View Full Version : JB Bore Paste?

January 9, 2011, 11:57 AM
For you guys that use JB Bore Paste. I had a friend who gave me a M-70 300Win Mag but looks like the barrel was not taken care of took me about 3 hrs. to get clean and all of the fouling out. The barrel still looks rough to me and was wondering if JB would help? I read a Thread from Gale McMillan about to never use this in any barrel and if you did on one of his barrels it would void warranty. Just thought I would ask does it do good or does it harm? If you do use it how long should you brush? (Pros and Cons)

Thanks John

January 9, 2011, 12:03 PM

For you guys that use JB Bore Paste.

John, I use JB Bore Bright - Is this what you are refering too?

Jim Watson
January 9, 2011, 12:09 PM
In the first place, if it isn't a McMillan barrel then he isn't going to guarantee it anyhow. Or wouldn't if he were still alive.

In the second place, and more importantly, the barrel sounds somewhere between neglected and ruined, so what have you got to lose? I'd roll a patch around a worn brush, coat with JB and scrub the dickens out of it.

January 9, 2011, 12:33 PM
What are you using to clean it with now? Are you just using Hoppe's #9 and patches? Maybe a little copper solvent and a brush?

January 9, 2011, 12:45 PM
I was a little skeered to use JB so I started at one half what the instructions say because I was using it on a good barrel. Tested it, saw improvment, stopped.

January 9, 2011, 01:22 PM
I've used JB bore paste in several rifles,ans pistols ,with no ill effects.

January 9, 2011, 01:30 PM
jglsprings, Have used Shooter Choice Copper Cleaner, Butch's Bore Shine and Wipe Out, It is looking alot better went and shot it yesterday barrel fouled in about 7-8 shots with 180 gr. Sierra's and IMR 4831 just thought that a little JB would help the fouling. I did get a couple 1.5 inch groups @ 100 yards. I used JB along time ago but can't remember if it helped on the rifle at that time.


January 9, 2011, 01:35 PM
I've used it. In fact I used JB just the other day on a Winchester 1894 to brighten the bore up a bit. JB won't make an old, pitted barrel like new, but it can get stubborn fouling out of an otherwise neglected barrel. Used sparingly, it is great. Used aggressively, it is close to abuse. But it is just a cleaning aid, not magic, and not the devil incarnate.

January 9, 2011, 01:44 PM
Barrel is not pitted but it was neglected and thought that the JB might help smooth and keep from fouling as fast.

January 9, 2011, 01:51 PM
I think you are on the right path here. If the barrel is a little rough it should help. I've got a 7mm mag that takes additional cleaning to get the bore "right". I'd try a light swipe or two with the JB's and see if it doens't ease up as you shoot it more.

Moderation in all things! LOL!

January 9, 2011, 02:11 PM
Thanks jglsprings, I think I will give it a shot.

January 9, 2011, 04:04 PM

When I have a really badly fouled barrel of unknown history, I just put a chamber plug in and use a plastic oil additive syringe to fill the whole barrel with cleaner. After checking for leaks, how long I let it sit depends on how aggressive the cleaner is. Shooter's Choice is not very aggressive, so I'd probably leave it overnight. That works well with Butches Bore Shine, too. The maker told me he'd once left a piece of barrel steel soaking in it for six months and microscope examination showed no sign of etching in all that time. So it's good for a soak treatment, too. In the morning pour the stuff out into a jar to see whether it turned more blue or not? The soak will also help soften old carbon for patching out.

If your cleaned barrel (absolutely no more aquamarine color on the patches) fouls to the point accuracy actually decreases in fewer than 10 shots, you may have to do something even more extreme than JB, such as hand lapping or firelapping. Slugging the bore with a pure lead slug will reveal if it also has a constriction in that ares, which would be another vote for lapping. But try the mildest thing first, which is the JB.

Also, fouling tends to be greatest where the pressure is greatest because that's where pressure upsets the bullet hardest against the bore, creating the greatest friction. That's usually in the first couple or three inches after the throat. Unless your fouling pattern is different from that, I would concentrate the effort there. Use the patch method Jim Watson recommended but go back and forth a couple of times in those first few inches for each full pass down the bore you make.

January 9, 2011, 04:41 PM
Thanks Unclenick, You are correct the worst fouling is about two inches after the throat it also looks to be the roughest but after the first couple of inches the barrel looks pretty good. I will try leaving the Shooter's Choice in the barrel overnight but one question, this is the Shooter's Choice copper remover not the standard Shooter's Choice that states for powder and copper fouling. It smells almost as strong as Sweets.

Thanks John

January 9, 2011, 05:55 PM
I was thinking of the original, but either should be OK. If in doubt, give them a call and make sure it's OK to do. You could also just do it for one hour and see if there is any more blue or not. If not, you got it and there's no point in doing any more. If it has become more blue, put it back and add some more time and see if it gets darker.

Remember, "you control the horizontal, you control the vertical. . ."

Ideal Tool
January 10, 2011, 05:33 PM
Hello, txJohn. I have been using the original JB bore paste for years..just be sure to use a good rod-guide & quality (coated) rod..I like Dewey and Bore Stix. Don't be afraid of JB...At one of the shot shows JB booth had a ruger handgun set up with an electric motor driven cleaning rod with JB on patch. Ran entire show..at end, they measured bore and found no wear...but it sure was polished!

January 10, 2011, 05:57 PM
Thanks Ideal Tool, I will try it as soon as I can order.

Thanks John

January 10, 2011, 10:36 PM
Ideal Tool,

That's a good demo. Most people don't realize the JB breaks down finer and finer as it goes along. Nor that just polishing removes really small amounts of metal. It takes an awful lot to remove a ten thousandth you can see on a standard micrometer, and that never happens within the life of most barrels.

January 11, 2011, 02:06 PM
Unclenick, I use your barrel plug and fill with solvent method on my hunting rifles after every hunting season. I plug the breech end with a rubber stopper and fill the bore to the top with Ed's Red and let it sit for 24-48 hrs. Then I dump it out and clean with bore brushes and patches as normal. Really loosens everything up and makes it easy to get all the fouling out. I would do this along with the JB.

January 12, 2011, 05:00 PM
Thanks guys for all the info I bought some JB and will let you know how it goes.

Thanks John