bb dropping
 

Hi, I recently bought a dboys akms and am having some issues with the hop up (i think) which doesnt seem to be working very well or at all. no matter what i set it to they are curving down after about 100ft. on my other dboys ak when i fool around with the hop up i should get bbs going up, down, sideways and if its in the sweet spot straight but in this case its always 100ft then down so im lost

What does it chrono?

no clue i dont own one. i have another hop up i might try out today

Well if the problem is that your gun only shoots 120fps, then it's not your hopup unit thats the problem...

im getting a good speed coming out of the barrel though it seems. the bb is just sharpy arcing down after 100ft thats why i think the hop up is off. i can adjust the hop up too and i get the exact same result everytime

Is it a brand newgun or did you buy it used? Sounds like your hop up bucking is missing or broken, your hop up settings should cover the full range of BBs roll out of the barrel when full off, and when full on send your BBs skyward. If you can't get either of those two to happen, your hop up rubber needs looking at.

He'd still have variation with the different setting at any fps.


You need a new rubber and/or bucking, or possibly worst, the arm on you hopup unit is broken and it needs to be replaced. You'll have to have a look at it.

well i just had the gun apart for the 4th time and checked everything out. hop up looks good, rubber looks good (compared it against an older one i had). everything was super oily though and i heard that can effect the accuracy so i cleaned everything up. just charging the battery now to check it out. if there is one problem that it still might have it doesnt look like the piece at the end of the hop up arm is pushing down hard enough on the rubber to depress the nub into the barrel to put the backspin on the bb. the actual plastic hop up unit looks ok though

the gun is "new" as far as i know. it was bought from someone who bought it from an importer who bought it new from a site and apparently its never been fired. it did have some signs of use though, the body pin is whacked into the slot so hard i cant get it out and there are some small scratches and minor rust spots on the interior. all else is spotless

How oily is everything, as in the hop up? I think you may have found your problem, an oily hop up rubber is a useless hop up rubber....... because of no friction. It may take a few hundred shots to get the oil worn off, but you could take it out and wash with dish soap, reinstall, put one drop of oil down the feed tube, cycle a few times, then run a few mags through. A perfectly non-oiled hop up rubber is worse than a really oily one, because the BBs jam. Find the balance. ;)

ok so the problem has been solved. i removed the oil from the inside of the hop up chamber and realized i was missing the piece of rubber tube that depresses the nub so i added a new one and its shooting great and straight

That piece is called the bucking.

Bingo, I win. Lol

thanks for the help alls of ya!!