WE SCAR H gbbr feeding on full auto only, totally stumped.

[XOIIO]

Hello all, I'm hoping that someone here can provide some input or maybe had a similar issue with their scar, as this really has me stuck.

My WE Scar H is double feeding when shooting full auto, and a lot of the time, once you let go of the trigger and tilt the barrel forward, it will actually have a bb fall out but one will be left in the hopup bucking.

The upgrades my scar has are a tan modify bucking, in good shape (a slight rip either side of the nub but nothing major), a 500mm 6.03 inner barrel, and an NPAS valve. My magazine feed lips are also shimmed however removing the shims did not help.

I just finished changing my nozzle out for a brand new one in case the little bit of a nick out of it was causing this, as one bb even ended up wedged near the top of the nozzle in the bolt carrier, and I noticed my npas valve had closed all the way, unfortunately correcting this and putting the new nozzle assembly in place did not fix this issue.

The gun still double fires, and I actually managed to have one bb hit another one mid air a few feet out of the gun and shoot either direction, which was cool, but annoying.

I've also tried stretching my recoil spring a bit, but that did not work and I recorded some slow motion video of the gun and it does not seem to have any bolt bounce.

My only theory left right now is somehow the nozzle is getting forced forward as the bolt is moving backwards but it did not look that way when firing, I suppose it could be too fast for me to see, I am hoping to try and get a slow motion shot when the sun is up higher, but that just seems unlikely to me.

The gun works great on semi auto and I can fire it very fast without this issue, The one other thing I can think of it being is maybe the trigger group? I was manually actuating it and I did see in some instances the hammer seemed to fall early, however doing this manually without it in the gun is far different to it actually firing.

Someone had also mentioned the bb perhaps being too far forward in the bucking but I don't think so, here's a picture of it regardless. https://i.imgur.com/rHaMoOb.jpg

If anyone has any ideas it would be incredibly helpful as I'm totally stumped as to this issue. It did work great before, unfortunately I didn't really do any extensive testing after putting in the 500mm barrel but I don't see how that could cause this, and I feel like I had checked full auto and it was good.

[kudougw]

check mag, it could be ur mag feed lip, when it gets too lose/wide open, it will release a bb when your nozzle travels back, and another when ur nozzle returns, thus 2 bb in a chamber per cycle.

[XOIIO]

Originally Posted by kudougw

check mag, it could be ur mag feed lip, when it gets too lose/wide open, it will release a bb when your nozzle travels back, and another when ur nozzle returns, thus 2 bb in a chamber per cycle.

Had a look at them and they are barely worn, which makes sense as they've been used relatively little, they still require a fair amount of force to put a bb in manually.

[kudougw]

try using a camera with slow motion, see if theres double bounce under full auto.

[edh]

i had a problem with my scar heavy when i got it nozzle broke just test firing it..replaced it with a ra tech metal one..and it still did not feed or sit well..had to put a piece of the soft side of velcro tape on the back of the mag well..now the mag sits perfect in line with the nozzle and feeds fine...now i just shot it some..i do not play airsoft..but it might help,you

[XOIIO]

Still have the issue and can't figure out a solution, have a new hopup bucking and no luck, the nozzle springs still have not arrived, and they only had one in stock it turned out.

Was hoping to swap the trigger group with someone else but I don't really see how that would cause this issue. I've been using the gun on semi auto only but it would be nice to have full auto as a backup, I've accidentally selected full auto a couple times by mistake and missed shots due to the double loading.