Hatsan Flashpup.

The Hatsan brand regulator is rubbish I have many of them for my other Hasan guns no wonder they're SO CHEAP live and learn I guess. I bought a HUMA but haven't installed it yet into my woody Flashpup yet. BE AWARE there are TWO DIFFERENT size regulators for the FLASH PUPS depending whether or not your stock is the WOODEN or the SYNTHETIC. SAME DIFFERENCES FOR THE RIFLE VERSION. BUY THE CORRECT ONE!!! Yo!
 
I have the hatsan flashpup synthetic .25 that is unregulated. Brothersinair on YouTube has some awesome videos on the flashpup. I hear the huma reg is the way to go.my flashpup act's like its regulated so I personally don't feel the need to put a reg in mine.

Where does your like to be filled my .22 liked the 150-160 bar range
 
I put a Huma-Air regulator in my .25 cal Flash Pup. The device as far as I can tell works flawlessly. Right now I am tuned for FX 25.39gr pellets (I think these are pretty much the same as the FX 25.39s). My Reg is set at 140 and I have 2 and 1/4 turns out on my Hammer Spring. The stats I believe are great for an entry level gun as can be seen in the attached pic. I get about 25 consistent shots before the refill
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