We were swapping out units: I was getting a newer take-home unit from one of the other guys. He was getting another unit assigned to him by the chief in our small-town police department.

We had just been issued brand new riot guns, and I was pleased when I recommended to the chief we get Remington 870 12-gauge pumps, and he agreed.

They came to us brand-new in the box, black injection-molded stocks and pump forearms, extended magazine tubes, chambered for 2¾- or 3-inch shells.

They were "Parkerized" - a dark grey and coarse finish that is extremely wear resistant and used by the U.S. military for many decades.

We were also issued several boxes each of 12-pellet 00 buckshot and rifled slugs.

I left mine in the office evidence room since I would be getting the unit in about 2 weeks time. Several of the units have locking racks in the front, and the other officers proudly installed their handsome new guns. The unit I was to receive didn't have a locking rack in it, and that officer locked his gun in the box in the trunk of the car, according to office policy.

Two weeks later, as we were transferring the papers, tablets, forms and all the detritus that goes into the front seat and trunk of a working police car, we pulled my buddy's boxed Remington out of the trunk to transfer it to his new unit.

When he opened the cardboard box, we both were stunned to see large scabs of rust in several places on the receiver and barrel of the shotgun. The formed styrofoam carrier in the box was stained rust brown in several places when he lifted the gun, and the entire gun carried an almost invisible patina of rust.

We checked the carpet of the trunk suspecting leaks, but the trunk was dry. Obviously, in the hot and cold changes of a Louisiana winter, the humidity in the trunk was way above normal, and the gun's surface reacted accordingly.

He immediately wiped the firearm's entire surface with gun oil, cleaning the scale from the receiver and barrel, and leaving a coat of oil on the gun.

I placed my gun in the box and trunk exactly the same way, pulled it out of the trunk after three days of dry weather to oil it, and found a thin patina of rust starting on the gun, and a couple of light rust spots.

Taking #0000 steel wool and coating the rust spots with Smith & Wesson Firearms Protectant & Lubricant, I lightly scrubbed the rust spots with the oil-soaked wool, and removed the scale, leaving almost no noticeable marks. I hate to think what the gun would have looked like if I had procrastinated for a week.

When we told the chief what had happened, he commented, "I didn't think Parkerized guns would rust."

This is a common misconception with guns that have been treated with an electro-chemical coating of zinc, manganese or iron. It has served the military well for many years, and many people believe it is a superior finish to "blueing" or other types of finish methods.

Actually, Parkerizing is a phosphate coating that soaks up the grease or protective oils placed on the gun to inhibit rust, and keeps it on the gun - thus the oil or grease is not so easily wiped or washed off the finish, and protects the steel much better. Without the oil or grease, a Parkerized finish will rust faster than more common (and advanced) finishes.

A friend, a gun blogger and writer of some repute, tells how he took a Parkerized 1911 and coated it in clear Vaseline, then heated it in his oven for an extended period of time. This opened the pores of the steel and let the Vaseline soak into the steel, protected by the Parkerized finish. (Visit xavierthoughts.blogspot.com/2007/02/parkerizing-truth-vs-tales.html.)

He admitted it was quite nasty for some time while the gun leached Vaseline, but once he got the excess off, the gun has retained the qualities of the old military arms that were Parkerized and came shipped in a grease known as cosmoline.

Those guns would resist rust in most all conditions - because the Parkerized steel was impregnated with grease. Many a GI cursed many a non-com when he had to clean newly-arrived rifles wrapped in wax paper with a heavy cosmoline coating. The stuff was like trying to clean off axle grease - thus the protective qualities that lasted nearly forever.

He said once he got past the leaching process, he never had to worry about his gun again, putting it in holsters after use with sweaty hands, on hot, humid Louisiana days, in all sorts of weather conditions, and the gun never rusted.

That's a bit extreme - but us gun nuts go to extremes sometimes in the practice of our avocation. All that's really necessary with a Parkerized finish is to coat it with a good gun oil. The finish will soak up the oil to the point you will not be able to feel the oil as in a smooth finish, but it will attach to the steel of the gun much more efficiently.

All of this got me to thinking it is time again to give the guns a good cleaning, and put them away for a while - and what consists of a good cleaning for a lot of folks.

First off, NO WD-40!

We talk to countless gunsmiths in the course of our CCW classes, and to a man, they say do not put WD-40 on your guns. Some jokingly say don't even have it in the same room with your guns, so you won't be tempted.

A gun coated with WD-40 instead of a good oil will rust - in an amazingly quick time. Yet duck hunters and other outdoorsmen who shoot in wet environments will spray their guns down with WD-40 and forget about them.

And days later, they will be shocked at the amount of surface rust they find on their fine firearms.

An excellent start to cleaning any firearm is to spray it down with a cleanser that removes oils, grease, burned powders, etc. When I was in the Army, I used to clean my rifle barrel and all its parts first with cigarette lighter fluid. Once the fluid washed the steel clean, it evaporated, leaving a clean, unprotected surface. I would then wipe everything down with an oily rag, and run a lightly oiled patch through the bore.

Nowadays, aerosol cans from the gun stores do just that for you - with the ease of a powerful stream of cleanser shooting out of the can, knocking the filth, oils and greases off the surface of your guns. These products are extremely effective, and costly.

An excellent substitute is plain automotive brake parts cleaner, inexpensively obtained at any auto parts counter (and it comes in a bigger can).

It works exactly the same at considerably less cost. Be warned - DO NOT use carburetor cleaners for this job. These petroleum distillates will eat finishes on wooden grips and stocks, and I have seen it melt plastic handgun grips.

Once you have cleaned the burnt powder and accumulated gunk trapped with the old grease and oils on the gun, wipe it down with an oily rag soaked with a good firearms protectant/lubricant, run a lightly-oiled rag through the bore and put your baby to rest for the long sleep until next hunting season.