it doesent shoot over 200 fps and weirdly i put a new battery in it and it turned on the next day said the battery was full i then pulled the trigger and it cut out but when i put a new battery in it worked please help
this problem could be caused by a number of things, i'm sure some more experieced techs will come on and run through the details soon but in the mean time you should just run through the basics:
reg pressure at 180-200 psi (guage on asa)
fresh battery (as you have already done)
strip and clean/ re lube the bolt and bolt guide (including poppet at back of bolt assembly)
screw the velocity adjuster all the way in (without air) then air the gun up and unscrew untill the velocity is sufficient (using a crono to be sure)
ensure that the air tank is screwed all the way into the asa otherwise the air supply to the gun will be minimal
when you shoot the gun without air and with eyes off can you hear the solenoid click?
And to follow soul snatchers good advice, if you have taken the bolt system out, make sure you have put the bolt spring back the correct way, it should click into place on the bolt, if it doesnt you have it the wrong way round.
If the mini has a tadeo board fitted. It is a capacitor which is shorting out on board. I had exactly same symptoms as yourself. Mini worked perfectly for about half hour max with new battery then shots started to drop off. If left over night turned off it wouldn't turn back on and drained battery fully.
I ended up fitting new standard board which didn't cost that much.