Hop-Up

[sirtaco27]

Okay. I've had my JG M4 for about a month now, but I have a problem. I have no idea what the hop-up is. Sometimes I think it's okay but then it shoots straight up at a hundred feet. I'm thinking it's the .20g BB's I've been using. Help?

[chaosnemesis]

There's a "dial" behind the dust cover right above the magazine well on the right side of the gun. that dial turns to get either more hop or less hop.

When the bb hits the hop-up it imparts backspin causing the bb to rise up. Right now there's way to much hop so try dialing down your hop-up

[venture]

before you dial it down, try .25 gram bbs and dial the hopup in for that weight bb. Range will improve.

[m102404]

Lighter BBs are more dramatically affected by hopup. 0.25g min...0.28/0.30's are better.

Pull back the dust cover and you'll see the little dial there. Clockwise puts more on, counter clockwise takes some off.

Sounds like you need to take some off. You want your shot to go straight out...then just drop at the end.

If you find that you're having a hard time setting it...some things to consider:
- quality BBs...BBBastard and Madbull ones are very consistent (size, weight and finish)
- different hopup rubber (if you're using the stock JG one it's pretty crappy)
---a good hopup rubber will grip each BB consistently and will have enough cushion/play so that you can put fine adjustments on how much is applied