By Gregory J. Roman
As anyone involved in the shooting sports knows, precision rimfire is growing rapidly. The internet is full of tons of advice, good and bad, on how to perform better as a shooter. If there is one thing that my time at Vudoo has taught me, it’s that there is not much good information available on how to take care of your .22 LR barrel to get the most out of it.
There are a ton of opinions and lots of folks cleaning their high-end precision rimfire just like they clean every other gun in their safe…just because it’s what they know. I’ve gained some experience in this area and hopefully I can provide some help to those wanting to know more about the right way to clean and care for a rimfire barrel.
My opinions about rimfire rifle cleaning and care are the result of my career in the gun industry and time shooting competitively in various disciplines. Firearms have been my profession and hobby for about 22 years now. About four years ago, I discovered NRL22 and began competing with my old Sako P94S.
It wasn’t long before I also discovered Vudoo Gun Works and promptly ordered a V22. When the V22 arrived, I was officially hooked. One thing led to another over the next several months, and I ended up going to work for Vudoo where I have been for the last three years.
My time at Vudoo has allowed me to gain experience with dozens of high end rimfire rifles while giving me exposure to some great minds in the industry from barrel makers to engineers to top level shooters. The last three years have been nothing but learning every day and have been the most rewarding of my career.
It’s through this exposure that I have developed my method of barrel care that produces excellent results in all my rimfire rifles. I’ve managed to climb the ranks in NRL22 with several NRL22 match wins and high finishes in NRL22X.
It should go without saying that these are just my personal methods and opinions that will differ from others. I’m offering them because of the positive results that I’ve experienced, and I’ll do my best to explain why I do everything I do.
The rifle pictured in Figure 1 (at the top of the page) is my primary match V22. Following these methods had produced great groups on paper at 50 and 100 yards. It also produces extremely low ES and SD numbers over the chronograph which translates to extremely consistent and predictable ballistics at long range.
It’s not uncommon for this rifle to produce 1st round hits on targets at well over 400 yards. It seems like the more I shoot this rifle, the better it gets. I can’t even remember the last miss I had in a match that left me asking why it happened. If I miss, it’s my fault and not the fault of the rifle.
It should be noted that I use match grade ammo in my precision rimfire rifles. That means lead bullets at standard velocity. I do not ever shoot high velocity or bulk ammo through my precision rifles. I simply don’t want to introduce another material into my bore. With my current match rifle, I’ve only ever used SK or Lapua ammo. That means only one specific alloy of lead and one type of bullet lubricant have been through the barrel.
The first thing I usually address when discussing barrel care with Vudoo customers is what we refer to as “barrel seasoning.” .22 LR barrels do not break in like a centerfire rifle. The small cartridge and soft lead bullet do not produce enough heat and pressure to burnish and deburr the rifling.
Instead, it lays down a coating of lead and bullet lubricant in the rifling. This coating is what we refer to as seasoning. It fills in small imperfections in the bore and provides a smooth surface for the bullet to travel across.
Seasoning will start to build up in the breech end of the barrel and eventually build up all the way to the muzzle. This buildup is desired and takes at least 1,000 rounds to reach the muzzle. Figure 2 shows the rifling of a new barrel. Figure 3 shows the rifling of a well-seasoned barrel.
Many shooters including myself, have found that the best accuracy results come from a barrel with fully seasoned rifling and a clean chamber. My experience with several barrels has shown that they usually follow the same cycle of accuracy during their first few thousand rounds fired:
- They typically shoot well when they are brand new, but still leave room for improvement.
- Accuracy will fall off after 400-500 rounds and not improve until at least 1,000 rounds fired.
- The barrel will then start to become super accurate and predictable after 1,000 rounds or more have been sent through it.
When the barrel sees step two, the seasoning is only partially laid down in the barrel. The bullet will begin its travel over a smooth, lubricated, seasoned surface and then suddenly hit the unseasoned portion on its way to the muzzle.
