prechamber questions HELP!!

can anyone give me some guidence? im putting together a .25 cal rifle, but i want to run the rifle remote. I was wondering, what size prechamber would be good? the prechamber would be where the valve is, and it would hold enough air for 1.5-2 shots so the valve wouldnt starve during shooting…thoughts on length? the im gonna use a JDS airman valve, and 62cu in tank. thanks for any help!!