I tried BM3 and it was, at least, 200fps faster than T7. I had some accuracy problems and some large diffrences in velocity, from shot to shot. It is very clean and I am going to experiment with it some more(different grs. of powder and different bullets). You only get a little white residue when you patch between shots. It was quite warm(nearly 80 deg.) when I tried it. I am going to try again in cool weather.