I recently did a little testing on plastic removal. For the background, I was sending a 300 gr Hornady 458 bullet down range at 2300 plus fps, over a low buck chronograph. I was using MMP sabots. I was not using BP, I was using smokeless. I purchased some plasitic removing solvent from Brownell,s. I also have some JB bore paste. These were both compared to Hoppe's No 9 and a bronze brush.
There was no actual chemical testing done, just checking out the color of the patches and number of passes etc. In my ML, I found JB bore paste was slightly faster than Hoppes no 9. After either Hoppes or JB I could find no color, other than the nice pink of the plastic remover, when treated with the Plastic remover. Another fellow had commented that no plastic fouling will hold up to a bronze brush. I am in agreement with his statements.
My ML needs a couple of fouling shots after a deep cleaning.
Use enough gun.