Shim Nitro Piston

[michael word]

I am thinking about trying to shim the gas ram on my titan and would like to know if there is a certain distance it can be compressed to before you damage it and if anyone who has tied this before has any data on the performance gain.

[uncle paulie]

It's not something I would do as I think it could do more to harm the seal than add power.  At the point the piston gets to the end of the compression chamber, the pellet is already on it's way and there is an amount of back pressure which helps to slow the forward stroke and ease the impact of the seal against the end of the tube. Maybe some of the pro-tuners would have a different take on it.

pv

[ezman604]

I'm by no means a pro tuner but I'll throw one more safety consideration at you. By adding a preload washer, you MAY compromise the ability of the piston to travel all the way back to get a positive lockup when cocking. That is something to be VERY careful of. You can cause damage to the gun and yourself if you have a premature release of the piston/RAM. And in my mind (which is sometimes warped ) I can see adding a washer might limit the travel of the RAM and actually cause a drop in performance.
Happy Shooting!!!!
Dave
 

[airiscool]

If it's like the air venturi ram I put in my Whisper it may be at, or very close to maximum ram piston travel now. If you put too much shim in, the ram piston will bottom out inside the ram housing before the gun is cocked. At that point the cocking linkage is at maximum leverage and you can apply enough force that you could easily bend the ram shaft.

I tried what your thinking about by adding a very thin shim washer behind the rear end of the ram in my Whisper. When the ram bottomed it started to bend the ram shaft. Luckily I felt the increased resistance before it bent so bad that I wouldn't have been able to straighten it.

Paul