Matrix (S&T/AGM) MG42 - In-depth Look / Upgrade Blog

[Rawbbeh]

509mm barrel eh? Looks like I know my next upgrade. My tech guy even said that the stock barrel was junk and too long but didnt have "long" inner barrel in stock at the shop. Of course we happen to be talking about the issue with the barrel practically the same day you guys mention it as well. I think dropping it down to the Madbull 6.03mm x 509mm long barrel would be beneficial...especially since the stock one is junk.

I did get to play with my gun yesterday after all the other work had been done on it...my tech went as far as to fill in the underside of the plastic BB loading tub that the Box Mag feeding spring inserts into with hotglue to add some weight and he leveled it out on the bottom and added velcro to the underside of it as well as the metal tray that it sits on top of in the body of the gun... If you remember KenTsui i mentioned how the spring would pop out and i was having the use some duct tape to hold the feeding tube spring in place? Yeah...not anymore!

The shimming on the hopup worked real well, infact, he also took out the big spring that applied pressure on the hop up as that wasnt necessary after he worked on it.

I used my MG42 at a game yesterday for the first time since all the work...No problems with it firing, no problems with the box mag feeding or loading, trigger works great winding and firing the gun...overall just great performance thus far. Next step is installing a new barrel and probably adding some electrical tape around the barrel at various parts to keep vibration down and support the barrel with the help of the outer barrel.

[Rawbbeh]

Oh, lastly, KenTsui:

Do you have a link of the correct MG42 sling I need to purchase? You say to get a late production sling...if you can point me in the right direction that would be so great of you!

[KenTsui]

Originally Posted by Rawbbeh

Oh, lastly, KenTsui:

Do you have a link of the correct MG42 sling I need to purchase? You say to get a late production sling...if you can point me in the right direction that would be so great of you!

This is where I bought it. It's not necessary the best place to do it, but after wasting money on the incorrect one, I took a gamble here, and it paid off.

http://www.epicmilitaria.com/product...-leather-sling

The late production of the MG42 slings fit both the MG34 and MG42, but the early production models only fit the MG34. So just because it fits the MG34, doesn't mean it fits the MG42.

It's difficult to tell whether it'll fit or not from online pictures. The first one I bought said "MG42/34" sling but it was in fact, the narrower version.

[Rafter_Man]

I took the time to take some pictures of the mods I did to the boxmag. I rewired it just like you did KenTsui, because, lets face it, priming the mag is awsome ^^ who wants to dry fire that beast? No one.
And because i hate rattling I also cut up a pc noise absorber matt and lined the inside of the boxmag with it. Works pretty well and it is alot quieter than before. Also You inspired me to cut up some dummy rounds and put them over the feeding tube. I dusted them metallic black to look more like german WW2 steal casings which where painted black.







Also Kentsui check you ammo links on the feeding tray insert. It looks like you put them on upside down.

[KenTsui]

Originally Posted by Rafter_Man

I took the time to take some pictures of the mods I did to the boxmag. I rewired it just like you did KenTsui, because, lets face it, priming the mag is awsome ^^ who wants to dry fire that beast? No one.
And because i hate rattling I also cut up a pc noise absorber matt and lined the inside of the boxmag with it. Works pretty well and it is alot quieter than before. Also You inspired me to cut up some dummy rounds and put them over the feeding tube. I dusted them metallic black to look more like german WW2 steal casings which where painted black.







Also Kentsui check you ammo links on the feeding tray insert. It looks like you put them on upside down.

Hey, great idea with the lining. I hate the rattling too, although it should in theory reduce the ammo capacity. What's another 100 rounds when you got 2000+ rounds, right? :lol:

OMG, obviously I haven't done enough research. Thanks for the correction on the direction of the link.

[Psquiddy]

Have you (or anyone else) had any luck in removing the feed tray of your MG? I'm converting mine into a MG3, and I need to remove it to install a RS MG3 feed tray (so I can mount the box magazine). Also, from the looks of it, the motor is a short-type? Would you say it would last a while, or should I go about replacing it with a nicer high-torque motor? Thanks for your time, and beautiful build!

[KenTsui]

Originally Posted by Psquiddy

Have you (or anyone else) had any luck in removing the feed tray of your MG? I'm converting mine into a MG3, and I need to remove it to install a RS MG3 feed tray (so I can mount the box magazine). Also, from the looks of it, the motor is a short-type? Would you say it would last a while, or should I go about replacing it with a nicer high-torque motor? Thanks for your time, and beautiful build!

Though I haven't tried, I've been told that the tray and top cover is held by a pin. A tap with the hammer should get it out. Carefully study the pin before you do so. If memory serves, you might need to rotate it so that it clears.

Yes, it is indeed a short-type motor. I never really studied it that closely but I would think it's consistent with most stock AGM AEG motors.

If you are not doing any kind of crazy build, there's no reason you can't keep using the stock one.

