Copper fouling after Losso use

TAZMAN

Well-Known Member
Joined
Oct 23, 2003
Messages
833
Location
Indiana
So I have a 260 that I use to shoot matches and it has done very well. Usually shoots in the .3 range with H4350/142smk combo. Last week the groups opened up so I looked at it with a bore scope and noticed the fire-cracking has some pretty good carbon I couldn't get out. I used a small bit of Losso on a nylon bore tech brush after doing my normal bore tech patch and brush work then I flushed out the Losso and it looked clean with no 'grit" feeling from the dry patch. Looked good and it went back to shooting .3 inch groups but after 35 rounds the group opened way up.

I looked at it with he bore scope again and it has copper streaks everywhere in the barrel and it has never done that before. I used very little Losso and the barrel has about 2900 rounds through it so I suppose it could be getting close to the end of it's career but the copper fouling seems odd. I did not use enough Losso and strokes to hurt anything I didn't think but maybe I am missing a step to re-polish the bore. I tried a little JB bore past on a patch to polish it a little more then shot it yesterday and the same thing....35-40 round in 5 shot groups with 40 minutes between strings and it copper fouled then opened up.

Am I missing a step or is the barrel done?
 
If you have stripped it/ cleaned it down to bare metal (with fire cracking)--- you might need to "season" it again-- shoot 1 or 2- clean- repeat--- if you can get a little carbon built back up it will help resist the copper fouling.
I know some guys that actually will "dust" the clean bare steel barrel with graphite powder before shooting to keep the copper fouling to a minimum. I've never tried it though

Each bore is slightly different so you might have to try a few things-2900 rounds is getting up there too but if it's still printing .3 groups than it could have more life in it

Probably going to be a wide range of opinions here though. Good luck and let us know what you figure out
 
Thank you for the reply, I only used the Losso to get the carbon out of the throat area and it has a little fire cracking about 2 inch down the bore. As I am typing this I am cleaning the barrel again, no carbon fouling to speak of but streaks of copper even toward the engine of the barrel.
 
About 2900 rounds.
I have never had a barrel make it that far, not even close. The only barrel that might make it is a .308Win which has at about 2,000 rnds and still looks pretty good.

It would be great if you could get the kind of accuracy back that you're looking for but, IMO, that barrel is probably long overdue for replacement.

BTW - I have lightly used ISSO to get stubborn fouling out of a few barrels and have not experienced the problem that you stated. I didn't use a bore brush but I doubt that makes any difference.
 
If you have stripped it/ cleaned it down to bare metal (with fire cracking)--- you might need to "season" it again-- shoot 1 or 2- clean- repeat--- if you can get a little carbon built back up it will help resist the copper fouling.
I know some guys that actually will "dust" the clean bare steel barrel with graphite powder before shooting to keep the copper fouling to a minimum. I've never tried it though

Each bore is slightly different so you might have to try a few things-2900 rounds is getting up there too but if it's still printing .3 groups than it could have more life in it

Probably going to be a wide range of opinions here though. Good luck and let us know what you figure out
I tried rolling a loaded bullet in graphite and also molybdenum on a paper towel and shooting single shot. Goal was combination of velocity, accuracy and reduce fouling. I could not see enough improvement in any category to be worthwhile so gave up.
 
I figured it was at the end of it's accuracy node. It just confused me a little that it will shoot 5-7 half moa 5 shot groups then opens up to 1.5 inches. I will wait until after the holidays to ship it out. They lose enough stuff during slow times let alone with this time of year!!lol
 
So I have a 260 that I use to shoot matches and it has done very well. Usually shoots in the .3 range with H4350/142smk combo. Last week the groups opened up so I looked at it with a bore scope and noticed the fire-cracking has some pretty good carbon I couldn't get out. I used a small bit of Losso on a nylon bore tech brush after doing my normal bore tech patch and brush work then I flushed out the Losso and it looked clean with no 'grit" feeling from the dry patch. Looked good and it went back to shooting .3 inch groups but after 35 rounds the group opened way up.

I looked at it with he bore scope again and it has copper streaks everywhere in the barrel and it has never done that before. I used very little Losso and the barrel has about 2900 rounds through it so I suppose it could be getting close to the end of it's career but the copper fouling seems odd. I did not use enough Losso and strokes to hurt anything I didn't think but maybe I am missing a step to re-polish the bore. I tried a little JB bore past on a patch to polish it a little more then shot it yesterday and the same thing....35-40 round in 5 shot groups with 40 minutes between strings and it copper fouled then opened up.

Am I missing a step or is the barrel done?
If you polish a turd, all you have is a polished turd. Time for a new one.
 
There are a couple other things you could try since at this point you don't have anything to lose! I think my first try would be the finer grits of a NECO firelap kit. There are 4 grits but I would be leery of using the coarse grit at all. Maybe the second grit but more likely in a good shooting barrel I would try the last two first to see if it works. I have never had an accuracy change from using the NECO process but then I've never used it on any of my custom barrels, either! Just factory. It cuts way down on fouling, which seems to be the problem with this barrel.

Another possibility would be a stainless polish such as those used on aircraft. My #1 recommendation would be Metall (available from Aircraft Spruce & Speciality) or a product called Noxon 7 (you'll have to search for that one, I've had the same bottle for years!). Both of these are aluminum & stainless steel polishes and are even finer than JB (I think... none of them list the actual grit size but all are super fine). For that fact, you might even try the JB Bore polish, which is supposed to be a finish product for the JB Bore cleaner. Just some possibilities and again, I've never used any of them on a custom, hand lapped barrel so you're in uncharted territory as far as my experience goes!
Good luck!
Cheers,
crkckr
PS. I do love those Hart barrels!
 
Thank you for the information and as you suggested I used the fine JB paste last night and did 35 strokes from the action to the muzzle to see if I could smoot it a little and help it. I don't want to ship it out right now with the Christmas rush, for fear of it getting lost, so I am just playing with it to see what it does.

I have 4 other full custom 6.5 rifles that shoot one ragged hole but this rifle has been with me for a LONG time and although it may not be the latest and greatest, it has placed second twice at matches and usually is in the top 10 back when I shot more. We moved to the country last year and I have a place to shoot now so it's getting some field time again!

As stated, I am really impressed with the number of rounds I got out of this Hart barrel.
 
Tubbs used to make bullets with polishing compound on them would load and shoot it worked on my 264 win mag . It polished the bore back it helped for about 300 rounds for that barrel
 
Top