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BYUrdneck
05-03-2008, 07:52 PM
Ok, so I recently cut down my stock barrel to 4" and am wondering what that will do to my FPS. With my new folding stock - it doesn't allow for adjusting the spring - so i can either cut it if it will be too much - or add washer spacers to boost it. The last time I played with it - I had a 12" barrel and I was shooting around 260 FPS. I am playing again on Tuesday and I do not want to have to waste a bunch of time getting my gun right and watch everybody else have fun. I guess in short - am i going to have to cut my spring or add some spacers because of the shortened barrel.

XSiv Force
05-03-2008, 07:58 PM
if anything i think youll need to add

slim and shady
05-03-2008, 09:03 PM
^Wrong answear Currly!

Because of the shortened langth of the barrel less air will be required to push it through. However im not sure how much of a difference you would see I dont think it would be very much. Your FPS may go up just slightly. Personaly I think you will be fine. I wouldnt add any spacers though or you probably will be over. If you have a few in already(when you had it shooting 260) you could even take one out if your worried you may be shooting a tad high and lose playing time

irishwarrior
05-04-2008, 05:44 AM
:yeahthat: Less barrel length=less friction=less air/force needed.

Prikasky
05-05-2008, 04:11 PM
dude you may have to turn up the pressure cause your barrel might be to short for the gasses to expand properly and get your rounds up to optimum velocity. ive never seen a four inch barrel so this reply is an assumption though from reading about barrels when i was shopping for one the sites all said things like too short or too long barrels are not gas efficient and i think that the best range was like 7-14 inches...

deano 177
05-05-2008, 04:23 PM
you will be fine. If you want to shoot 260 you'll probably need to turn the velocity adj screw out. You shouldn't have any issues with pressure.

BYUrdneck
05-07-2008, 07:48 AM
Ok, so I went and played and when I went to chrono, it came up as 220! I really didn't see that coming. So I added the only spacer I brought with me and it topped out around 255/260. So to get up to 275-280 I guess I will have to add some more spacers. Thanks for all the help guys.

Also - my 4" shorty barrel worked great! I was surprised by its accuracy. It worked great on the speedball course where I live. The paint did start to drop sooner (which was great for shallow bunkers) - but it was easy to make up for it, I even got some long distance hits with it!