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Copper fouling questions

Cerwinski

Sergeant of the Hide
Full Member
Minuteman
Feb 16, 2019
161
67
Bought a Bergara HMR in 6.5 Creedmoor in early May. Broke it in according to the instructions. I have been pleased with it's accuracy (sub 1/2 MOA with handloads) but it seems to copper foul very easily. I have enclosed a pic of the muzzle area after 32 shots (started with a freshly-cleaned gun). Would this considered normal? My 700 in .243 does nothing like this.

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Sorry for the low quality pic but it shows the issue. Copper streaks on all the lands. The gun has exactly 250 rounds through it by now and I am anxiously waiting to see if it settles down. Yes I do notice a change in my groups after about twenty shots. Any advice appreciated. I want to feel good about this gun.
 
140 ELDM over 41.6 grains H4350. Average of 2690 with my Magnetospeed. I was so hoping it would have quit fouling so much by now. Getting tired of having to clean to bare metal after every range trip. I'm starting to think some sort of bore paste may be in order.
 
Probably because I can notice a difference in how it groups after twenty shots. Goes from shooting 1/2 MOA to 3/4-1 inch QUICK. I see nothing else to blame other than the fouling.
 
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Goes from shooting like this:

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To this:

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within five-ten shots. Driving me nuts.
 
My brother's Tikka is the same way. Shoots great on a clean barrel but very quickly fouls the factory tube. I think some factory barrels shoot well, but are rough enough to foul very quickly and be picky. My only solution so far has been to clean very frequently. I've been tempted to try some Tubb's final finish or something similar, but I have not yet so I can't comment on whether or not that would help you. Might be worth researching though.
 
So if you’re taking the clean rifle to the range and shooting 20 or so rounds thru it when it starts to open up, leave. Don’t clean the rifle. Come back with the gun as it was and see if it’s still shooting wonky. If it still shoots wonky right off the bat, then you know your gun likes to shoot clean. If it’s tight again, it might be eye fatigue or gun setup.
 
So if you’re taking the clean rifle to the range and shooting 20 or so rounds thru it when it starts to open up, leave. Don’t clean the rifle. Come back with the gun as it was and see if it’s still shooting wonky. If it still shoots wonky right off the bat, then you know your gun likes to shoot clean. If it’s tight again, it might be eye fatigue or gun setup.


After this last cleaning (barrel soaking right now) that's exactly what I'll do. My OCD can get the best of me if I let it.
 
Might be worth exploring Reloder 16, it has an anti copper additive added and like H4350, it is magical in the creedmoor.
 
Does R16 trade carbon issues for copper? I thought I had read that somewhere...
 
RL is definitely a solid powder, however it is slightly dirtier than H4350 in the carbon department as confirmed with my Lyman bore scope
 
Mine does that, 41.5 H4350 under a 147 ELD-M. However, mine keeps shooting 1/2 moa, at least to 150 rounds. I broke down and cleaned it after that.
 
Generically speaking, groups will open up once a barrel gets "dirty"



What constitutes "dirty" is different for every rifle.



I have also noticed that in overheated barrel can open my groups up or at least shift point of impact.
 
Interesting. I’m curious to see how this shakes out. I haven’t shot a factory barrel in a precision rifle in over 20 years.
I’m interested in knowing how this goes.
 
To answer one question, all were shot unsuppressed. This will be an ongoing experiment. From here out I will avoid cleaning until a definite repeatable degradation in accuracy occurs. To help eliminate shooter error (eye fatigue, etc) I will limit my range sessions to no more than thirty-five rounds each. Since I go at least once a week we'll know something soon. Thanks for all the advice! Will give updates as I go. Starting with a freshly cleaned to bare metal bore BTW.
 
I haven't shot without the can since I got it out of jail.

You're overthinking this. The can has zero impact on the fouling in a bolt gun.
OF COURSE a can increases bbl fouling. Even in a bolt gun. And that will at some point degrade accuracy. SMH.


For me, accuracy has fallen off a cliff TWICE right at 50 rounds suppressed.

Others may have an accuracy degrade at different round counts, but that's the way my gun works.

I have suppressors for almost all my modern firearms. In EVERY SINGLE ONE, bolt , semi or fa, the can accelerates bbl fowling.

Suppressors create back pressure past the end of the muzzle for every single firearm. That pushes more fouling back into the barrel.

They have not yet invented the firearm where this is not true.
 