The shooter will experience some wild velocity spikes and random flyers on the target while the barrel is only partially seasoned. The rifle will also usually produce a little slower average velocity along with larger SD and ES when partially seasoned.
The .22 LR round is also prone to producing a ring of carbon in the chamber. This carbon builds up right were the casing ends. In Figures 4 and 5 you can see the location of the ring in a cutaway.
Figure 6 shows a picture of a carbon ring example through a borescope and Figure 7 shows the same chamber after cleaning.
This carbon ring is one of the biggest detriments to accuracy of a good quality .22 LR rifle. The carbon ring is very hard and acts as a constriction that squeezes the bullet during chambering. Lead is a dead metal that has no rebound when squeezed, therefore once the lead bullet gets squeezed by the carbon ring, it will no longer engage the rifling correctly.
The carbon ring usually has some of the bullet lubricant mixed in so it will slightly soften up after being exposed to a little heat from shooting a few rounds. The bullet will be squeezed less when the carbon ring is warmed up. When a shooter calls up complaining about first round flyers, most times the cause is a carbon ring. The carbon ring will start to show noticeable effect on accuracy after only a couple hundred rounds.
Another rule of thumb is, the tighter the chamber, the greater the effect of the carbon ring. Loose chambers like a Bentz chamber may not be able to produce the best accuracy, but can go longer before seeing flyers. Tighter chambers like 52D or Vudoo Ravage will see flyers earlier, but can usually produce better accuracy with a clean chamber.
When I clean my precision .22 LR barrels, I’m specifically trying to clean the carbon ring out of the chamber. I typically clean my barrels in 200-400 round intervals to minimize the carbon ring effect.
Cleaning a precision rifle barrel requires the correct tools. In my Vudoo cleaning kit I’ve assembled the following: a rifle specific bore guide, a good quality and correct caliber cleaning rod, a correct caliber jag, a .22 bore mop, a .22 nylon bore brush, correct caliber cleaning patches, Bore Tech C4 Carbon Remover, and a borescope.
Bore Tech makes the Vudoo bore guides for us along with a .22 rimfire-specific rod and jag that are slightly smaller than a typical .223 rod. The reason for the small size is to allow space to run a rod through without dragging on the ejector and damaging the rod.
I only use a brush in my bore if it’s exceptionally dirty. I do not recommend a bronze brush because it will be too harsh on the “seasoning” we addressed earlier.
I’ve been asked about running a jag and patches versus felt pellets. I subscribe to patches over a properly sized jag. I feel that this better prevents any metal of the jag from scraping the bore with a lot of pressure behind it. During insertion, the metal jag will have patch material between it and the bore all the way around when I’m pushing hardest on the rod. With felt pellets, I fear that having the pellet improperly placed off-center on the rod will result in the metal jag being pushed hard against the bore.
Let’s dive into the process.
My first step is to liberally apply some of the C4 solution to the .22 mop and insert it into the chamber about an inch to inch and half. I let the wet mop sit in the chamber for about 10 minutes, longer if it’s been more than a few hundred rounds since last cleaning. I use a short pistol rod attached to the mop for this step so I can rest it on the stock and not bend the mop. The point of this step is to let the chemical do the work. The C4 cleaner will attack the carbon buildup in the chamber, but the formula does not do anything to remove the lead and lubricant we desire in the rifling.
While the chamber is soaking, it’s a good time to focus on cleaning the outside of the rifle. I pay close attention to the muzzle at this point, because if I push anything into the bore during cleaning, it will be pushed back out in the next step. I will also use this time to clean the bolt.
After some soaking time I’ll rotate the mop in the chamber a few turns before removing it. This will wipe away the carbon that was just loosened by the C4. If the rifle has had thousands of rounds through since the last proper carbon ring cleaning I may use a brush at this point. I’ll insert the nylon brush an inch to inch and half and then spin it in the chamber to scrub the carbon ring. I do not run the brush through the whole barrel.
