In m y Pro Hunter I had a crud ring begin after the 1 st shot of T7. cayugad, good test i will be interested to see what your findings are. I don't think T7 was that bad a shooting powder, i just found it a real pain to constantly swab between shots. After shoot cleaning was dirty as well but no something that bothered me. I do it no ,matter what I shoot, but the range time it was horrible for m,e.