JB Bore Paste

[Carl323]

Is there any reason to use a bit of JB bore paste in your muzzleloading barrel? I read different things about it, even shooting a couple of patches lubed with it with your round ball every once in a while. If recommended for any use, are there different types that may be better? Thanks.

 

[mhb]

None that I can think of...
JB is a very mild abrasive intended only for the purpose of removing fouling from modern arms, including copper/gilding metal fouling, which it does very well.
It is not intended to polish the bore, and is not hard enough to do so properly.
I do not recommend shooting it on a patch or leaving any amount of it in the bore when shooting - it can act differently under those conditions. In fact, a friend 'JB'd' the throat right out of his .223 match rifle by failing to fully remove the stuff after cleaning the barrel - enough remained in the mouth of the chamber to wash the throat right out of there - I know this because I made the barrel and borescoped it when he noticed the reduced accuracy.
mhb - Mike

 

[crockett]

The steel on a modern firearm might be harder and stand up better to JB. I have used it on modern revolvers. I shoot PRB- no lead problems.

 

[Irish lad]

Being a lazy, impatient sort, I have used it on new ML barrels that were cutting patches.
It has helped.
I agree with Mike that it must be removed completely.
Cheers,
Irish

 

[Patocazador]

Being a lazy, impatient sort, I have used it on new ML barrels that were cutting patches.
It has helped.
I agree with Mike that it must be removed completely.
Cheers,
Irish

Agreed, it is a good way to "hone" a new unfired barrel. Just run a tight brush/patch up and down the barrel about 50-100 times with JB Bore Paste or Remington 40X and it smooths it right up instead of shooting that many shots to get it right.

 

[Brokennock]

I've used colgate as a "poor man's lapping compound" before, how does JB paste compare in abrasiveness?

 

[George T.]

It wont hurt a barrel but I'm not sure it does much good. I have used it to remove copper in modern firearms. There are better things for that also.

Geo. T.

 

[just4fun63]

I've used it to help revive a old barrel. Helped to smooth out the rough spots.

 

[Spikebuck]

I have used it from time to time in muzzleloaders that I shoot conicals or lead shot out of. I don't use it every time I clean, but once in a while. I think it does a good job of getting out what "normal" cleaning won't when shooting lead without patching.

 

[AZbpBurner]

I've used colgate as a "poor man's lapping compound" before, how does JB paste compare in abrasiveness?

The idea behind JB Bore Paste is a material that will scrub out lead and copper fouling without wearing the bore. It's not an abrasive suitable for wearing in a barrel. If you want to lap a barrel and don't have patience to break it in by actually firing a hundred rounds or more, then go get some actual lapping compound. JB wasn't made to abrade or wear down steel.

 

[hanshi]

I'll bet your rifle's bore smells good! :rotf:

Used properly, JB paste is excellent for cleaning an abused or super dirty bore of a muzzleloader.

 

[Brokennock]

Haven't used it in a bore. But I have used it to smooth the action of other working parts on more modern guns.

 

[Rokon]

I use it with success to smooth out a bore that may have spots in it that seem to attract fouling also for giving a brand new barrel a very slight polish. Have also used SIMICHROME POLISH with success to polish a new barrel.

Remember--all modern custom barrel makers lead lap their barrels with 150-220 grit. Why? So they can achieve their objective with the least number of passes through the barrel.

You are NOT going to harm a ML barrel with JB.

 

[FishDFly]

Is there any reason to use a bit of JB bore paste in your muzzleloading barrel? I read different things about it, even shooting a couple of patches lubed with it with your round ball every once in a while. If recommended for any use, are there different types that may be better? Thanks.

Get 100 balls, 100 or so patches of different thicknesses, a bunch of cleaning patches, caps or flints, some powder and learn to shoot the gun and see what it likes for powder charge, patch thickness and ball diameter.

That is the answer.

 

[Billnpatti]

If the lands in the bore of a new rifle are sharp enough to be cutting your patches, they need to be smoothed out. A barrel can be broken in simply by shooting a couple hundred rounds through it. If you want to speed up the process, the two simplest ways are to use some 000 or 0000 steel wool wrapped around an undersized bore brush. Do not use a bore brush that is the size of your bore. They will often become stuck in the bore. Wrap enough steel wool around your brush to give it a snug fit in the bore. Apply some oil to it and start polishing your bore by using good long full length strokes. Using full length strokes is important because you want your bore to be the same the whole length. Change your steel wool after every 25 stokes to keep it polishing effectively. It will take about 100 to 200 strokes to lap your barrel and remove the sharp edges from your lands.

Another method is to use an undersized jag with green 3M scouring pads. Just cut the pads into strips that will fit on your jag and give a snug fit. Use oil and do the same as with steel wool. Either way will remove the sharp edges from the lands and polish your bore. A polished bore will prove to be less of a fouling problem than one that still has the tool marks left in it to catch fouling.

 

[nkbj]

JB's claim to fame is being a non-imbedding abrasive compound. In other words it doesn't embed into the metal like other modern abrasives and make the barrel itself become an abrasive surface. That's why it's good for guns.

JB will remove metal. I used it on a lead lap to slick up the first muzzleloader I ever had in the middle 70's.

If your barrel is rough a JB lap can make it better. Nowadays I use the clay that the crawdads bring up.