TM MP7 BB feeding issues & battery issues

[Brockavich]

Noob question:

I just got my TM MP7 and I have some issues...

Whenever I feed a fully loaded magazine into the gun it fails to fire BBs on either full auto or semi auto. It will maybe fire 1 BB out of every 20 shots. If I hold the gun upside down (I know you shouldn't do that, but I had to do it to see what it would do) it fires nearly flawlessly. I tried it using 3 different magazines and all 3 magazines fail to fire properly. The battery is fully charged too.

I don't think there's any BBs in the barrel, because if there was, it wouldn't fire at all right? The fact that the latter two magazines don't work might be because they're crappy at feeding anyways, but the fact that all 3 behave pretty much the same is worrisome.

for tl;dr:

My MP7, full charge, not on safe, fully loaded magazines (3 different types) all fail to fire BBs like they should. It fires about 1 BB every 20 pulls of the trigger or 20 shots.



As for the battery:

I charge it for about 1 hour and 45 minutes. I've been told that's roughly a full charge. Question: is it better for the battery to completely drain it (as in make it so it doesn't have enough power to fire a single BB) or does that not matter?

Is there a "best" way to charge and take care of the battery?


Thank you so much and sorry for the 20 questions

[ujiro]

Does it work when you hold the mag up into the magwell, like push it upwards?

[Brockavich]

No I tried that and nothing. There's no wiggle at all in the magazine either

[ujiro]

But holding it upside down works? Sounds like the mags feeding springs are crappy and aren't pushing the BBs up properly. Maybe missing the follower too, although thats less likely and I dont think would cause this. Maybe some slight obstruction in the feeding canal of the hop-up unit too...

Does it repeatedly feed when you flip it upside down? Like for as many rounds as you want?

Edit: if you battery is a NiMH, then you don't ahve to worry about discharging it before charging it.
Also, undercharged battery wouldn't cause feeding issues.

[Brockavich]

Hold on I'll check

[Brockavich]

Okay well the battery is Nickel Cadium (NiCd) so do I have to have to make sure it's dead? Is it bad to leave any charge in the battery?

Also, I just tried what you asked and it doesn't shoot 100% normal upside down, but it shoots better, that's for sure.

I think ill go do more conclusive tests with my other magazines tomorrow if I can for sure, but what are some other possibilities if it's not the magazines?

[ujiro]

Other possibilities are pretty tricky. Feeding issues are difficult to solve, and are sometimes quite complex.

I would say for now worry about finding out if its just the mags, because mags are the simplest culprit. After that, hopefully others can give some good insight too.

And yes, to my knowledge, NiCd batteries must be discharged fully, and not left with charge in them, otherwise they get "cell memory", and the total storage and health of the battery can be greatly reduced.

[Brockavich]

Okay... I'll try testing the mags out more extensively tomorrow...

And I'll make as much an effort as I can to completely use the battery as much as I can


Thanks dude

[ujiro]

No problem. Sorry I couldn't be much more help, I still need to get better at diagnosing feeding issues, but a lot of times it is just the mag. There are lots of threads here about misfeeding guns.. You ought to check them out too to see what solved their problems and what other people suggested for some help as well.

[TokyoSeven]

Its a shot in the dark but maybe try dialing your hopup all the way down and then see if anything feeds correctly. This may not help but its worth a shot, if your gun is feeding properly when its upside down Im not sure what could be the issue.

As for charging the battery, if you have a secondary nice high quality charger, you could chop the ends off you MP7 battery charger, figure out your neg and positive wires and feed them into your other charger for nice monitored controlled charging. If not, just make sure you check the charging rate on your MP7 Battery charger, if the charger says 200MAH an hour and the battery is 500MAThen you would charger for about 2 1/2 hours.
Basically you divided the charging MAH into the battery mah to figure out time.

[Brockavich]

O_O I think I'll try for the latter of the two.

But just so everyone's aware. This thing has fired properly before. I have gone thru at least 10 mags just fine... It's only recently that this started.

But thanks for the tip anyways Tokyo... I'll try and shove a finger into that tiny little space where the hopup is

[Brockavich]

Okay, everyone will be relieved to hear that it was the magazine.

It turns out the magazine that came with the gun, the one I thought was more reliable, was the only one failing. The two high caps work fine. Yet I always thought they were crap.

Learn something new everyday.


Anyways THANK YOU to anyone who responded. +1 e-***** for you

[ujiro]

hahah. no problem man, happy to hear it was a simple problem! Like I said, magazines are most often the culprit!