Installing a Magazine extension on a 870, 1100 Special Field, or 1187 Shotgun
Lean how to install and properly remove the crimp in the magazine tube to increase the capacity of your Remington 870, 1187 or 1100 Special Field.
WARNING: Never attempt to disassemble or reassemble a firearm unless you are absolutely certain that it is empty and unloaded. Visually inspect the chamber, the magazine and firing mechanism to be absolutely certain that no ammunition remains in the firearm. Disassembly and reassembly should follow the manufacturer’s instructions.