UMG Question?
 

My UMG has a double feed problem in semi auto mode. I thought if I changed the tappet plate it would solve the issue but it did not. I kind of think it's the hop up but I cannot be sure without replacing it. Anyone have any idea what it could be.

Does the gun have modifications and upgrades? Yes? No? What is in it? What are the specs as it is now? Who made it? Was it ever opened up? If it was, why was it opened?

If you dont give details, nobody can guess.

I purchased the gun new I had the trouble after about two weeks while the gun was stock never opened. I wanted to do some up grades to improve FPS so I thought I would change the spring, piston and piston head. I did also purchase some steel bushings but I did not change them because I still need shims. Anyway I changed the tappet plate when I did the mods because I read that this could be the solution. I would like to say that it seemed that the problem started right after I adjusted the hop up for the first time. That's why I thought it might be the hop up.

If you put a high power spring in a gun with plastic bushings, it WILL fail. It will probably totally chew up your gears too.

Be more specific; what kind of spring did you put it, what is it's power rating?

Who makes that UMP? If it's a cheap chinese copy of a Marui or other established company, dont expect to be able to do much.

The UMG is made by G&G I do not believe Marui makes a UMP. Also the spring that I put in is a M100 which I believe will give me around 300-320 FPS. It seems to be running fine other then the double feeds in semi auto which was the same before the upgrades. Like I said I have the steel bushings and I will change them but I would like to get the double feed issue resolved.

If you have turned the hop-up all the way off, do you still have this problem? G&G is notorious for using lithium in the cylinder (worst crap there is). If any of this has migrated to the hop-up, that may be the cause of your problem as well. Swab out the barrel and hop-up with a cloth soaked in silicone oil. If it comes out any color other than clear, keep doing it until it comes out clean. Then try the gun with no hop and keep adjusting it and see what happens.

Okay, I dont know if G&G has metal bushings already in the gun or not. If it has plastic bushings, and you did not replace those when you installed the spring, the gun will fail real soon.
If the gun already had metal bushings of some type, you should be ok.

I strongly suggest you check what kind of bushings are in the gun before trying anything else. If it's plastic, your hopup will be the least of your problems.

They do not have metal bushings out of the box. I would know this since I have upgraded mine and have dealt with the double feed issue also. I replaced the hop-up (bucking & sleeve) which solved the problem with the double feed.

I replaced the plastic bushings with Guarder metal bushings (which are very very nice!) along with a PDI 170.

Also invest on quality batteries. Dont let people tell you that you need to do an external battery. Just do this.

Buy one or two 8.4v Intellect 1400 Mah stick batteries. They are great cells. I haven't once ran out of juice in the field in one of the batteries, and I have not needed to use the extra battery. Also to prove this fact, I play 6-8 hour skirmishes also using a hi-cap and never ever has a battery died.

Also I dont like the standards, they dont feed that great. So I am stuck with hi-caps (which I dont like, realism wise). Although it shouldn't matter if you dont use this gun for Woodland.

Overall this is my favorite airsoft gun I have ever owned (TM AK, TM AUG, TM G-Spec, TM SOC 16 [not sure if this will be my new favorite time will tell] ... pistols etc.).

-Blink

Thanks Blink43va could you tell me where I can get the parts to replace the Hop up? This is also my favorite gun looks just awsome G&G did a great job on the external parts just need to get the inside up to speed.

What are you looking for FPS wise?

I bought some of my stuff from www.airsoftextreme.com and I have bought other stuff from www.airsoftnw.com

-Blink