I am not sure what you mean by "cleaned". At the range, I run a patch soaked in T/C black powder solvent down the barrel followed by 2 dry patches (both sides) between each shot. If you are doing that, you shouldn't have to do furthur cleaning to get better groupings.

One possibility is that your gun doesn't particularly like 100 grains of pyrodex. For those guns that do, then pellets are great. However, you might really tighten up those groups by using 95 or 105, etc. I have always used loose powder and recently switched to triple 7. It took me a while to find and accurate amout (turned out to be 90 grains), but it is so much easier to clean! And the 777 is about 15% hotter. I chronographed my load and it came in the same as a 105 grain pyrodex load.

HOwever, if you use the 777 pellets, they are NOT hotter. They dilute them to have the same power as 100 grains of pyrodex.