I was watching the Magpul Precision Rifle video today, and came across the segment where Todd Hodnett discusses clean bore vs cold bore. He mentioned something I’ve never heard of before; that he never cleans the copper fouling out of his barrel. The reasoning was (as I understand it), that in the process of zeroing, the barrel begins to strip copper from the rounds. By the time the rifle is dialed in, the optic is set to POA=POI when the barrel has fouling in it. By cleaning out that copper, the gun will shoot off POA until the copper from the fired rounds has once again settled into the rifling and the barrel returns to the condition it was in when it was zeroed. Does the same apply to an AR barrel (I figured this was a specific enough question for the technical forum.)?
I don’t see why it wouldn’t apply to an AR barrel.
Of course, I think you’re doing some pretty serious precision shooting before you can notice the difference between a “clean” and a “fouled” barrel…
It does apply to ARs but only if you are very exacting about your accuracy and actually track it. For carbine use, don’t worry about the clean bore shot.
If you are shooting for long range precision, clean the barrel when accuracy drops off. That’s it. Kind of simple but so many people don’t get that.
I’ve never cleaned the copper out of my carbine barrel and have never had accuracy issues.
That said, I was always trained to thoroughly clean my bolt-action sniper rifle any times rounds are fired through it. That included painstakingly running an endless supply of patches through the barrel to clean the copper and carbon fouling. Even then, I would see a consistent drop in my cold bore shot, almost a full MOA at 100 yds. More recently, I’ve limited the cleaning to just carbon fouling and have actually seen an improvement in my cold bore accuracy.
Cleaning just got a whole lot easier for me.
Seems to me waiting for a failure before you do preventative maintenance would be fine if you think of your rifles as toys. If you use them as tools then it might be a good plan to stay ahead of the curve.
I don’t wait for my AR to quit feeding before I replace the action spring and I sure don’t wait until I start missing targets before I take care of the bore. :rolleyes:
It takes less than 20 minutes to clean any reasonable barrel down to bare steel. Not exactly a huge chore.
The key to keeping your clean bore shot POI consistently with your fouled bore POI is to make sure your clean barrel is dry. The culprit with the AR is the gas port as solvent gets in the port and then migrates back in the bore. I find that letting a clean patch on a jag sit right at the port for a minute or so really helps with the clean bore shot.
Here is a 100yd 3 shot group with the first shot being from a clean bore.
Yes, cleaning down to bare steel must be the answer. It’s just solvent that makes bolt guns have a varying POI with cold bore as opposed to fouled. I’ll just run out and tell every 8541/8542/0317 I know that their cleaning regimens are wrong.
After all, my weapons are just toys and I’m not a death dealer from afar like you.
Accuracy drop off is gradual. No one is suggesting waiting until the rifle starts missing it’s target until the bore is cleaned. I have some rifles that accuracy doesn’t change much when the barrel is fouled. Even so, you won’t know how to stay ahead of the curve until you find out where the curve is.
It takes less than 20 minutes to clean any reasonable barrel down to bare steel. Not exactly a huge chore.
Depends on how many shots were fired before the barrel is cleaned, how aggressive the copper cutter is and condition of the bore. It also depends on the definition of “bare steel”. Clean any well used and maintained barrel with brush, rod & patch until the solvent stops removing copper then clean it with the Outer’s Foul Out kit. How much copper the Foul Out will remove from a well cleaned bore is amazing.
The key to keeping your clean bore shot POI consistently with your fouled bore POI is to make sure your clean barrel is dry. The culprit with the AR is the gas port as solvent gets in the port and then migrates back in the bore. I find that letting a clean patch on a jag sit right at the port for a minute or so really helps with the clean bore shot.
Interesting observation. For myself, it’s a simple matter of just cleaning enough to remove the carbon and some of the copper fouling
Here is a 100yd 3 shot group with the first shot being from a clean bore.
Nice tight group there! Do you notice much change in point of impact from a clean barrel compared to when it’s fouled from a number of shots? Do you see a drop off in accuracy as fouling increases?
Not sure how one cleans down to the bare steel shy of a borescope.
Owning a bore scope sure does cut down on the guessing. 
Bare steel is bare steel. No fouling anywhere in the bore as examined with a 10X bore scope.
It takes less than 10 minutes to take a decent .223/5.56 mm 16 inch barrel with 500rnds of fouling back to bare steel.
