mightyjebus

well...this was meant to be a parts gun. I needed the internals for a project but looking at it I thought it could do with a different grip, stock and flash hider, then I thought maybe some accessories, oh and a bit of paint so now it's not a donor gun.
 

well...this was meant to be a parts gun. I needed the internals for a project but looking at it I thought it could do with a different grip, stock and flash hider, then I thought maybe some accessories, oh and a bit of paint so now it's not a donor gun.
 

I used the smoke silencer in anger today and had a blast. I really need to sort out a tracer as well as at one point I was in a dark corridor in a prison and firing semi with no idea if my BB's were hitting the target because of all the smoke and flash (this was a whole lot of fun and no I wasn't blind firing, I'd put the red dot on the target and fires a couple of BB's but fook knows if my BB's went on target as I couldn't see a thing because of the smoke and flash effect).
 
Oh and I seem to have ended up with a Spectna Arms Mk18 with the Gate mosfet fitted.

I'm going to do this review slightly differnetly from normal. Usually I'd take the AEG to bits and talk about the good and bad parts but there are plenty of youtube videos out there comparing the GBLS to other platforms and very little on what it is like to use one.
I'll cover the elephant in the room, the price, later on in the review and give my thoughts.
 

So this is my GBLS and I bought the budget/skeleton kit for a couple of reasons. As much as the full rifle is nice I was never going to keep the supplied rail and was probably always going to make my own verison (Mk18 ish in my case however this might change to a MK16 or L119A2 depending on what I finally settle on).
If you have been living under a rock a little bit about what the GBLS is might help..or not. It's not a GBB rifle but it uses a similar design, it's not really a typical AEG but it uses a similar design. Confused? Well the closest thing to it would probably be the TOP M4 shell ejecting M4 but the GBLS doesn't eject shells. 
 
Inside the lower receiver you will find the gearbox and in the pistol grip is the motor. In the upper receiver you will find full sized bolt. Inside the bolt is the piston head and spring. The way it works is you pull the charging handle to the rear and when you release it it pushes the bolt forward and chambers a BB in the hop unit. You pull the trigger and this releases the compressed spring which pushes air out the front of the bolt propelling the BB out the barrel. At the same time the gearbox kicks in and cycles the bolt again and loads another BB. If set to semi it does this once. If set to auto it does that until every BB is fired out the magazine and the bolt locks in the rear position and you then take out the mag, replace with a fresh mag and hit the bolt release which loads a BB in the hop.
 
I'm going to be aiming these next comments to people who have been skirmishing a while and use PTW's, GBB's and NGRS's. You know that way on a PTW you can get a quick double tap off quickly and both BB's will mostly likely hit the target. On the GBLS that's not going to happen. Well it will but you are going to have to train with it to get a grip with the recoil as after the first cycle of the bolt your aim will be off by quite a bit. You know the way when you full auto a GBB rifle and the FPS drops about 30 or 40 from the first shot to the 35th shot. Yeah that doesn't happen. The  FPS is consistant from BB 1 to BB 60. You know that sound and slight recoil you get when you fire a NGRS well that doesn't happen. You get a very nice kick and quite a loud sound as the bolt slams forward.
 
I'm not having a go at these other platforms as I have them all and enjoy them but the GBLS is just a bit different and in a good way.
 
I'll do a few more comparisons to the other platforms so that the more experienced players get where I'm coming from. On the GBB it's great to have the bolt lock back making you do a mag swap, slap the bolt release and get back in the game. When I run a GBB (MWS, GHK, VFC, or any of the others I run) I'm always concerned that the gas I'm using which was under the site limits at the start of the day is now pushing the BB's above the site limit because it's now the afternoon and it's 10 degrees hotter. I'm also concerned that in the colder months in the UK I'm not getting the best from the platform because it's cold so tend not to use them.
The GBLS gives me the mag swaps and the recoil I get from my GBB's but at a consistant FPS the whole year. The recoil is probably just as good as my MWS running sub 350 FPS and if there is a difference it's hardly noticable.
 
On the PTW or a NGRS with a Titan fitted I get some nice snappy shots off. I don't get this on the GBLS. My first shot is snappy and on target but the 2nd shot will need adjusting (GBB people will know what I'm talking about). On the GBLS the trigger pull feels very real. I've heard that the trigger pull was about 10 lb but mine seems to be about 8. It feels very realistic with a nice break and reset. It feels more realistic than my GBB's never mind the PTW and NGRS.
 
