I have the aftermarket breech plug from a source whose URL and name appear to be banned from this site, if you want I'll PM you the info. It allows use of 209 primers without the carriers and ALL of the gunk stays in front of the primer. Some other guys with this plug have experienced a little gunk ring around the firing pin port in the standing breech face, but I use Kleenbore ML primers & haven't experienced that yet. I use Birchwood-Casey choke tube lube on the plug threads but some guys use pink HD plumber's teflon tape with good results, seems that would keep threads cleaner than my approach. Combined effect is no blowback finds its way into any part of my rifle other than where I put the powder & bullet. As for what's already in your triggerworks, I recommend pulling off the barrel & stock & soaking the whole receiver in a good solvent (in an ultrasonic parts cleaner if you have access to one, I used dry cleaning solvent) followed by blowing it out with your air compressor. I have a very old H&R shotgun that had a hair trigger when I got it, but after doing that I can only assume I removed congealed gun oil that had gunked up a the hammer notch in the trigger or something like that. Can't say for sure but I recommend you try it before paying H&R, UPS, or your local gunsmith. I just know it's held together with a lot of pins I don't care to mess with so I didn't disassemble mine before giving a good cleaning a chance. Trigger went back to about 4 pounds, with a discernable break that felt right.