Think KG products. Think bronze (powder fouling) and nylon brushes (copper fouling) and forget about soaking. 20 minutes tops to clean the whole AR. Douche out the upper and lower with Carb and Choke cleaner, add a few drops of lube and you have a sparkling clean, reliable, and accurate carbine that you know will stack high BC bullets for 300 rnds without worry.
If you are running a RDS shooting m855 and are happy with 2 MOA then this might be over kill but if you want reliable precision then you need a cleaning schedule that includes proper bore maintenance.
If your cleaning schedule works for you that’s just dandy. I know many many competition shooters who don’t clean their barrels for the entire NRA rifle season without a drop off in accuracy. At 88 rounds per match plus practice, they go well over your minimum standard without issue.
Guy above me nailed it. I don’t have the time to play bench rest shooter games. I have shot a lot of rounds through fouled bores with no decrease in accuracy and I know for certain the cold bore shot does vary in POI compared to a fouled bore shot. To argue against it is more than a little strange but hey, maybe I should be investing my time in cleaning every range session and whipping out a bore scope.
When you say that competition shooters don’t clean their barrels until accuracy drops off. Do you mean that they don’t run any patches down the barrel at all?
You seem a little obsessed with this whole cleaning issue as it relates to precision type rifles so I check back on a few of your posts and found the following quotes from a class you took a few short months ago.
I really struggle to understand how a guy who thinks 300yds is long and has to have help to hit steel at that range is so invested in preaching to the world on cleaning schedules.
While this is the internet and we certainty all have a right to our opinion do you really feel you have any valid real world experience in reference to the OPs question?
Do you actually own a Precision AR with a magnified optic?:rolleyes:
Who exactly are these “many, many competition shooters”? What events have they won?
Do you yourself have any practical experience to relate to the OPs question or are you just repeating the opinions of others?:rolleyes:
Let’s not start with silly personal attacks. Thanks
These guys don’t clean their barrels because they don’t have to. They run expensive, very smoothly cut barrels (Hart, Shilen, etc.). The copper accumulation in these barrels is almost nil. A quick look through a bore scope at a high performance barrel bore next to an OE barrel and you’ll see the difference is amazing.
I would imagine that chrome lined bores wouldn’t catch much more, but don’t know for sure, and never really cared. I do know I was at a known distance range last week with my .mil M4 shooting silhouettes at 500 meters and watching them fall. I don’t remember the last time the bore had a good scrubbing, other than a bore snake.
OE barrels are usually roughly hewn and the rough bore surfaces catch a lot of copper, especially in new barrels.
Hey John, anytime you want to best me at shooting steel at 300 yards with a 4 MOA red dot on top of a 5.45 carbine with about 20k rounds on it (second barrel) shooting soviet surplus ammo from the 80’s, let me know. We can put it up on YouTube.
I learned a lot from this guy. I know he doesn’t have your advanced cleaning techniques but he did win the long range competition shoot at Fallujah in 2004 using an SR25.
I forgot to add that I did have a precision AR. I prefer bolt guns for precision and I sold that rifle. But, I did own one so I guess it’s ok for me to comment here…
Agreed. It’s what I and my team mates did, as well as everyone on the various teams I was on over the years. We never cleaned our weapons until the end of the shooting season…that includes shooting with the USAMU and several trips to Camp Perry.
To answer your question directly, some will and some won’t. It depends on their skill level, experience and the individual rifle.
Every barrel is a law unto itself. I’ve seen barrels lose accuracy when cleaned really good. I’ve seen barrels shoot better after they’ve been cleaned. Most modern barrels seem to shoot well somewhere in between, with just enough fouling to settle them in. I can also tell you ammunition today seems to produce less copper fouling than it did when I first started shooting.
Your cleaning schedule really must meet your needs, not mine, or anyone else’s. If your rifle opens up from 2 MOA to 8 MOA after just a couple of rounds, but you’re hitting your target every time, on demand why worry? If you must have 1/4 MOA every shot and can tell when fouling starts opening up your groups, you’ve already shot the rifle enough to know how many rounds can be fired before it must be cleaned to maintain that level of performance. Clean your rifles in a way that works for you and don’t worry what anyone else thinks about it. I knew a guy who cleaned his Glock in the dishwasher. It sounded crazy to me but it worked for him!
It should be noted that even the true bench rest disciples do not believe in squeaky clean these days. Traces of copper between relays is wanted. Less fowlers is the key.