Clean barrel vs Fouled barrel accuracy

Collins

New Member
Feb 8, 2016
32
0
Green Bay, WI
I'd like some opinions on an issue I'm having. I'm shooting a Thompson Encore 270 with 130 gr. Barnes. with a Burris Signature scope. The gun was zeroed at 200 yards a month ago. I then took it home, cleaned it, and ran a wet patch of Hoppes down the barrel and put it away. Last weekend I took it out, back at 200 yards, and the first two shots were 2 inches apart, but 24" high. No joke. Without touching the scope, I took two more shots, again 2 inches apart, but about 10" high. I then took four more shots without touching the scope,and they were all right where they need to be. I've never noticed such a difference when shooting a cleaned barrel, but it appears that it took those first 4 shots to "foul" the barrel, and then it was fine. I have not cleaned it since, and will shoot it "dirty" again this weekend to find out for sure.
 

Ikeepitcold

Administrator
Staff member
Feb 22, 2011
10,018
1,603
Reno Nv
I know for, rifle most long range shooters will begin to shoot or hunt with fouled barrels. They will clean the crap out of the barrel then shoot 5 rounds to foul.
 
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Work2hunt

Veteran member
Mar 2, 2013
1,366
11
St. Louis, MO
I've never heard a gun being 24 inches off with a clean barrel, but I know my 2 main rifles like a dirty barrel. After I clean I will shoot 2 or 3 rounds to dirty it up.
 

tdub24

Veteran member
Dec 15, 2011
1,331
557
Carlin, NV
Once I know what rifle tag I have drawn, I will take that rifle to the range and sight it in to my preferences. At season's end, I give it a thorough cleaning. If the next year that is the rifle needed, then I go and check my sights. So far, they have been right where I left them so no adjustments needed. I personally haven't had any issues with any of my rifles shooting differently with a clean or fouled bore with stock ammo. But my cousin reloads his own ammo and his rifle is extremely inaccurate when clean. Could reloading be part of the problem?
 

Horsenhike

Very Active Member
Nov 11, 2015
668
0
Eastern SD
When you say you cleaned it do you mean you used solvent to remove all traces of copper fouling? If so that is going to have a serious impact on poi. Most long range shooters do not scrub their bores until accuracy begins to drop off. Or so I am told. We never scrub our bores, just a patch to brush out debris after hunting in dirty conditions.
 

Tim McCoy

Veteran member
Dec 15, 2014
1,855
4
Oregon
I have a couple rifles that take 2-5 shots to settle in after a cleaning and de coppering, one I sold took about 20 rounds. Just a regular cleaning with a carbon solvent, 5-10 patches, not so much of an issue. But nothing 24" off, more like 3-4" at 200 yards for 1-3 shots.

I have several rifles up into the 250-300 round count, no cleaning, with no accuracy loss at all, no hi volume hot barrel shooting however. All they may get is 1-2 patches with light oil before being put away, if even that. You'll find some interesting round counts without cleaning on some of the sniper/military sites.

One theory is some copper is needed in some barrels, to fill in flaws? No idea. What I do know is every rifle is different, and improper cleaning can do major damage, especially to the crown.

I have moved towards only cleaning hunting rifles if accuracy is beginning to go, and often give in after 100 rounds or so and do a light cleaning with a good carbon solvent. But on 3, I have not done any deep cleaning/copper removal for 250-300 rounds. I had one at the range this Sat. With it's favored load it would not shoot better than 4" at 200, when it was always 2 - 2 1/2" rifle at 200. So it will get a full cleaning before this weekend and back to the range it will go. I may just clean all 3 and start over, I don't know. This is the stuff that can drive a guy crazy...

I did have Barnes bullet accuracy issues pre grooved bullets. Since the grooves, they have been as dependably accurate a hunting bullet as any other for me. So if you duplicate the cleaning & accuracy issues, you may just have a gun that really likes to be dirty with barnes bullets. Were I you, I'd shoot it enough, clean and dirty, to make sure you have ID'd the issue. If that pattern is repeatable, alls well, if not, I might look for other gremlins. But even if the pattern repeats, it may make sense to lengthen the cleaning bullet count so long as accuracy holds.
 

Hilltop

Veteran member
Feb 25, 2014
3,842
2,226
Eastern Nebraska
24" is a drastic amount at 200 yards... I would be investigating deeper.

Another thing to consider is cold barrel vs hot barrel. When sighting in I like to give the barrel a couple minutes between each shot. I have never had more than a few inches difference between the two but it could be another issue compounding the clean vs primed barrel.

Sounds silly, but were you using the same ammo? From the same lot? Just grabbing at straws here but I can't imagine being that far off just from a clean barrel.
 

