After polishing my barrel with JB paste accuracy is gone? Crown is not damaged but something went wrong, pellets look like bird shot on target.
Any help would be greatly appreciated.
Any help would be greatly appreciated.
so you shot from a tin and it grouped good , then you wanted it better so you polished it now it wont group with same ammo ? if so , the crown must have a nick or blemish , paste wont enlarge barrel to lose accuracy ,, did you do it on a lathe? is the barrel tight and installed properly > what kind of gun is it ?
This is why I get a significant amount of pucker factor at the mere thought of polishing or recrowning a barrel, especially on a gun that already shoots well enough and doesn't really "need" the modification. Not saying that was your situation, though. Hope it works out well for you.
My be try to clean the barrel. If it still has bore paste in it could be the problem. Also sometimes they need a little lead in them to shot good. May take 100-200 pellets
Maybe try larger diameter pellets. You don't give a guy much to go on . Different brands and sizes.
For most things I'm very reticent to fix what ain't broken but I've gotten to where I end up working on every new barrel I touch. Granted I don't deal with a lot of premium stuff but I'll go after a Lothar Walther, for example. Doubt I'd touch one on a Daystate, for example, unless something was clearly amiss.
That includes polishing the bore but I always work from the breech end and apply progressively fewer strokes out toward the muzzle. I've had some stinkers that never would shoot well and occasionally one that doesn't improve but have yet to have one shoot worse for having tried.
Hopefully a good cleaning and reseasoning clears it up!
so you shot from a tin and it grouped good , then you wanted it better so you polished it now it wont group with same ammo ? if so , the crown must have a nick or blemish , paste wont enlarge barrel to lose accuracy ,, did you do it on a lathe? is the barrel tight and installed properly > what kind of gun is it ?
I assume the JB treatment was done with a rod. If so, the "rodder" must exercise extreme care to not let the rod rub against the crown and/or the lands of the rifling at the breech end of the barrel. That JB stuff is a quite fine abrasive, but it can help damage a barrel if the rod rubs against those key contact points. This is especially true if the rod is a jointed one made of brass or aluminum. The joints, along with the soft metal, collect the abrasive so that it becomes an instrument of destruction. Bottom line: Don't let a jointed rod in the same building with a prized gun barrel.
Is your gun shrouded? Did you remove the barrel from the gun to polish it? You might have an alignment issue causing clipping.
Perazzisc3 - What gun is it??? People can probably help you more if you give them as much info as possible.
Also, if there is a breech O-ring, and you didn't remove it before polishing, have you inspected it after polishing?