closed and the safety on, unscrew and remove the cap at the front of the magazine tube, beneath the barrel.
Pull the barrel forward, out of the gun. The barrel will easily pull away from the rest of the firearm once the cap is removed. Screw the cap back onto the magazine tube when the barrel has been set aside.
Trigger Guard Removal
Push out the trigger guard pin. With the gun lying so that the trigger guard is facing you, use a non-marking punch to push the guard pin from your right to your left, through the trigger guard and out the side with the ejector port. Use a non-marking punch that is smaller than the pin.
Pull the pin out fully. Once you can grab the pin, pull it out of its hole and set it aside.
Pull the trigger guard group out of the shotgun. Grab the trigger guard with two fingers and pull it out and back to remove it and set it aside.
Disassemble the slide and breech bolt
Remove the magazine cap. Unscrew the magazine cap which you first removed in Section 1.
Slide the pump (or slide) and bolt assemblies forward. If you have a 12 gauge model, then without removing anything else, slide both the pump assembly and bolt assembly forward, removing the bolt (which is the "guts" of the shotgun just rearward of the chamber) through the front opening where the barrel used to be. The pump is located along the magazine tube, and it will simply slide forward and off the tube.
Detach the slide arms from the bridge if you have a 20 gauge instead of a 12 gauge model, and extract the bolt through the bottom opening because it will not slide out the barrel opening.
Remove the firing pin
Press forward on the firing pin with your finger. Hold the bolt in your hand, or place it on a flat surface. Turn the bolt so the flat side faces you and put pressure on the spring-loaded firing pin with your finger.
Detach the slide arm bridge. While keeping pressure on the pin with one hand, move the bridge forward slightly and lift up to disengage the curved tongue from the firing pin groove. With this done, your firing pin can be removed. Do so with care because the pin is spring-loaded and will fly out of your gun if you release the pressure too fast.
Disassembly is complete. Winchester does not recommend or approve any disassembly beyond this point, nor is any needed for cleaning and basic modifications. Further disassembly will also void any warranty you may have on your firearm.
Items you will need
- Small non-marking punch
- Place gun parts in places where you can easily identify them when reassembling your firearm.
- Always follow universal gun safety procedures.