Some interesting things I've found on my Hammer 7: the threads for the bottom line are standard, the tip threads on the stock barrel accept CP tactical barrel tips, mine also burps when pumped hard, and the cup seal is completely threaded on.
One side of the bolt is flat, and I'm not sure if I like this feature or not but the diagram in the manual doesn't show it or tell you which way the flat is supposed to face. Spyder freak backs don't fit the pump handle without modding. The 45 grip and rails are all to spec, and the trigger is nice. With crappy paint I still had consistent chrono readings and no trouble adjusting to velocity.
The ball latch on the mag is only good for 8 rounds, when the 9th round is loaded the feed spring over powers the latch and your entire mag launches out the top. I have 0 issues loading the mags or loading them into the gun.
Just my findings so far, feel free to ask questions