A bit of shiny lead found on a patch

[RScott]

Does finding a bit of lead particle on a patch indicate a need to polish a barrel?

This patch was pulled after 75 shots through a .177 stainless steel slow twist polygonal barrel shooting JSBs at about 830 fps. The pull used 2 dry patches and there was good resistance on the Patchworm line while pulling it through the barrel.

The patch is quite clean - I used hexagonal boron nitride on the barrel and pellets to avoid lead fouling. But I found a large speck and small spec of lead on the patch. The picture shows the large speck. I was very surprised to see the speck of lead and yet no darkening of the patch as is usually the case.

It got me wondering what would cause a speck of lead to get formed in a the barrel and then not come out during shooting but only with a patch pull through. The pellets had been washed. Does this suggest there is roughness or scratching in the barrel and polishing with JB bore paste or a more aggressive cleaning is needed?

 

[Richieg]

I'm thinking that a lead pellet going thru steel lands in a barrel may leave a few lead particles. When I clean my PCP barrels I sometimes have lead particles on the patch and sometimes not.
I'm sure there are some PCP experts on the forum that may chime in, I'm not.

 

[JaceSpace1369]

Does finding a bit of lead particle on a patch indicate a need to polish a barrel?

This patch was pulled after 75 shots through a .177 stainless steel slow twist polygonal barrel shooting JSBs at about 830 fps. The pull used 2 dry patches and there was good resistance on the Patchworm line while pulling it through the barrel.

The patch is quite clean - I used hexagonal boron nitride on the barrel and pellets to avoid lead fouling. But I found a large speck and small spec of lead on the patch. The picture shows the large speck. I was very surprised to see the speck of lead and yet no darkening of the patch as is usually the case.

It got me wondering what would cause a speck of lead to get formed in a the barrel and then not come out during shooting but only with a patch pull through. The pellets had been washed. Does this suggest there is roughness or scratching in the barrel and polishing with JB bore paste or a more aggressive cleaning is needed?



View attachment 363980

View attachment 363979

I have found that 177 barrels tend to foul up much faster than other calibers. I personally polish all 177 barrels I get for that reason. It has helped with keeping the accuracy for a much longer period of time and not having to clean the barrel anywhere near as often. It's also helped with pellet picky barrels.

 

[nervoustrig]

If I’m seeing it correctly, it is fairly 3-dimensional. When lead sloughs off in a bore, it is usually a flake...more 2-dimensional. Little shimmering flakes in the patches.

If the barrel is consistently accurate, you can reasonably disregard it for now. Maybe it was a loose piece of lead that broke away from a pellet left behind in the baffles or the breech O-ring groove.

Otherwise remove the barrel and inspect it carefully at each end for sharp edges. Especially at the barrel port, the transition into the rifling, and at the crown. And/or push a couple of different pellets through to feel for a place it catches hard.