TM MP7 intermittent trigger issue

[WildBoneZ]

Hi All,

Brand new MP7 seems to have a bit of an issue where it doesn't want to fire,

If I cock it back with no magazine it will dry fire, however inserting the magazine in and cocking back I get nothing.

Happened to me before chrono today and lucky I had my back up as had no time to tinker, once I got home it cocked back and fired every single round with no stoppages.

no signs of bbs or anything else stuck in the barrel, only thought is I may have overfilled the mag with bbs but unsure.

Ive ordered an upgraded DCC industries sear as I've heard the stock TM ones can give issues.

Any advice appreciated! 

 

[Diablo675!]

What type of feeling do you get from the trigger? 
 

soft, squishy or does it just feel like a dead trigger? 
 

has the chassis been removed fully cleaned and lived lately? 
 

tm Mp7’s are known for intermittent working if they are over lubed. 
 

the seat sometimes fails and the steel sear is a good replacement if can find one. 

 

[WildBoneZ]

Soft and Squishy would be the best way to describe it actually.

Noticed the bolt/dust cover does not fully return when the issue happens as well.

Good advice I'll give it a good clean down and re lube.

 

[Diablo675!]

If it’s soft and squishy 

have a look on YouTube for a video that explains how to modify the hammer and check the sears. 
 

they are over moulded from factory so after time they give the feeling of the dead trigger 

yeah the chassis only needs very light greasing and the piston needs oiling every 20 mags or so for it to be decent.

 

[WildBoneZ]

Thank you mate, appreciate the information! 

 

[Decp369]

I’ve got a new mp7 & noticed similar issue with mine. I took out the nozzle & lubed up. When I reload & release the bolt it doesn’t go all the way forward therefore giving it a dead trigger. If you release the mag manually cock it then it works fine. 
 

One person did mention the gas freezing up some parts but don’t know if this is true. 
 

doesn’t happen all the time but obviously shouldn’t be happening at all

 

[WildBoneZ]

On night shift so had all the time in the world there to strip back to bare bones, relube and install the new upgraded sear, had a minor set back where a small spring flew across the office ?

Will be field testing tomorrow so hopefully all fixed!

FYI below video was incredible help and found the mp7 so be super simple to take apart! 

https://youtu.be/269yO4M-ToI?si=oQ_ctYKx-9p2Y_WP

View attachment 145215

 

[Decp369]

?? that’s what I hate about dismantling ! All the small parts that fly off everywhere. 
 

I seen that vid looks super helpful will have to order the part & fit it. 
 

let us know how you got on with it ?

 

[Diablo675!]

At least you found it. 
 

I made the stupid trigger spring fly on my first strip down….. 6 weeks later I received one from a HK site ? all for £4.99 

 

[WildBoneZ]

The tear down vid I was watching kept stressing about the springs flying off and I'm like okay,  I've got this.....

next thing I know I was on my hands and knees for about an hour in the office looking all over the place for it,

nearly gave up until I said to myself if I was a spring where the hell would I fly off too... ? 

Didn't get skirmishing today, was banjaxed so deff next weekend, but increased my confidence and understanding off the internals is half the fun for me! 

next upgrade maybe a new barrel and hop bucking but maybe don't need it!