I was told when I purchased my mp5 the metal mags were no good for the ultra elites and those real hard gels. Stick to the nylon mags if running those gels.
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Hi everyone, I installed the high torque motor and now the batteries are going dead faster than usual. Is that to be expected or is something else going on now?
More details required…… battery type, motor type, other internal/electrical mods 
You have posted a great breakdown of your blaster, but not specific about the actual brand of MOSFET, battery brand and ratings or specs on which motor you ended up fitting.
Hi @DocBob ,
The motor and battery are as below:
I have just checked the battery and it is at 10volts remaining but the motor won’t turn.
I would try my other battery but I killed it by hot swapping it on the charger in a rush at Donnybrook today
My thought it to fully charge the battery, try firing it and see if I have killed the motor.
If it works again down to 10volts back off the motor screw?
I have no idea what went wrong.
Any advice appreciated.
For one you are letting your battery dangerously low. Balance charge that up before you blow up. That should be 11-12v for a 3 cell Lipo. Run them too low and they are fucked.
I have no idea if that charger you are using is any good or not. There are bad chargers and knock offs out there. Put a multimeter on your balance lead and test. If you don’t know how ask.
People have got to understand that Lipo’s are not AA batteries that you can throw around everywhere. Understand them, do your research, it’s all over the net and you’ll never have a problem. Unless you crash a 2 meter foamie from 200ft up and it crosses the wires, made a nice little fire 
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BTW that Xforce charger looks shit, it charges through the balance lead.
Genuine Skyrc imax B6AC V2 Balance Charger For Ni-Cd Ni-Mh 1-6S LiPo | eBay
Hi @Maiphut,
I always charge up fully before use, this is the reading when the motor stopped working.
I only got three and a half games in which is a lot less than usual from my battery.
Roger on the lippo care and I will look into chargers. My current charger is streets ahead of those usb ones that come with some batteries though. Lol
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It’s all good, the USB ones that come with the blaster throw them in the bin. That X force one may aswell go in there too.
Lipos will push full power until they die for good from draining them too low below 3V per cell, so in your case with a 3 cell is 9V. I’d guess something wrong with your blaster binding it so look there. It don’t matter if charged up before use it’s how much work the battery has done during that time, if it has to do more work then it will drain more.
Check your blaster and spend some time reading the plethora of information about Lipos on the net and you’ll have 15 year old Lipos like me 
Not all survive though ask if you need more help.
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As @Maiphut commented, those are crap batteries, with a crap charger and those are dangerously low numbers for an 11.1V battery 
A correctly fully charged 11.1V done with a proper quality balance charger will actually output somewhere around 14 volts when charged properly.
The 10V output you have shown, along with the cheap tiny batteries is the whole cause of probable any issues that you might be experiencing with that blaster.
This is poor enough to effect FPS, ROF, Accuracy and feeding issues from the magazine.
Get yourself a proper TURNIGY battery, either single or nunchuck style deposit on your available space… and MOST importantly… a quality battery charger such as a SKY RC as recommended above 
Using this motor, with the modifications you have previously listed, combined with this battery will definitely lead to very poor performances, motor/battery overheating and extremely short battery life
It’s like building a Ferrari and then fitting a Briggs and Stratton power train……. just ain’t never gonna work 
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Just googled it and don’t look any better than using the USB charger 
Thanks @DocBob and @Maiphut ,
I will replace my batteries and charger ASAP.
I’m so frustrated with Gel Blaster retailers right now.
I sent my blaster back under warranty when I first bought it as the motor was too hot to touch after one magazine of gels and they replaced the motor, at that same time I returned the B3 charger that they sold me with the blaster as it died on first use. The X Force balance charger was supposed to be an upgrade and I paid extra for it.
I’m guessing that the batteries and charger have been a problem from the start, I even sent it to a tech and paid for them to fix it when it started happening again as I had made the upgrades so voided my warranty.
You would think that the retailer would know more than the average punter and not sell products that are not fit for their purpose.
Thanks again to the brains trust for giving me the advice that I needed.
Cheers.
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Try one of these are great for a battery, fit in AR buffer tube.
