JnJ Porting question

[DRUMNATURAL]

I want to know how long the barrel is before the porting holes begin on a 12'' JnJ ceramic. I have a 14'' JnJ, my porting starts at 7 1/2 inchs down the barrel. I want to know where the 12'' starts. As of right now I'm thinking of covering some of the holes.

[speeddemon0016]

i have a 12inch and the porting starts 6 1/4 inches down the barrel.

[DRUMNATURAL]

cool thanks. You might want to cover the holes so they don't start so soon. I beleive that the paintball stops acclerating somewhere between 8-10 inchs down the barrel(someone please corret me if I am wrong), but the porting will also stop the acceleration. So by covering the holes up to a point, it should improve the performance of the barrel. Anyone please reply about this with any comments on this.

[Soyboy]

that's stupid if u cover up the wholes... who cares

[Dravion]

acctually the ball does start to loose some of it's exit velocity because gas is escaping through the holes... though I don't think an inch or so will make that much difference. Seeing as the velocity we measure the ball when it exits the barrel... which just means you'll have to turn your velocity down a little bit more than usual. as far as I know... so it's not stupid, just a bit pointless....

[july_favre]

test it out- cover an inch at a time and see how much the volocity changes each time.
IM trying to find a set of barrels with very little porting for my guns.

[Demolisher]

Anyone know what is the best way to cover up that porting, i also have a 12" j&j ceramic and have a problem with low fps, coverting the porting would help.

[speeddemon0016]

there are better ways to raise your fps.