By John Hackett:

Most hunters know that keeping their guns clean is important to proper function.  One of the most overlooked areas is the screw-in choke system on shotguns.  Simple maintenance on your choke tubes can save costly repairs later.

Screw-in choke tubes need to be taken out periodically to clean and lubricate the threads.  Failure to do so can lead to rust build up, making the chokes next to impossible to remove latter.  In the past I have seen choke tubes so frozen up that they were impossible to remove.  If left unchecked the rust can weaken the walls of the barrel, leading to a rupture.

Before you attempt to remove the choke tube make sure you have the proper wrench for your system.  Browning, Winchester, Berretta, for example, all use different wrenches.  The use of the improper wrench will damage the end of the choke tube and can also cause them to seize up.

With the choke tube removed, use a soft bristle brush, like a tooth brush, and a good solvent to scour the threads.  Also scour the threads inside the barrel.  Do not use anything coarse like a steel brush.  The threads on screw-in chokes are very fine and will damage quite easily.

Lubricate the now cleaned choke tube with a thin coating of good quality gun oil.  I recommend Break-Free or Rem Oil.  Both these oils protect well with a thin coat and will prevent the chokes from seizing.  There are other quality products on the market also, but I’m just partial to those two.

When reinstalling the choke tubes they should thread in easily with your fingers.  If they don’t go in easily, remove the tube and re-clean.  The wrench should only be used snug up the tube.  Over tightening will cause damage to the threads.  In extreme over tightening circumstances the inside of the choke tube will squeeze into the shotgun’s bore.  Upon firing the shot column will actually shear the tube off and ruin the end of the barrel, and possibly the shooter also.

Choke tubes should be cleaned and lubricated every time they are changed.  If you are one of the many shooters who always leave the same choke in for all your shooting, you should still remove it at least once a year for cleaning and lubrication.

Under no means should a shotgun with a screw-in choke tube system ever be fired without a tube installed.  If you do happen to get a choke tube you cannot remove easily, it is best to enlist the aide of a competent gunsmith.