File this in the FWIW column, which may not be much if you are not an ardent blackpowder shooter.

I decided to risk another PVC barreled gun one more time. After the last time I was pretty leery of shooting plastic shotcups again but I was also still surprised at how bad the plastic fouling was. So, this time, I loaded up the same load with one modification. I soaked the fiber wads with lube - mostly SPG and some other similar odds and ends of BPCR bullet lube that i had on hand. This made the wads stiffer so I had to shave them down a little to get the loads to fit together but otherwise, they were identical to the loads that had turned my shotgun into a plastic mine.

The end result is that there was still plastic fouling after one round of trap. However instead of taking 2 days and the better half of a can of Kroil to soak and brush with, I needed only two spray downs with Kroil and about an hour of soaking or less and the gun was clean again. So, the problem is MUCH better with the lubed fiber wads, but they are not altogether absent either.

From my perspective the targets were well broken most of the time, suggesting I had a good pattern. Better than when I have used only mylar or nothing at all for shotcups. So I think the effort is worth it. However, there is not much likelihood of shooting multiple trap rounds without some stiff brushing and wiping between rounds. More than I probably want to do. So I'll save the bp ammo for hunting in the field and my last round of trap for the night.

Anyway, there you have it. Lubed wads really made a difference. I presume that is because they sealed the bore much better, preventing blow-by that probably badly melted the cups in the previous outing. They also probably resulted in somewhat faster velocities though I have no data to prove that one way or the other.

Thanks for bearing with me. The conversation helped me isolate the wads and the lube issue.

Brent

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BrentD, (Professor - just for Stan)
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