The fouled barrel

[Wile E Coyote]

I would like to ask, why is it that a fouled barrel tends to shoot a cold bore shot more accurately whereas a clean barrel apparently throws the first one? I have always assumed that first one was just me not settling down properly before applying a good squeeze to break the shot. With this in mind, I've lately concentrated on taking plenty of time and executing a few dry fires before actually shooting. Briefly, here's what took place over the last few days to get me thinking about the impact of a fouled barrel on first shot accuracy.

Last Thursday I had the opportunity to shoot a few rounds in the afternoon at exactly 300y on steel. A chip shot for my 7RM. The first round is almost always 2o'clock from POA by about 1/4 minute out of a clean, cold barrel. Several more were dead on the POA; inside 1/4MOA. Satisfied and out of time, I packed up and headed home where other calamities awaited and the gun was put away without cleaning. This is something that is highly unusual for me; Benchrest mentality perhaps.

On Saturday afternoon I was able to shoot again with the dirty barrel. This time the steel ranged at 480y; same rifle and batch of ammo. Calculated the dope and this time the first round on steel was dead on as were several more rounds. We went on to reduce the woodchuck population in the farmer's fields until the original 20 rounds were expended. Several shots were over 700y and all were dead on accurate.

Saturday's performance was exceptional considering that I've had little time to practice or shoot anything this summer. Nothing has changed with my equipment, same rifle, scope, bipod and blocks, reload recipe, ECT. The only thing "mechanical" that was different was the fouled bore that I still haven't cleaned. While I consider myself a good shot, I'm not that good.
Why does the fouled bore apparently make a difference for the better? Logically one would think the clean bore would be the most accurate and accuracy would diminish as more rounds are fired.

Of those of you who may leave your rifle 'fouled,' how often do you clean the bore? Is there something more to this or should I just leave it alone and fire a fouler before shooting a clean barrel?

Anyone's thoughts are appreciated. Thank you.

 

[RTK]

The powder and copper fouling smooth out all the minute peaks and valleys in your bore. I have had guns that take quite a few rounds before they will even start to group well after a good cleaning..

Over the years I have learned to clean less and less. I usually will try to patch out the powder fouling with a few patches after shooting but really don't get very aggressive any more, especially for the copper fouling. If I am not going to shoot for a long time I do a thorough cleaning then patch with kroil and oil before putting her up. I know guys that only clean when accuracy drops off, and that is very rarely, maybe after a few hundred shots.

 

[JeffP40]

I think you are too worried about cleaning. Most guys do not clean very often. My hot-rod 6.5 gets it after maybe 2-300 rounds. It shoots great throughout the cycle. Some (few, from what I have seen) barrels don't like to be dirty. My cousin has a Cooper in 6-284 with a 14" twist that won't shoot after about 25 rounds. My daughters' .257 like to be clean. Most of my other ones don't care that much. Keep shooting until it stops grouping, then clean. easy and a lot less work. Don't sweat the small stuff.

 

[1SevenZero]

I know there are guys out there that will use a Carbon specific solvent to clean the firearm. They'll only use a copper solvent after accuracy begins to drop, or after a predetermined amount of rounds.

The theory as I understand it is the carbon is what leads to the wear and tear on the barrel, not the copper. So by doing the above they prevent the wear and tear, but maintain the fouled barrel accuracy.

I clean mine after each range day and use a carbon/copper solvent. I've zeroed my scope for a clean cold bore shot. My CCB point of impact is the same as its DCB point of impact.

 

[Broz]

My theory on this subject after some of my own testing and development of my own system is this. All my cold bore accuracy problems were caused by my old cleaning method. It included a oily patch and then a few dry ones after cleaning to protect the barrel from rust. I now believe that the oil was my main problem. My new method is using BoreTech cleaning products that protect the barrel for storage and no oil is needed. I simply dry the barrel out before shootint with 4 or 5 dry patched. My first round clean bore accuracy is as good as any shot after. I have proven this with all my custom barreled long range rigs. The 300 win and 338 LM will hold 1/2 moa accuracy from point of aim to 1400 yards. Works for me.

Jeff

 

[blipelt]

Jeff could you go into detail on your cleaning methods please pm or post. I haven't gotten any boretech yet. I still use the water based/oil based ammonia and finish it off with Iosso. I know accuracy goes hand in hand with the maintance of your barrel. My goal is to clean as good as I can with as less runs/patches down the barrel.

Brent

 

[Mike 338]

Oil leaves a uniform film the length of the barrel. This effectively tightens up the barrel dimensions until it's pushed out and burned off. I suppose some of that oil is hanging off the front of the bullet at it leaves the barrel too. After that, the fouling inside is more or less uniform from shot to shot. In an engine, pistons/rings ride on a film of oil, not against the cylinder wall.

 

[Broz]

Jeff could you go into detail on your cleaning methods please pm or post. I haven't gotten any boretech yet. I still use the water based/oil based ammonia and finish it off with Iosso. I know accuracy goes hand in hand with the maintance of your barrel. My goal is to clean as good as I can with as less runs/patches down the barrel.