Colorado Cowboy

Super Moderator
Jun 8, 2011
8,306
4,682
83
Dolores, Colorado
I shoot everything (rifles & pistols) after I've cleaned them. I do notice a difference of poi after cleaning, but nothing close to 24". The one I do notice the biggest difference in is my T/C Pro Hunter .50 cal with black powder. It will change 5 to 6 inches when clean. Shoot it a couple of times and the poi is back where it was. I agree with Tim, I don't scrub out all the copper until accuracy starts to go, then it's time. I do notice a difference in my .17 HRM and my .220 AI Swift. They both need spotless barrels and need cleaning much sooner than my hunting rifles. My bulls eye target .38 S & W Masterpiece does not need barrel cleaning hardly at all. I shoot it all season (20 weeks) and only wipe it down. I shoot moly lubed lead bullets that don't lead up the barrel at all.

Every rifle is a little different. You'll need to find what yours like and stick to a cleaning routine.
 

HiMtnHnter

Active Member
Sep 28, 2012
445
4
Wyoming
Do what the rifle likes. Only way to know for sure is to isolate variables. I have a rifle that shoots great clean, not dirty. I have another that shoots great fouled. If it's a hunting rifle you really want to focus on the cold bore point of impact. Most all sporters will only shoot about 5 shots before accuracy falls off.
 

Umpqua Hunter

Veteran member
May 26, 2011
3,576
88
60
North Umpqua, Oregon
I'd like some opinions on an issue I'm having. I'm shooting a Thompson Encore 270 with 130 gr. Barnes. with a Burris Signature scope. The gun was zeroed at 200 yards a month ago. I then took it home, cleaned it, and ran a wet patch of Hoppes down the barrel and put it away. Last weekend I took it out, back at 200 yards, and the first two shots were 2 inches apart, but 24" high. No joke. Without touching the scope, I took two more shots, again 2 inches apart, but about 10" high. I then took four more shots without touching the scope,and they were all right where they need to be. I've never noticed such a difference when shooting a cleaned barrel, but it appears that it took those first 4 shots to "foul" the barrel, and then it was fine. I have not cleaned it since, and will shoot it "dirty" again this weekend to find out for sure.
What is really weird is that the "two shot" groups are close....2 at 24" then 2 at 10". I would have expected it to settle down after each shot if it was fouling the barrel, not "group" like it did.

I've had fits over the years with scopes and mounts and for that reason there are some I will never use again.

Next time you shoot pay particular attention to the cold bore accuracy, first couple of shots. You will be hunting with a cold bore.
 

Mr Drysdale

Active Member
Mar 24, 2013
437
332
I have owned some rifles that shot nearly the same poi squeaky clean or fouled. Had one that wouldn't print on a 8.5 x 11 target at 100 yards the first shot after cleaning. But only that first shot then back to original poi. Good Luck with figuring it out.
 

Roboz

Active Member
Mar 10, 2011
196
0
That's quite a bit! My 257 Weatherby hates a clean barrel, if i thoroughly clean the barrel it will be off 8 - 6 inches until i get the barrel fouled. I normally get it dialed in for the season and wont clean it until all of my seasons are done. once it's fouled it will shoot moa all day long.
 

Cobbhunts

Veteran member
Jan 22, 2014
1,060
1
Kentucky
One thing about an Encore that is extremely important from an accuracy standpoint. Always make sure the butt stock screw is nice and snug. That caused me fits one year until I finally figured it out. If it is loose even a little bit it will change your POI dramatically. The other posts have touched on anything else I would have added. Also...if you haven't checked out Mike Bellm's offerings for upgraded Encore parts, you should. You can really reach the fuller potential of an Encore's accuracy using his kits.
 

Roboz

Active Member
Mar 10, 2011
196
0
Cobbhunts is on to something with the encore, i had a 300 win mag encore that i had to install the oversized hinge pin from Bellm's before i could get a consistent group. It was a new rifle and had problems with it until i installed the pin.
 

Cobbhunts

Veteran member
Jan 22, 2014
1,060
1
Kentucky
Yes sir. If there are any "loose" connections there your accuracy will go to crap. I use the oversized pin as well. Along with his trigger kit and upgraded hammer and lock springs. Makes it good and tight from the frame up.

Sent from my SM-N910V using Tapatalk
 

LaHunter

Active Member
Aug 24, 2012
322
0
N.E. LA
you mentioned that you ran a wet patch through the bore and then put the rifle up. You never mentioned that you ran several dry patches down the bore to get the liquid out before shooting. That could have been the issue. Make sure to get the oil/solvent out before shooting.