I read a couple of forum posts the other day where the topic was whether to clean the barrel of a rimfire rifle. I thought I was familiar with most of the old wive's tales out there but this is the first I've heard of this one.
Some of the arguments provided were since rim fire rifles don't usually use copper bullets being pushed through the barrel at over 3000 feet per second like center fires, copper fouling shouldn't be a problem.
There was also an argument that modern rim fire powders are now so clean burning that one shot blows the residue left in the barrel out and replaces it with it's own residue thereby causing a consistent build up which results in accuracy.
Well I am here to say that after a lifetime of shooting rim fire rifles, I do not subscribe to any of the arguments above. Here is the quick answer.
Yes, you should clean your rimfire barrel at least every 300 - 400 shots to prevent a loss of accuracy due to lead, copper, and carbon residue build up in the barrel, chamber, bolt face, feed ramp, etc.
The number of rounds could be different for your rifle but the numbers above will be close. Too long without a complete cleaning and functionality, as well as accuracy will suffer. What happens in your rim fire barrel as you shoot? In reality, every shot you put down your barrel leaves some kind of deposit behind. Whether it is lead, copper jacket, burned or unburned powder, rim fire ammunition is the dirtiest out there. There are waxy chemicals used on these bullets to help with feeding issues that combine with the other components mentioned above to create a true mess. As these deposits are left in rifle grooves, chamber cuts, bolt face or on top of barrel lands, they begin to change the behavior of the bullet both down the remainder of the barrel and once it exits. The more you shoot the more these deposits accumulate. You will know when your rifle has reached it's maximum number of shots for the particular ammo you are shooting when groups begin to open up quickly. This is an indicator of excessive build up in both the chamber and the barrel. The objective is to clean before this happens. By this time a heavier and more intense cleaning job will be necessary than if the rifle had been cleaned before reaching this point of accuracy loss. After cleaning, how many shots to get back on target? This is a pretty broad question. This best answer I can give based on experience is it depends on your rifle, barrel design, ammo type and characteristics, and many other variables. Simple answer - most of the time, one to ten shots. Will all of this cleaning wear my barrel out faster? If your barrel is made from metal soft enough to be worn by moving a brass or plastic brush on the end of a plastic rod through it a few times, you need a new rifle anyway. Seriously, cleaning your rifle normally is not going to wear it out. Maybe if you ran the brush through 3 or 400,000 times or you used a drill to spin it for hours inside the barrel, you might have a problem. With this said, one thing you should be careful of is using any type of jag with a sharp end or jointed side. Depending on what material the jag is made of will determine if it will hurt or scratch the rifling in the barrel, but it's best to avoid this situation. Avoid especially dragging a mis-jointed cleaning rod attachment back and forth over the crowned edge of the rifling. That is right at the muzzle end. This section of the barrel is like the finger tips for a baseball pitcher. This is the last place the barrel touches the bullet and we want this area to be sharp and like new. Although soft metal metal on both the jag and the rod probably doesn't effect the barrel, the very crown tip of the barrel is like a baseball pitcher's finger tips. This is where the accuracy comes from. It's best not to mess with it. To avoid this just barely stick the jag or brush out of the muzzle end of the barrel, remove the patch then withdraw before a jointed section can touch it. Don't be afraid to clean your barrels and chambers with a good brush by hand. Do it before you begin to lose accuracy. Relax and enjoy shooting your rifle
What results should you expect after cleaning?
Expect your barrel to be back to a normal level of fouling within 1 to 10 shots after cleaning. The fouling will re establish itself minus excessive lead, copper, or charred material build up. This is a good place for the barrel to be from an accuracy standpoint.
Don't clean in the middle of a match or hunt. Slow degradation of accuracy is always better than a sudden shift in point of impact. Every rifle handles ammo and cleanings differently.
After cleaning, when shooting the same ammunition, after your fouling shot you should see group consistency improve and point of impact return.
How to clean your rim fire barrel properly
There are as many recommendations on how to properly clean a rimfire barrel as there are shooters to give them. I have taken what I have learned from good shooters I know, combine that knowledge with a little bit of my own and come up with the procedure below.
It's really very simple and just common sense. Doing this has served me well over the last 30 years.
Remember the procedure will preserve your rimfire accuracy if done every 300-400 shots or before accuracy begins to significantly deteriorate. Nothing good is happening in your chamber, throat, or barrel when fouling is excessive.
One last thing before the procedure. I have used Hoppe's bore cleaner and lubricating oil for many years. The quality of these products speak for themselves when you look at the condition of my rifle bores. They are a still in pristine condition after a whole lot of shooting.
My cleaning procedure is really very simple. I soak a brass barrel brush in Hoppe's and from the chamber push it through the barrel once, then pull it back. Soak the brass brush again and repeat. Now let the barrel sit for 2 minutes to soften up hard residue.
Then make 2 more passes with a dry brass brush. Push clean patches through once and remove them at the muzzle end until they are clean. Then one last patch with lubricant.
If you know fouling is excessive, or you can't get a clean path with the solvent, start with the CLP 4 or the Gilmour foam (above) and give it a few minutes to set in the barrel and loosen up the hard stuff.
Don't leave this stuff in there too long as both items are very strong and might start eating on the barrel metal. The goal is to take all surfaces down to bare metal by removing the hard deposits. The action of these chemicals can be stopped with a patch or two of Hoppe's solvent.
Before you shoot the rifle the next time run clean patches through the barrel to remove remnants of the lubricant.
I can honestly say, this procedure will allow your rifle barrels to provide many years of accurate service and fun for you. It's worked for me for over 30 years.
Don't pay attention to old wives tales other than for entertainment. Use common sense when caring for your rifles and they will provide many years of use to you and your family.