Turnigy Nano-tech 1200mah 11.1v 3cell 25-50c Li-on Battery – OP Force Delta Gel Blasters
Just check your Dimensions: 116x16x19mm battery size for the turnigy. Just doing some reading might not fit in your MP5. hmm but the Bigrrr one lists as 150x30x30 size so I dunno 
probably typo can’t be that big surely.
The Bigrrr battery has a basic 20c discharge rate so will struggle with upgrades like heavier springs etc. Not many options out there from a quick look.
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The other option would be to double up your Bigrrr batteries, I read that can be done on the MP5. That would give you more juice.
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Hi @Maiphut , thanks for the advice, I ordered the Turnigy Nano-tech 1200mah 11.1v 3cell 25-50c Li-on Battery. My MP5 is front wired so I should be able to fit it in the hand guard. If not I will attach a mock PEQ battery box to hold it. 
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Something funny is going on here. I was just reading through the thread.
In the picture it shows a bigrrr mosfet. Is it the bigrrr mosfet?? If so I have these on all my blasters some front wired and some rear. All bigrrr mosfets have mag prime. It’s a setting that can be switched on and off via a combo of selector movements and trigger pulls. If you are unable to put it into mag prime this could point to an overarching issue.
Now the only times I’ve experienced what you are describing with a bigrrr with batteries and wires getting hot was with one that had a damaged wire and a another where the wiring had broken near the motor spade connector and it wasn’t visible. Poor soldering can also affect their performance.
I have been able to run all sort of batteries with zero issues both 7.4v and 11.1v. Even super tiny batteries I have run in the handguard of my MCX rattler.
My gut is telling me even if you get a turnigy you will still have issues.
I know it will be a pain but make sure the wiring is spot on everywhere.
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I’m new to this forum, and for some reason I couldn’t make any post. But I am having similar issues with my LDT MP5 And hope someone here could give me some advice.
Out of the box it was shooting 180-200fps.
At first I just upgraded the spring, and manage to get around 250-260fps which is pretty reasonable. However, I noticed that while chrono, fps wasn’t consistent. It will be like 250+ > 260+ > 270+ then all of a sudden 160+ > 180+ > 200 > then back to 260+
On top of that, I also noticed some feeding issues.
At first I suspected that it was an air leak. I changed to a green O ring and a new nozzle head. Tested it definitely had good air seal. I also swapped to a stainless steel barrel 7.3mm
After wards, it was getting around 280-300fps, but it is still getting some random FPS drops.
However when I shoot it at full auto, it is shooting fairly accurately with a reasonably straight stream and tight spread. I have a hopup too
Any idea what could be causing the random FPS drop?
It’s using a nylon gearbox with metal gears. Considering to get a full metal receiver and LDX gearbox soon
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Biggest issue I found with the nylon gearbox version was cylinder to barrel volume ratio is a bit off being ideal. They really need a 60-70% cylinder to get consistent fps between shots.
Standard a lot came with the notched blowback cylinder which is closer to an 80%.
Also recommend disabling blowback for reliability.
Which LDT MP5 are we talking about? The MP5 or MP5K? 
As Roksolid said, getting your VE right is pretty crucial with these. If it’s a K, the LDT 80% cylinder isn’t well matched to the short barrel at all.
For reference, we put an upgraded MP5K fitted with a 70% cylinder through the chrono with three or four different barrel lengths… the longer the barrel, the higher the FPS.
Short standard MP5K barrel pushed around 210FPS then it stepped up incrementally to 280FPS with the longer MP5 A3 length barrel.
With the short barrel all the upgrades only gave a gain in FPS of about 20, but the same upgrades resulted in close to 60FPS gain wit the longer barrel length.
The solution was to integrate a length of inner barrel into a suppressor which gave BME the option of a lower powered shortie or a higher powered longer unit.
I completely agree that the stock LDT MP5 comes with a 80% cylinder, which is way too much for such a short inner barrel.
I would consider changing it to a 70% or even 60% once I get my hands on the LDX gearbox and a metal receiver. Right now its fully stock and I do dont see a point upgrading whichever one without the other since it has to be stripped down to the teeth anyway
LDX are easy enough to come by and are a good replacement gearbox in mp5.
I have a metal MP5, and it is only the upper receiver that is metal, lower is the same for both.
The metal version even though it is only the upper that is metal is very hefty.
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