My opinion at the moment is the GBLS DAS is more realistic than a PTW or NGRS and more reliable than a GBB.
 
Before I move on to price I'll mention the following. I ordered 2 Nupol 11.1V 30C Lipoi batteries as I thought the GBLS might eat through a battery since it's shifting the heavy bolt back and forward. I used 16 full mags today on 1 battery and there is still plenty of juice left in it so it doesn't seem to be current hungry. I had zero jams, stoppages or feeding problems with the 8 mags I used (although I did loose one somewhere along with a Glock 19 but thats another story!).
I took it out the box, set the hop with 0.3g blaster BB's and was easily hitting 55 meters with accuracy and the FPS is running at around 320 (on a 0.2g BB). To be clear I have done nothing to it, straight out the box if fires flawlessly and that leads into the price.
 
So £1350 for a toy gun  is quite excessive or is it? Let's have a look at the other toys out there. Let's start with the GBB as this is probably the cheapest platform when comparing it to the rest unless you look at the running costs over a long period of time. So a MWS is around £500 then you add 7 more mags at £45 a pop. Let's also remember that carrying 8 BGG mags is a chore as they weigh a ton. Let's say you want to get the best range out to 55/60 meters so you might chuck in a tightbore and maple leaf rubber and possibly a NPAS to control the FPS. So you are probably looking at about a grand now.
 
TM NGRS can be a bit of a money pit when it comes to getting the best out of them. £550 for the AEG, £150 for the titan, 8 mags at £25 each, tightbore, S hop, new spring and spring guide and possibly reinforced gears to replace the soft TM gears. We are probably at around £1200 now.
 
PTW's are anywhere from £1200 to £2000 depending on the model you buy but then you have spare mags, possibly get the hop sorted, have the electrics waterproofed and then maybe have the motor rewired. God knows the final price of a full tuned PTW. I hate to think how much I've spent over the years on them.
 
At this point you might be seeing the point I'm trying to make. £1350 plus £35 a mag doesn't seem that expensive when you don't have to upgrade/replace/rewire anything and it justs works as advertised out the box and is more realisitc and reliably than the other platforms. Are there any negatives? I know of 1 and heard of another but never experienced it. The electronic board in the gearbox doesn't like to get wet or so I have heard. Tell me a titan or Systema board that does. My only slight gripe is the metal mags rattle a bit inside the magwell. This is genuinely the only negative I could find with the GBLS.
 
Is it the best airsoft gun in the world? well no but it is the most reliably realistic one out there and it's very much a nice experience using it. 
 
I'll finish this review of with a couple of notes. I handed it to about 10 team mates today and everyone had a stupid smile on their face after that first shot. I think a few AEG's will be getting sold off shortly to fund a GBLS. I'm probably going to be one of the ones selling other AEG's as I see that there is now a HK 416 GBLS.
 
I'm not in anyway associated with GBLS but if you want to send me the steel bolt and Type B buffer I'm not going to get upset. Just saying.

I was planning on writing this after using it in a game but I got man-flu so obviously I was dying and couldn't make the game day but I'll do a mini-review anyway since I've been messing around with it and put about 20 mags worth through it.
 
A bit about the Real Steel version:
“APC” is an acronym for “Advanced Police Carbine.” The “K” stands for “Kurz,” or “short,” and “B&T” is the shortened name for Brügger & Thomet of Switzerland. The APC9 was introduced to Europe in 2011 in 9mm, and was quickly engineered for .40 S&W and .45 ACP offerings. The standard model's barrel length measured 7 inches and featured a right-side folding polymer stock. A carbine variant with a 16-inch barrel was also developed for the commercial market, as well as integrally suppressed models.
 
I've seen this advertised as the SCW-9 and the APC9 however if you follow the B&T naming convention this this is actually the B&T SMG ACP9 K PRO G. Which translates as a Sub Machine gun made by Brugger and Thormet called a Advanced Police Carbine in 9 x 19 mm calibre with a Kurz barrel with a Glock Magazine lower receiver and the PRO part is anyone's guess.
 
So there is now an airsoft GBB version of the B&T SMG ACP9 K PRO G made by Maruyama. Well I have no idea who Maruyama are and the box claims it was designed in Japan and built in Taiwan. Is this actually a VFC built GBB? It takes VFC style Glock Magazines but apart from that fact I don't see anything that screams out VFC. I think it might be a new company called Maruyama but I could be wrong and time will probably tell.