My next step is to run a patch soaked in C4 through the entire barrel. This wet patch will pick up any loose particles of debris and also make the following dry patches slide easily through the bore. I follow this up with four to five dry patches through the entire barrel.
My last step is to inspect the bore with a bore scope. I’m mainly looking for any remaining signs of a carbon ring in the chamber. If there is any carbon still present in the chamber, I’ll start from scratch and repeat the barrel cleaning process.
I’ve found that my rifles are extremely predictable using this method. They will usually foul in and shoot accurately in less than five rounds after cleaning. Over the last several matches, most of the ammo I shoot during the sight in period is to warm me up as a shooter rather than sight in and gather dope on the rifle. When I keep the cleaning intervals to under 400 rounds or about every other outing, the rifle comes clean with ease.
One thing I get asked about regularly is oiling the bore. Rust prevention is the only reason I would ever even think about oiling the bore of a precision rimfire. I live in the dry desert of southern Utah and do not have any issues with rust. In other words, I do not oil the bore.
In my mind, it’s just another material being introduced to the bore that will become a variable to accuracy. Oil will change velocity and will burn off over several rounds down fired. This means velocity will change a little with each round as it burns off.
We get a lot of questions about Bore Tech Rimfire Blend at Vudoo. I used to use it a lot, until I discovered the real theory behind C4. Rimfire blend will attack everything in the bore including lead, bullet lube and carbon. When we completed my previous match rifle, I started cleaning from the beginning with Rimfire Blend. The result was a rifle that shot well when new, but accuracy diminished and never came back.
When I built my current match rifle pictured above, I decided to run an experiment and clean with nothing but C4 until accuracy started to fall off. The rifle has over a year of matches and practice on it and about 5000 rounds through it. Accuracy has only continued to get better.
To date, the only chemical that’s been through the bore is Bore Tech C4. I’ve started to use C4 exclusively on my older match rifle, and accuracy has returned. If any of these guns start to see a consistent drop in accuracy, I’ll break out the Rimfire Blend, clean everything out of the barrel and start the seasoning process over from scratch.
In the end the solution is simple. Keep the good fouling in the rifling, remove the bad fouling in the chamber.
Many precision rimfire shooters understand that different lots of ammo produce different performance out of their rifles. Lapua and Eley both offer lot testing services.
For those wanting to take advantage of this service, I would strongly advise waiting until you have at least 1,000 rounds through your barrel first to fully season it in. If you tested the rifle when it was new, chances are that it will like a different lot of ammo when it is fully seasoned. I would also advise that you make sure the carbon ring has been cleaned out before testing.
Any time I’ve tested, I usually give the rifle a good cleaning as prescribed above and then run a couple magazines through it to lightly foul it up. This would simulate my match conditions after sighting in.
If you don’t have experience using a bore scope, I would caution that some things in the bore may look disturbing through the scope. Small pieces of hair or fuzz can look like cracks and flecks of debris can look like pits. I’ve received many calls and even had a few rifles sent back for barrel imperfections that cleaned right out.
It should also be noted that rimfire priming compound contains silica that does do a little sand blasting to the bore. Figure 8 shows the effect of the silica on the bore. This is perfectly normal and nothing to worry about.
The comments I’ve read online and received over the phone at Vudoo tell me this is an area full of very strong opinions. .22LR is a different animal and we all still have lots to learn. If you have different methods that work for you then I encourage you to continue with them.
This article is an explanation of why I choose to use my methods to hopefully help those who are struggling. I’m sure my process will change some in the future, but this has worked for me and it has worked for countless customers who have called Vudoo and tried this out after we talked.
The result is the capability of my rifle being the furthest thing from my mind on match day which allows me to focus on the biggest obstacle to accuracy and a match win…the shooter.
Gregory J. Roman is Director of Compliance and Logistics for Vudoo Gun Works.