I got a TF25 in .22. It shot 535fps with 14gr with a lot of twang, when I got it. I cleaned it up and polished and washered the spring. Shot harder,but not so accurate. The lock up design is the problem. I had to file down the breech and shim around the hinge pin. This got rid of the side to side, but the lock up was still bad and the hinge pin kept loosening up. I made new nylon washers for the hinge pin. This hinges on the right side only so the spacing has to be right to line up the port and barrel. The lock up chisels are not long enough for a tight lockup after they are fitted to the barrel, so I made a new one for the springed end and reworked the stationary end. I will need to remake these out of drill rod. I can foresee wear. Then the barrel kept producing rust. JB paste and cleaning then firelapping was the fix. The barrel still has a rough spot that can't be fixed. A heavy brass muzzle weight helped with the balance, but the trigger had to be replaced with a GRT. Then my son, RCnMO, made me a derlin guide. I put in a new spring, spun a button and installed an Apex seal. Used heavy tar on the spring and moly on the outer edge of the seal. Also RWS chamber lube to seal the chamber. This slows the action until dry, so be careful how much you use. I soaked the trigger assembly with slick 50 and let air dry. Now it shoots 732,735,732,735,733 with 14.0 gr match pellets. Same hole accuracy at 15 yds. NO kick no twang, but very hold sensitive. I'll try to post pics

I hope these come through.

That's pretty hot for a $75 rifle. Can't wait to put a few through it after Thanksgiving. If it's too cold out, we can shoot in the garage.