Trigger master in a full-auto only gun

[PoFF]

I was reading about the trigger master and from what I see, it does offer alot of options for trigger settings (semi, burst, auto, and combinations of these three), but it also regulates power and "soft-starts" the motor when the trigger is pulled.

I've been having problems with my M249 for a while now (ROF too high, and the motor "hard starts" so it's quite hard on the gears, even with 8.4V, i've been stripping countless sets of gears & pistons), and was wondering if such an item would maybe help me slolve a few problems.

Is there a way with the triggermaster to 'regulate' & tune in the voltage that's going to the motor in order to adjust the ROF?

[ThunderCactus]

With a TM you can reduce the speed of your motor in 10% increments
I run my M4 with a 9.6v battery at 90% speed

[DonP]

It does indeed do exactly those things .

Also the trigger switches in an M249 style fullauto-only mechbox really take a beating too since they directly switch the full motor load. But after installing a Trigger Master unit there is basically zero strain on the trigger contacts afterwards because the switch is no longer carrying the full motor load every time you pull it. You can even replace the trigger switch with just about any microswitch that will fit in the gun, no need to source those crazy 15A-25A switches any longer since it only carries a few milliamps at most after installing a Trigger Master unit.

[CDN_Stalker]

I tried for a good week to install a basic/original TM into a CA M249 and couldn't get it to work at all, it'd start shooting as soon as I plugged in the battery, and wouldn't stop til I disconnected the battery. Also when it'd cycle, it'd be all in stutter mode, not full bore normal full auto. I never solved the problem, even though I had Don involved, we couldn't figure it out, so I took the burst computer I was given (I think it was bought from RedWolf) out of my MP5SD and tried it, worked like a charm in the 249, so I traded between the guns. So I can't offer a fix to the install of a Trigger Master in a 249, just my experience of trying. This 249 is heavily modified though as far as wiring goes (custom wiring to make the boxmag wind while the gun is cycling, etc), so I don't know if any of this is the problem.

[DonP]

I remember that now - that was a long time ago. I'd love to revisit that M249 if it's still about. I'll pay for shipping if you're willing to send me the gearbox/switch assembly. I'm sure that mystery can be solved. PM me and I'll give you all the details. There is no reason (well, no good reason) that a Trigger Master should not work with your gun.

Anyway, on a related note, if you experience "stuttering" fire then it is virtually guaranteed to be a malfunctioning trigger switch. (As in, when pressed ON it doesn't actually STAY ON.)

It would not be the first time a malfunctioning switch is discovered in an M249.

Here's the messed-up part: When the gun is stock-wired (or used with a MOSFET switch that doesn't have active braking) there often is not an obvious problem because the motor "coasts though" the dead spots in the switch connection until the power picks back up when contact is made again! (The dead spots are usually very short.) But this is inefficient, and not only does performance suffer but the contacts in the switch will arc like crazy and worsen the problem over time.

When a malfunctioning switch is used with a MOSFET unit that has active braking (like the Trigger Master), you can see this problem because your gun will "stutter" when firing. What is happening is that when the trigger switch hits a dead spot (which should not exist in a working switch) the motor is immediately stopped. Then it starts again when contact is re-made. When this happens quickly (several times per second) it feels and sounds like a "stutter". It's because with the MOSFET your gun is now fast enough to notice the bad connection the trigger is making.

For an M249 the bad news is that that bad trigger switch is now a problem. The good news is that it can now be easily be replaced with any old low-power switch that will fit, and you'll notice a performance increase because your power no longer has to bottleneck through a malfunctioning switch with dead spots in the connection.

Note: In almost a year and a half now of having Trigger Masters put into all sorts of guns, "stuttering" problems that turned out to be related to poor electrical switch connections: 100%

[PoFF]

Well, this was quite convincing, just ordered mine...!

However, quick question here, I was reading the installation procedure, and the part "fire 5 shots in semi-auto to train the device's timing", how am I going to do so with a FA-Only gun (or does it even matter to train timing on a FA-only gun?)

[DonP]

They just don't apply (and doesn't matter on a gun like the M249). There is no need to fire the first 5 shots after powerup in semi-auto to train timing on a FA only gun.

[PoFF]

Great! I just can't wait to get my TM (might even get extras for my other AEGs if things work fine.)

Is the delivery of those is still to be expected end-of-may / early june?

[DonP]

Yep, I'll have more after this weekend (month end). Those who have already ordered (like you) get their orders filled first, before they are officially back in stock. You'll get a notice when it ships, and delivery within Canada takes only a few days.

[ThunderCactus]

The first 5 shots also trains your burst fire timing, so don't expect to use burst fire either
There's alot of room in the 249 so atleast wiring shouldn't be an issue at all

[DonP]

Originally Posted by ThunderCactus

The first 5 shots also trains your burst fire timing, so don't expect to use burst fire either

Burst fire is actually the only thing the timing is used for. (Semi-only is basically "1-shot bursts")

However you can always manually adjust the default values if you want with the advanced configuration (same options that let you set motor speed, etc.) The gun just can't auto-train it if there is no semi-auto on your mechbox.

There are two basic things the M249 (or any full-auto only gun) can't do:

1. Use any firing mode that needs the gun to be on SEMI on the selector (the gun acts like it's always on FULL)
2. Automatically train for the timing (which needs you to be in SEMI, which doesn't exist)

Since it looks like there is some interest about the details of a Trigger Master in an M249, here is the complete rundown of what you give up by not having semi-auto (forgive the graphic, I don't think there is a way to do tables in a post):

[pilotguy]

Well.. Not that you need anymore convincing but...

Just so you know, the TM is .. as I like to say.. THE SEX! My good Lord that trigger master is amazing!! Got the wire set with mine too and did the full rewire of my gearbox. Easy and simple, great quality wires provided too. Plugged my battery in and felt the vibration I have now come to love hearing. It's my AEG telling me it's ready to start blazing the enemy!! By far the absolute best purchase so far in 2009. What really amazed me and has had the attention of anyone who has fired my AEG is the instant trigger response. Not the normal squeeze the trigger 3/4 of the way before it fires.. Nope this bloody thing is like a hair trigger now. Just awesome!! No more half cocked spring either when your battery decides to quit on you. The TM wins again by cutting the tired little fella off when it needs a recharge. Soft starts and active braking... the list goes on. I'm upgrading another gun of mine next week with my other mosfet and installing one for a friend of mine too shortly.

Thanks DonP!! TM kicks ass!

[DonP]

You're welcome! Glad I could help!