fx dream pup 25 with power plenum power question

[steppenwulf]

it might be a little early for this question, but here goes. i have one on the way. i'd like to shoot 33 gr. jsbs around 880-890. anyone out there have this gun tuned up? be interested in your tune-HS and reg. and accuracy. any help would be appreciated.

 

[wimpanzee]

My dreamline .25 with the human reg and the original Huma plen extension ( not the fx one or the xl huma one) spits the 34gr jsb at 860fps at 130bar on the regulator. If I shim the hammer spring another 1mm I can get 890fps, but the string starts to vary widely at that point, swinging by up to 60fps (yes, some 820 shots in there...) But at 1mm shim, I get 7fps spread and a SD of less than 2. Raising the regulator didn't do much for the fps.



I do have the fx plenum extension on the way too. Hoping to get a stable string at 900fps with it.

 

[JoeKool]

Got the FX Plenum (17cc) installed on my DreamPup .22, but I also have a custom 2 inch plenum spacer (30cc or so) stacked or combined with that. It equals about 35 to 45cc additional plenum volume. My barrel TP is enlarged / ported and my HS is modified to hit harder. I have up graded and installed a 290cc .25 caliber Dreamline air cylinder tube. With a 600mm slug liner, 125bar regulator setting, transfer port power wheel on .25/.30, the “MAX” hammer spring setting shoots JSB 18.13 grain at 1030fps, and the “MIN” hammer spring setting shoots 18.13’s at 850fps. I only need to adjust the hammer spring setting to shoot at virtually any speed between 850fps and 1030fps. For example (with JSB 18.13’s) HS setting “C” gives me 980fps, HS setting “4” gives me 960fps, and HS setting “3” gives me 920fps, etc.. etc. Getting 70 shots per fill when using 18.13’s with .25/.30 transfer port, “C” setting on the H. spring dial, and the AMP regulator @ 125 bar. It is accurate all day if my wind hold is right. Here are some rushed 5 shot groups at 25 and 75 yards. The small 2 inch targets are only sighters.

 

Like I mentioned, groups were rushed and there was gusty winds. 10-15 mph.

I can’t speak on the .25 caliber DreamPup because my gun is a .22. I think though, with the DL FX power plenum on a .25 DreamPup you could very likely get in the ballpark of 875 to 890fps with a JSB King Heavy 33.95 (MKI or MKII). Without any other mods just the DL 17cc Plenum with good tuning I’m thinking more like 850 - 860fps realistically. With similar power modifications to mine you never know... You may be able to reach 900fps?