 
Ok, so on with the review. What do you get in the well packaged brown box? The GBB SMG, a 50 round magazine and a fake silencer/suppressor, oh and a little allen key to adjust the hop.

You might have noticed there are no markings on the SMG. I guess this is to get around any trademark issues outside of Japan.
 
The silencer is actually a inner barrel extension and has an effect on the FPS when attached. With the magazine filled with 144a gas and the magazine temperature at 21C, the FPS is 290 which is pretty consistant. By adding the silencer this jumps to 355 so you get a 70 FPS boost by fitting the silencer on average. As you can see below the silencer can be stripped down and the inner barrel removed if you want to keep the FPS down or add a tracer to the inside of the silencer. One thing to note is the silencer is very tight to get on and off. I think this is down to the paint and should become easier are the paint wears down over use.

I have a few different VFC glock magazines and they all fit and work fine. I actually prefer the Maruyama magazine over the VFC mags and in fact I just ordered some more as they are cheaper than the VFC 50 rounders and seem to work very well. The Maruyama mag works well in my VFC pistols just in case anyone was wondering. TM/WE/Raven mags don't fit this GBB.

VFC G19X mag in the GBB

VFC Glock 19 Gen 3 in the GBB
Adjusting the hop is easy and involves putting the supplied allen key in the hole in the front of the receiver and turning left or right to get the desired hop effect. The good news is that you don't need to disassemble the GBB to adjust and it can be done on the fly with a magazine loaded. The other plus side is the hop unit has no issues hopping 0.3g BB's and I've tried a bunch of different BB makes and had 0 jams, 0 splitting and 0 malfunctions. In fact I've had zero malfunctions with about 20 odd mags through it. It's a very reliable little GBB.

Inside the wear seems to be minimal after 20 odd magazines. I don't see anything to cause concern right now. 

wear near the barrel is minimal. The grey is a mixture of paint wear and grease.

the bolt front shows the same paint wear and grease

The rear of the bolt shows wear from hitting the buffer.

there is hardly a mark on the trigger group.
 
My conclusion:
Weirdly it didn't come with any iron sights as standard. You can't find B&T iron sights that easily so the closest will be the IWI polymer flip up sights if you want to run irons. I don't know why this bothers me so much
 
function and fitment are spot on. Zero complaints from me and it has a nice recoil to boot. Accuracy is about the same as a GBB pistol but slightly better as it has a stock attached. Range is decent but BB weight and gas used with vary the results.
 
Negatives: Probably spare internal parts long-term will be a problem and I wish the selector lever was metal instead of polymer but that's just nit-picking.
 
On the Mightjebus review scale it's a solid 4 out of 5.
 
p.s. The Omega 9 tri-lug tracer silencer fits and works very well on this GBB.

I have a simliar tale, didn't want to spend UK prices so about a week ago I got one from WGC for 363 quid shipped. When it turns up I'm expecting customs charges and if i'd only waited a week I could have picked it up from Bespoke for 350.

So I tested the AEG today using various weighted BB's and the results are:
0.2g upto and including 0.28g no problem with hop or overhop
0.3g upwards don't hop.
 
I'll probably run 0.28g BB's until I get around to S hopping the inner barrel. If you buy 1 and want to run heavier BB's then you will need to look at another hop rubber/bucking/hop unit to run the heavier BB's.
 
I also tried to measure the inner barrel as I'm curious to see what the inner diameter is however I ran into a couple of snags. The first being the flash hider. The grub screw that holds it on and the flash hider actually have thread lock on them. I wasn't expecting this for such a cheap AEG and is something normally seen on high end AEG's. I had to end up press fitting a star drive bit into the grub screw to get it out and used set of pipe pliers to get the flash hider off. This sounds like a negative but its not. It just means the build quality coming from DE is pretty high. You can see on the picture below the red residue of the threadlock on the inside of the flash hider.

 
Once I got the flash hider off I used my calipers to measure the inside of the inner barrel and got a weird reading of 7.4mm as I pushed the calipers in further it got smaller 6.4 until I couldn't fit the calipers in any further.
It turns out the inner barrel has a taper for the last 15mm of the inner barrel. Again this came as a surprise on such a low cost AEG.

 
I haven't stripped the gearbox yet but I did find this good photo on Taiwangun showing the internals.

 
I've pretty much set on this layout for now (apart from a 3D printed battery entender which is printing as I type this).


