HW45 Piston Damage

[cjtamu]

The wear to your piston is unusual as it is 90 deg to where you might expect it (more usually coming from cocking arm galling, or 180 deg to the cocking arm caused by the force applied from the cocking slot side...

Tin bum kits damp these guns but destroy what they were designed for, namely 6ftlb hand canons.
They will do much better with the weight left in the piston, preventing piston rebound but learning to shoot the gun and enjoying 600 Fps instead of 450 fps..
You can get 600 fps and a reasonable damped cycle by selecting pop gun phase pellets but with big dia skirts which seal the gun up better, using all the available compression volume.
Hobby and Superdomes do a good job of this, as do the larger skirt AA FT.
Then go learn to shoot it...
Piston head is teflon....

There’s the man I was looking for. Your write ups were a huge help getting this working properly again, many thanks. Mine’s a .22 so if I get 600 FPS I’m going to notice ha ha. I’ll get a better pic of piston next time I disassemble, but I honestly don’t think it’s wear. Nothing in compression tube is rough, no scarring, there were no metal bits or shavings, nothing to indicate it happened while in the gun. It was beautiful inside except for the piston. These are gouges, not surface scratches. Really starting to think it came from the factory that way. Shooting beautifully with RWS Hobbies and almost as well with the Excites. Figured out already it liked the bigger skirts thanks for confirming. Really is a joy to shoot. Now just have to get Ron on board ha ha.

 

[cjtamu]

Put about 120 pellets through today. Nothing moved. Recoil stop screws loosened a little. Might need a dab of Loctite there, we’ll see. RD zeroed quickly and held zero the whole time. Happy camper so far.