I'm wanting to modify a Crossman Challenger to shoot Hunter Class Field Target. I had it shooting 11.5 FPE and was averaging in the 40's on a 60 shot course set up around a 38 troyer. I think I need a little flatter trajectory to be more competitive and improve my score. I've already got it to 17FPE using 8.44grn pellets with a 2300 psi fill by doing basic T/P and hammer spring mods. This is only giving me 12 good shots which is fine, I carry a guppy tank through the course at all matches and top off after every 12th shot. The problem is there isn't a bell curve to the shot string, it's a constant drop after the second shot. The string starts at 958fps and at 12th it's at 931fps at 1700fps and a SD of 8.6. The current set up is t/p opened up guessing at 0.090, hammer spring is 0.047 wire same length as factory which is 0.035 wire. I'd really appreciate it if someone already has theirs tuned to a similar tune to share what they did to theirs. I think the ultimate tune would be at 19-19.5fpe with a 10.3 grn. pellet.
My second concern is the bolt. By increasing chamber pressure(for lack of a better word) to achieve 19-19.5fpe, am I going to have a problem with the bolt flying open during the shot?
Thank You in advance for your time and or Advice......
My second concern is the bolt. By increasing chamber pressure(for lack of a better word) to achieve 19-19.5fpe, am I going to have a problem with the bolt flying open during the shot?
Thank You in advance for your time and or Advice......