 
 
If anyone is interested it's now £104 on Taiwangun and this is a mental price for such a good little AEG. I'm tempted to go buy one of the longer models as I think this whole series from DE could be very good value for money.
 
*EDITED as I don't know which way a red dot goes on a rifle

https://www.thingiverse.com/thing:3782295

for those interested.
 
PXL_20230903_083748067.TS.mp4

for those interested.
 
PXL_20230903_083748067.TS.mp4

Glad the glasses are working out for you. I just had to order another 20 fans as I can't make them fast enough at the moment.

And this is probably a good point to get across in this topic. Leave first aid to trained professional if at all possible. If they need your help they will ask for it.
 
To give an example, an old bloke, not unlike myself, falls over and stops breathing. You arrive on the scene and decide to administer chest compressions after doing the ABC's. Now some of the older gentlemen on here will jump in with 15 and 2, some of the slightly younger peeps will go for straight compressions and the new kids on the block will be doing 30 and 2 as per the current guidelines. It turns out that it was in vain and the old fella never recovers. sad times all round.
 
Now, the old fella was a top bloke but his family turn out to be arseholes. All 3 options above showed a willingness to preserve life but only 1 was concurrent with the latest guidelines so anyone doing either of the first 2 could be liable to a negligence claim. probably most of you reading this will be thinking, "I'd do it anyway" which is the right answer but just remember the world is full of arseholes.
 
Also don't be handing out over the counter drugs to people as you have no idea of their medical history or what other medication they may have taken.

the pin looks like 3 possible things, the pin from the G36 mag release, the rear lower receiver on a glock or the lower receiver gearbox pin from an M4

And this is probably a good point to get across in this topic. Leave first aid to trained professional if at all possible. If they need your help they will ask for it.
 
To give an example, an old bloke, not unlike myself, falls over and stops breathing. You arrive on the scene and decide to administer chest compressions after doing the ABC's. Now some of the older gentlemen on here will jump in with 15 and 2, some of the slightly younger peeps will go for straight compressions and the new kids on the block will be doing 30 and 2 as per the current guidelines. It turns out that it was in vain and the old fella never recovers. sad times all round.
 
Now, the old fella was a top bloke but his family turn out to be arseholes. All 3 options above showed a willingness to preserve life but only 1 was concurrent with the latest guidelines so anyone doing either of the first 2 could be liable to a negligence claim. probably most of you reading this will be thinking, "I'd do it anyway" which is the right answer but just remember the world is full of arseholes.
 
Also don't be handing out over the counter drugs to people as you have no idea of their medical history or what other medication they may have taken.

And this is probably a good point to get across in this topic. Leave first aid to trained professional if at all possible. If they need your help they will ask for it.
 
To give an example, an old bloke, not unlike myself, falls over and stops breathing. You arrive on the scene and decide to administer chest compressions after doing the ABC's. Now some of the older gentlemen on here will jump in with 15 and 2, some of the slightly younger peeps will go for straight compressions and the new kids on the block will be doing 30 and 2 as per the current guidelines. It turns out that it was in vain and the old fella never recovers. sad times all round.
 
Now, the old fella was a top bloke but his family turn out to be arseholes. All 3 options above showed a willingness to preserve life but only 1 was concurrent with the latest guidelines so anyone doing either of the first 2 could be liable to a negligence claim. probably most of you reading this will be thinking, "I'd do it anyway" which is the right answer but just remember the world is full of arseholes.
 
Also don't be handing out over the counter drugs to people as you have no idea of their medical history or what other medication they may have taken.

Just go buy a MWS. get it out your system as they are really good. Just make sure you buy a Bavtac 140% nozzle return spring for when the TM one breaks (and it will eventually).
Once you get over the MWS start to have a look at something a bit more exotic like the GHK Sig 552/553 or the Archwick ACP9K (on pre-order now it seems). I've been running mostly gas guns this summer and if you find yourself at UCAP vendetta then feel free to ask for a shot of the GHK 552, ACP9K G, TM AKX or whatever I've decided to try out that day.

This is the one I use:
https://grabcad.com/library/airsoft-gearbox-v2-g-g-1#!
 
looking at your model it looks like the V2 will be too tall so you have to get creative

Going for the Tokyo Marui prototype look here. Mock up in 3D resin proved fruitful as I need to adjust the butt cap as it's a bit tight and the designer is an idiot and managed to design the mag release spring tension the wrong way so that it always dumps the mag instead of retaining it. These should be easy fixes. 


