68 carbine problem

Please help.  I have a .68 Carbine.  I dont remember what year but it is in mint condition and I only played with it about 6 times over the years.  The problem is that when I get the marker chrono-ed the FPS stays around 300.  The velocity adjustment screw is all the way in and it cannot be adjusted down anymore.  This is bad because the field I have played on has a speed limit of 290 FPS.  Any suggestions?  This marker has always had this problem.  I never noticed it before because I never had the speed limit less than 300 until recent.  This marker is incredibly reliable but has this one problem.  I also have installed on it a smart parts extened rifled barrel.

Any help is greatly appreciated.

Cutting the spring should definitely do it. I had the same problem on my 68 carbine and I also had to cut the spring to get the velocity down. Mine was worse though, I think it was at like 340 or something absurd. I cut probably about 2 coils off and that dropped it down to a safe level. If you cut too much, go to www.tippmannparts.com and you can grab a new one without buying a whole kit.

Nope, just standard bent ends. Precision isnt too critical. Good luck,  68 Carbs

Thanks again for all the help.  I have also replaced the plastic feed neck.  Thats the only complaint I have about this marker.  I have my plastic neck supported with 2 wire ties to prevent it from coming off during play.  So far so good.  Great marker but bad neck design.

I played last weekend and so many people were asking me where I got a 68 carbine in such perfect condition.  Some were even considering making an offer for it.

68 Carbs are classics. Dont sell it. Ever. Unless its to me, of course