Brent

Pretty simple Brent. Start with 4 wet patches of BoreTech Eliminator. Eliminator gets copper as well as carbon. This will be evident by the first patches being black then it will change to blue getting copper. After the 4 wets, let soak 10 minutes. Then two more wets, and soak 10 minuts. Then 2 more wets and let soak 10 minutes. Continue this routine untill you can run 4 patches after the soak with no blue on any patches. Do not rush it, it will take a while. If really fouled you can use a good fitting nylon brush and soak it well. I give it 20 strokes then go back to patches. After the barrel is clean, run 5 patches through to dry it. Then swab out the chamber, clean the bolt and lube the bolt contact areas, and it is ready to shoot. I recommend nickel pated jags so you know where the blue is coming from and keeping the muzzle down t let the excess cleaner exit the barrel. Also clean the muzzle brake and crown as you go along so as to not pick up blue there. Always use a well fitting bore guide and a rag or paper towel to keep cleaner from getting into the trigger area.


With my back ground in racing and building blown nitro engines I am fully aware of how oil works, especially in a high heat environment. I believe the effects of the oil takes more than one shot to burn out. This could also be dependant on oil type and how long it has been in there. My goal was to develop a cleaning method where I could clean and go hunt with confidence in my first shot from a clean rifle right out of the safe. I am pleased with my method and the products I use. With me it is all about hunting, and one shot is all I hope to use. So this is why I worked to get it.

Jeff

 

[extreme]

my 338 lapua needs 3 fouled shots after a good cleaning to bring it back to dead on at 200 yards. The first 3 shots will be 1.5 inches to the right ,2nd shot 1 inch 3rd shot 1/2 inch and
from that point they are all in the center ...i never touch the adjustments ,,it will do this every time out of a cold bore cleaned barrel

 

[blipelt]

Just out of curiousity anyone ever look after cleaning with a borescope to see how well they did?

Brent

 

[Wile E Coyote]

Brent, Yes I have looked at the bore on 2 occasions when a scope was available in tha past year or so.

The first instance was with a Savage 99, .308 when I used a Tubb final finish kit on it. This was also the first time I had viewed a chanber and bore with a scope. I had bought the rifle about 25 years ago and it sat in the back of the closet until I moved in 2006. That's when I started to use it every deer season. It would shoot somewhere between 1 and 2 MOA off a bag with factory ammo. In the field it was more like 3 or 4 MOA off a log or rock ect. I thought it could be better and was about to send it off to the gunsmith for a checkup, re-crown, or a new barrel. Someone suggested the Tubb kit and not having much to lose, I sent for one to try. To see the improvement in the barrel of this gun was dramatic. despite an initial cleaning with Hoppes #9, with patches, a bronze brush and a muzzle guide, one could still see a lot of dirt and debris in the corners of the grooves. After each of the 5 steps in the kit we looked again and could see improvement each time. Today the 99 shoots about 1 MOA or so in the field and less on a bench. And that's with the original factory creepy, crawley trigger that has about 3/4" of sear engagement and about 1/2 ton of pull weight.

Earlier this past spring The same bore scope was used to look in the bore of my 7mmRM with a Hart barrel. This is the rifle I was referring to in the original post of this thread and, if it's important, as of this moment, the barrel has 267 rounds through it. The barrel had been cleaned 2 days earlier with Hoppes #9 and patches until clean. Then one patch with a little Kroil which I dry patch out before shooting. After a dry patch, one could see a little (very little compared to the 99 above) fouling in the grooves with more near the chamber and less at the muzzle end. What did surprise me was the amount of debris in the neck and shoulder area of the chamber. Later after firing a few rounds and performing my usual cleaning it looked about the same as earlier. The bore and chamber are clean but there is a small amount of junk in the corners, nooks and crannys.

Since I'm about out of #9, I'm open to and going to try the Boretech product Broz mentioned earlier using the same regimen he outlined. Thanks Broz.

 

[Broz]

Since I'm about out of #9, I'm open to and going to try the Boretech product Broz mentioned earlier using the same regimen he outlined. Thanks Broz.

I buy BoreTech Eliminator from www.midwayusa.com Just for fun you should clean with your regular cleaner and method. Then before you shoot the rifle go back in ith the Boretech and clean again. Everyone I know that has tried this was amazed at the copper still in there. I am glad you decided to try this, and I look forward to your results. I was very happy when my first bullets were within 1 moa of point of aim even past 1000 yards and the next 2 formed a 1/2 moa group.

Jeff

 

[rick523]

Wile,
I find one thing interesting in your senerio, I just finished build on 7mm rm and it groups the exact same way with clean bore first shot high 2 oclock next shots are poa regardless of yardage. I am curious what bullets you are shooting. I am using 168vld's. I read somewhere, possibly here that vld's are bad about a flyer. All my loads are the same as I am a little anal about reloads.(68.5grs.H1000, Hornady cases, fed215m primers, I tried cci magnums but still got same results all bullets are seated to same depth, coal is 3.519 which is touching lands. I tried backing off and jumping but that didn't work.)

Anyway I found the same thing fouled barrel first shot is poa. One note I don't beleive in cleaning out copper, carbon yes, copper only after several hundred shots or when accuracy drops off. But that is just MHO.

 

[extreme]

I use boretech eliminator and when i,am done cleaning any of my rifles the last patch is snow white and dry ..after 50 years of shooting rifles costing from $500.00 dollars to $6000.00 the
thing i learned is to shoot or waste the first 2 shots before
going hunting or a serous site in job no mater what the range 100 yards or 1000 yards. There is another thread on here somewhere
close to this same thing...there where many people that posted
that they needed at least 2 fouled shots before getting serious.
Clean until your arms hurt you but most if not all rifles do the
same thing.