Anyone want to buy one when I'm finished?
 

took a break from the SP9 build and designed and printed a front end for the Saiga 12K as I'm running it CQB so need somewhere for a torch and front grip.
File can be found here for free:
https://www.thingiverse.com/thing:6127823
 

finished the main shape of the lower. working on the mag release (push button instead of paddle now) and just need to finsih off the bolt release lever and exactly where to make a hole for the fire selector. On the plus side the Scorpion mag fitted in the magwell first time which is a bonus.

 

folding flip sites fitted and working under spring tension. Fake bolt works however I need to add a rod and spring so that it moves forward under it's own power. The idea is for the bolt release to be manually engaged, like the real thing, to hold the bolt to the rear and then when released the bolt shoots forward.
Turns out I'm 4mm too wide on the receiver so I've spent some time thinning the parts down to the correct size. I'm working from pictures from the internet and a pair of calipers so it's never going to be the exact dimensions of the real thing (unless someone has a real one and wants to share the measurements  )
 
I tried converting the upper receiver STL file to STP so that I could get a rough price for CNC'ing but for some reason my Freecad conversion doesn't want to work on the companies program for STP files. I thought I'd see how much it would be to have it SLS printed in aluminium but that was around 500 quid to best I figure out the STL to STP thing.
Here's a few photos of the current progress on the too wide body. I'm printing the new parts now so I can continue to tweek the design.

The OP didn't mention if he usually does woodland or CQB but here's my thoughts on GBBR's. I have a few:
GHK SIG 552, GHK AKMS, TM AKX, VFC M4A1, VFC MP5SD, AGM M4, WE PDW, WE SCAR L, WE M4 CQB, Marayama ACP9K G Pro, TM MP7 x 2, KWA Scorpion, KWA Mac11, TM Siaga 12K and a Beretta SMG from 1987 which is more of a wallhanger. I did have a TM MWS but sold it a while back when I fell out with GBBR's but now think I need another or the DE clone. I've also got a couple of the GBBR 10/22's but I'll discount them from this waffle as they are set up for sniping.
I don't use GBBR's at woodland sites during walk on days simply because I'm outgunned or more accurately out ammo'd. I tend to use my TM recoils, KWA T10 or GBLS on those days and get a similar level or recoil to keep me happy.
When I use GBBR's it's mostly CQB sites and I don't run anything over .28 tracers as there doesn't seem to be a need. If I need more range the  I just get a bit closer. I tend to carry at a minimum 6 mags when using GBBR's as anything less means I'm half fighting and half reloading after running away.
I also carry at least one pistol speed loader and a fake grenade that is actually a gas can so I can top up my mags if needed.
 
I've fired quite a few RS rifles over the years and I'd say the recoil on a GBBR is similar to a 22 LR round. Some GBBR's do a better job of increasing the realism, for instance, the TM MP7 has the bolt smashing into the rear, right next to your ear and this increases your perception of the noise from firing but to everyone else it just sounds like a GBBR.
Firing hot can be an issue and I've found that using the Vorsk gas either number 6 on hot days or number 8 on colder days gets me through the chrono without issues. By using the different numbers I don't need to worry about fitting Npas's although in the WE GBBR's and 10/22's I've fitted Npas's.
 
Looking at reliability, the TM GBBR's all work perfectly if kept stock and you want to use up to .28's. If you decide to go for heavier ammo then you go into the modding world and it can go either way until you hit the right combination. What works for some people doesn't always work for others.
My GHK's both work very well stock and I'd put them as the same reliability as my TM's. Some people have had issues but my only issue has been with the GHK mag base plate falling off and loosing a spring and follower which was $8 to replace but still a pain in the arse. 
My VFC M4 again works all the time and it's a Gen1 version and I bought a bunch of spares, ready for it to collapse in a heap but I haven't needed to use any of the spares yet. The MP5SD took a bit of work and aftermarket parts to get it firing consistantly but now it's a steam train.
I've slated WE GBBR's before and all mine are Gen 1 closed bolt version and work ok'ish in good weather but the Mags are a terrible design. It's a clam shell design with the worlds biggest square o ring that you will need to eventually fill with silicon and wait 24 hours to see if it still leaks. I wouldn't recommend WE as a first GBBR simply because you could come away with negative feeling about GBBR's at the end of it.
My KWA scorpion is awesome and the MAC 11 will either work fantastically or vent all the gas depending on how it feel that day. 
 
