You need to apply a quality breech plug grease to all the threads of the breech plug then screw it back into the rifle BUT DO NOT TIGHTEN IT DOWN HARD... FINGER TIGHT IS PLENTY. The reason for this is as you shoot the gun the plug itself with tighten. In fact many times after 10 shots take your breech plug wrench and just be sure the breech plug is still free and able to move back and fourth. It will save you a lot of headaches down the road if you wait too long after shooting. In fact if your range is any distance away from where you clean your rifle, remove the breech plug from the rifle (I keep a zip lock bag in the gear bag for just that purpose).

The best breech plug grease I have found out there is CVA Slick Breech Plug and Nipple grease. It has worked better then all the others I have tried, and I have tried a lot of them.

As for your load, only shoot 2 pellets with the powerbelts. They do not like a lot of push. Also before you shoot remove the plastic wad on the bad and take a dab of your grease plug grease (just a very small amount) and paint the lead spike. Then put the plastic wad back on. This will help the projectile shed the wad faster out of the barrel and give you better accuracy.

Good luck with your rifle