My first thread here, so I thought I'd share my project.
I wanted to try pump play but didn't have much money, so I got a good condition Trracer off Craigslist for $30. All it took was a 1/4" spacer on the main spring to bring the velocity up to 290. Problem is it shot horribly and could not stop roll outs. Not fun at all. So, being a tinkerer, I couldn't resist modding it. Using what I learned here, I started with polishing the internals, then 45 grip from an extra gun I had around, bottom line with an extra Cocker regulator and finally Cocker threads and bored out pump handle.
So far I've played with this set up once and was very pleased. I used a J&J edge elite barrel kit and Midnight Paintballs and it was accurate enough for me. I just got a Lurker barrel though and am really impressed with the improvement in velocity and accuracy. Five random shots were 285, 285, 287, 287, 285.