[Psquiddy]

Originally Posted by KenTsui

Though I haven't tried, I've been told that the tray and top cover is held by a pin. A tap with the hammer should get it out. Carefully study the pin before you do so. If memory serves, you might need to rotate it so that it clears.

Yes, it is indeed a short-type motor. I never really studied it that closely but I would think it's consistent with most stock AGM AEG motors.

If you are not doing any kind of crazy build, there's no reason you can't keep using the stock one.

I was asking about the motor since I've noticed that mine heats up considerably from sustained fire (out of the box my gun is shooting 450 FPS). More so when I use a 9.6v Nimh over my 7.4 Lipos, I get a ROF boost but my motor heats up quite a bit more.

[KenTsui]

Originally Posted by Psquiddy

I was asking about the motor since I've noticed that mine heats up considerably from sustained fire (out of the box my gun is shooting 450 FPS). More so when I use a 9.6v Nimh over my 7.4 Lipos, I get a ROF boost but my motor heats up quite a bit more.

Woah. Mine was shooting way less than 450 fps in stock form. If someone upgraded it with a stronger spring, that could add load to the motor and if the stock motor is not strong enough for that spring, it could add heat. I'd stick with the lipo since they generally have higher discharge rate, avoiding chances of starving the motor.

I personally haven't used the stock motor that much, so I can't really be of help with the specifics.

In my report, I mentioned several of things I did to improve efficiency in the gearbox. I noticed these things partly because I measured the efficiency of the gun using a watt-meter and it wasn't where I had expected. Every little thing added up to a couple of rounds per second improvement, a drop of couple amps, and conceivably, less load on the motor.

[Psquiddy]

Originally Posted by KenTsui

Woah. Mine was shooting way less than 450 fps in stock form. If someone upgraded it with a stronger spring, that could add load to the motor and if the stock motor is not strong enough for that spring, it could add heat. I'd stick with the lipo since they generally have higher discharge rate, avoiding chances of starving the motor.

I personally haven't used the stock motor that much, so I can't really be of help with the specifics.

In my report, I mentioned several of things I did to improve efficiency in the gearbox. I noticed these things partly because I measured the efficiency of the gun using a watt-meter and it wasn't where I had expected. Every little thing added up to a couple of rounds per second improvement, a drop of couple amps, and conceivably, less load on the motor.

What do you mean by starving the motor? And wouldn't a higher discharge rate mean a higher ROF? Or am I getting things confused?

[KenTsui]

Sorry for confusing you. Maybe I shouldn't have added that part since it has little to do with motor heat.

What I meant was that lipo's generally have a higher discharge rate (unless you're using a really bad one), meaning it will more likely supply enough amperage to keep up with the motor.

Higher discharge rate doesn't necessarily mean higher ROF unless the other battery you are comparing the lipo with doesn't have enough juice to keep up with the motor's demands.


For example:

Suppose battery #1 can output 10 amps and your motor needs 15 amps. Your motor is "starving" because it doesn't get the 15 amps that it needs. The result is reduced rof.

Swap it for battery #2, which can output 20 amps, then your motor is happy and you will see a higher rof.

Had battery #1 been able to output 15 amps or more, then you wouldn't see any difference when you put in battery #2.

[Psquiddy]

Originally Posted by KenTsui

Sorry for confusing you. Maybe I shouldn't have added that part since it has little to do with motor heat.

What I meant was that lipo's generally have a higher discharge rate (unless you're using a really bad one), meaning it will more likely supply enough amperage to keep up with the motor.

Higher discharge rate doesn't necessarily mean higher ROF unless the other battery you are comparing the lipo with doesn't have enough juice to keep up with the motor's demands.


For example:

Suppose battery #1 can output 10 amps and your motor needs 15 amps. Your motor is "starving" because it doesn't get the 15 amps that it needs. The result is reduced rof.

Swap it for battery #2, which can output 20 amps, then your motor is happy and you will see a higher rof.

Had battery #1 been able to output 15 amps or more, then you wouldn't see any difference when you put in battery #2.

So maybe the amperage of my Lipos isn't enough, since there is a very noticeable difference in gun performance when I switch batteries?

[KenTsui]

Originally Posted by Psquiddy

So maybe the amperage of my Lipos isn't enough, since there is a very noticeable difference in gun performance when I switch batteries?

The only way to know for sure is to measure the amp draw of the gun.

[Psquiddy]

I've recently aquired everything I need to SMP my MG42, but I have to resolder my trigger contacts for the installation. Do you have any idea where I could get a spare set, if I decide to go back to the original AEG design?

[KenTsui]

Originally Posted by Psquiddy

I've recently aquired everything I need to SMP my MG42, but I have to resolder my trigger contacts for the installation. Do you have any idea where I could get a spare set, if I decide to go back to the original AEG design?

Sorry, I'm not familiar with the SMP. How do you manage to fit the trigger board into the MG42's gearbox? If it's simple re-soldering, couldn't you reuse it?