I'm not sure if anyone else has mentioned maintenance but GBBR's require cleaning now and again to stop the working parts getting gummed up from dust, twigs, leaves, bits of chopped BB's etc. It's good practise to wipe the bolt and upper recess where the bolt travels down and re-lubricate along with cleaning the barrel and hop up chamber at least every couple of games. Just like the RS versions, grease attracts dust etc which can effect the function of a GBBR.
 
I was going to mention that the Marayama ACP9 G, the MPX and the up and coming ACP9 are all excellent little SMG's with the Marayama taking 50 round glock mags but you will probably end up buying a MWS

yes they do. I order RIF's now and again from them.

The OP didn't mention if he usually does woodland or CQB but here's my thoughts on GBBR's. I have a few:
GHK SIG 552, GHK AKMS, TM AKX, VFC M4A1, VFC MP5SD, AGM M4, WE PDW, WE SCAR L, WE M4 CQB, Marayama ACP9K G Pro, TM MP7 x 2, KWA Scorpion, KWA Mac11, TM Siaga 12K and a Beretta SMG from 1987 which is more of a wallhanger. I did have a TM MWS but sold it a while back when I fell out with GBBR's but now think I need another or the DE clone. I've also got a couple of the GBBR 10/22's but I'll discount them from this waffle as they are set up for sniping.
I don't use GBBR's at woodland sites during walk on days simply because I'm outgunned or more accurately out ammo'd. I tend to use my TM recoils, KWA T10 or GBLS on those days and get a similar level or recoil to keep me happy.
When I use GBBR's it's mostly CQB sites and I don't run anything over .28 tracers as there doesn't seem to be a need. If I need more range the  I just get a bit closer. I tend to carry at a minimum 6 mags when using GBBR's as anything less means I'm half fighting and half reloading after running away.
I also carry at least one pistol speed loader and a fake grenade that is actually a gas can so I can top up my mags if needed.
 
I've fired quite a few RS rifles over the years and I'd say the recoil on a GBBR is similar to a 22 LR round. Some GBBR's do a better job of increasing the realism, for instance, the TM MP7 has the bolt smashing into the rear, right next to your ear and this increases your perception of the noise from firing but to everyone else it just sounds like a GBBR.
Firing hot can be an issue and I've found that using the Vorsk gas either number 6 on hot days or number 8 on colder days gets me through the chrono without issues. By using the different numbers I don't need to worry about fitting Npas's although in the WE GBBR's and 10/22's I've fitted Npas's.
 
Looking at reliability, the TM GBBR's all work perfectly if kept stock and you want to use up to .28's. If you decide to go for heavier ammo then you go into the modding world and it can go either way until you hit the right combination. What works for some people doesn't always work for others.
My GHK's both work very well stock and I'd put them as the same reliability as my TM's. Some people have had issues but my only issue has been with the GHK mag base plate falling off and loosing a spring and follower which was $8 to replace but still a pain in the arse. 
My VFC M4 again works all the time and it's a Gen1 version and I bought a bunch of spares, ready for it to collapse in a heap but I haven't needed to use any of the spares yet. The MP5SD took a bit of work and aftermarket parts to get it firing consistantly but now it's a steam train.
I've slated WE GBBR's before and all mine are Gen 1 closed bolt version and work ok'ish in good weather but the Mags are a terrible design. It's a clam shell design with the worlds biggest square o ring that you will need to eventually fill with silicon and wait 24 hours to see if it still leaks. I wouldn't recommend WE as a first GBBR simply because you could come away with negative feeling about GBBR's at the end of it.
My KWA scorpion is awesome and the MAC 11 will either work fantastically or vent all the gas depending on how it feel that day. 
 
I'm not sure if anyone else has mentioned maintenance but GBBR's require cleaning now and again to stop the working parts getting gummed up from dust, twigs, leaves, bits of chopped BB's etc. It's good practise to wipe the bolt and upper recess where the bolt travels down and re-lubricate along with cleaning the barrel and hop up chamber at least every couple of games. Just like the RS versions, grease attracts dust etc which can effect the function of a GBBR.
 
I was going to mention that the Marayama ACP9 G, the MPX and the up and coming ACP9 are all excellent little SMG's with the Marayama taking 50 round glock mags but you will probably end up buying a MWS

The suppressor already exists by another company. check here:
https://topboosttoys.com/products/smoke-wolf-silencer
 
unless this is you?
 
anyway, cool idea and I might or might not have ordered one