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So if you’re taking the clean rifle to the range and shooting 20 or so rounds thru it when it starts to open up, leave. Don’t clean the rifle. Come back with the gun as it was and see if it’s still shooting wonky. If it still shoots wonky right off the bat, then you know your gun likes to shoot clean. If it’s tight again, it might be eye fatigue or gun setup.
This. But if it still shoots bad do 1 shot and clean until it stops leaving much copper after 1 shot. My 300 Norma did this and I had to do typical break in and then do 1 shot and clean about 7-8 times after that and then it settled down. If there are tooling marks grabbing copper the first shot will smooth them a little bit will but will cover them with copper. This won’t allow the next shot to smooth them anymore and will just grab more copper. Need to shoot 1 and clean down to steel until the one shot doesn’t leave much copper. IF you are positive it is the copper causing it. All barrels show copper at the muzzle after a few shots. The question is if it’s affecting accuracy.
 
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Don't be afraid of Sweet's 7.62 and/or JB Cleaning Compound (the original, not the Bore Bright). But yeah, a little copper streaking at the muzzle is common.
 
Get some CR-10 and get all of the copper out and do a break in on the barrel. I know it's very inconvenient and takes a while but it will help. As Precision Underground posted above, if not cleaned after each shot when breaking your barrel in, it will not change. The bullets have to smooth the machine marks out of the barrel and can't when they are riding on copper. It really depends on how rough the barrel is as to how many shots and how many times it has to be cleaned before it will quit fouling as bad.
 
41.7grn of H4350 is my load for 136 L. I just rolled over 1K round count on a Bartlein 5R 30” pipe and no significant copper at the crown like yours (yet). After ~100 rounds I do a nylon brush & nitro solvent type cleaning. After 500 rounds I do a good powder & copper removing cleaning using the Bore Tech eliminator stuff. After the big cleaning, it takes sometimes up to 8-10 foulers to group up again. I noticed that the 6.5-284 folks say about the same thing.

When my .308 Palma went out at 2750 (Varget power), it had copper galore. After using copper removing foam at the end of one season (never again) , it never really came back under MOA.

The IMR Enduron powers make a label claim that it reduces copper fouling. IMR 4166 or 4155 might be worth a try, 6mm folks seem to like IMR 4166 a lot.
 
interested in how it goes. the rex dude on YT talks about copper a bit, suggesting your groups might tighten up as the amount of copper reaches a certain point, and then opens up again after some time, requiring cleaning.

 
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Far as I can tell the barrel gods are saying… "everyone's barrel is different. Go figure out your own barrel. "
 
Just cleaned mine today after 40+ rounds (I can’t remember when I cleaned it last) and got zero copper fouling out of it. Got a bunch of carbon but no copper. I’m using Reloder 16 and shot Berger and Hornady bullets out of it. It’s a Bartlein 5R with about 200 rounds through it. My Shilens do almost as good but not quite. Did the full break in on all and I have been blessed.
@ garandman,
I did the seating depth test with the Bergers and at .120 out of the lands, put 3 in 1 hole.
 
Most if not all higher end barrels are lapped before shipping to a costumer. Factory barrels not so much. The whole barrel break in procedure is essentially lapping your barrel with projectiles; shoot a round, clean, repeat. A lot of people say it's a waste of time and it probably is for a barrel that's been lapped by a competent manufacturer, unless you have a factory barrel that needs to be lapped (see @Precision Underground post above). The coarseness and tooling marks in the barrel needs to be smoothed out without just covering it in copper. At least that's what I gather from reading random posts on the hide.
This is true but the part I missed was that even with a really high end barrel, chambering can leave tooling marks in the throat. So unless it is lapped *after* chambering you very well may need to break it in.
 
Don’t forget carbon rings that can build up no matter the age or smoothness of the bore. And can be a real challenge to remove. I use JB Bore Paste in the throat on mine every so often.
 
After this last cleaning (barrel soaking right now) that's exactly what I'll do. My OCD can get the best of me if I let it.


Thanks to those that said to give it a rest and go back another day. Turns out it was me after all. Guess I was getting a little tired and got sloppy with my technique. Went back Sunday without doing any sort of cleaning and it grouped like it should again. I can deal with a bit of copper fouling as long as it groups decently. I did, however, run a patch with Hoppes and a nylon brush to knock down the carbon a bit. I figure I should be able to go about 150 rounds or so before doing any real copper removal. BTW I have found the Gunslick foam to be very good. I had a can sitting on my shelf for years but for some reason I never used it.
 
Happens to all of us. We usually blame the equipment prior to blaming ourselves. Ask me how I know. ? Glad your all squared away. Within 10 shots of each other after spotting half the day for my buddy. Its rare for the rifle to go over 3/4”. Packed it up after the big group.
 

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