[Swollen.D]

Hello there good people, I've finally decided to build the sleeper MP5! My favorite weapon from childhood video games: Cs 1.6 and Cs Source, specificaly MP5-A5 (Collapsible buttstock, triangular plastic handguard). I've been wanting to get one since 2014. I would like to know which MP5-A5 is the latest and greatest on the market & which upgrades should I opt for.
I want max out range since it will be replacing my M4. Things to note is there's no fps or joule limit. Want to use 0.30bb to 0.36bb max. Can and will extend inner barrer with the supressor.
So ya just let me know good base to start upgrading, spring to cylinder volume to bb weight ratio to max out range and speed, looking for at least 60 meters but more the better. Thanks!

This is how I want it to look.

 

[Doctor Jest]

Not a great platform to replace your M4 due to constraints on the size of the inner barrel, magazines, and cylinder, plus a lack of battery space, and the hop chamber isn't the best. It can be done but you'd have to replace a lot of parts which of course starts to push the price upwards. I'd also recommend some time spent learning about AEG tech work as even if you don't subsequently perform the work yourself there's a host of knowledge you can gain about which parts to use, which components are suited to certain builds, and all the other intricacies which preclude having to make threads - self-sufficiency my dude!

First lesson: There's more than one way to build an AEG to perform the task you've set out.

My MP5k will reach 60m (eventually) but it is 100% designed as a backup so as long as I can cover the range from point blank to my self-imposed MED then I am content. I wouldn't run an MP5, no matter how radically it had been modified, as a primary. For reference, it has 13:1 gears, a high torque motor, M120 (I think) spring, a full steel rack piston short-stroked by two teeth, and runs on an 11.1v 20C 1200 mah Lipo. The only other modifications I will be adding are a slightly longer tight bore barrel to push the FPS without any extra internal stress which should see the overall power rise to around 1j.

Which I'm 100% certain is far too low for your liking.

First question: How much power is your M4 putting out, and how much would you like?

Most of the builds out there are high ROF/CQB builds to take advantage of the form factor, not high FPS field builds where other rifles perform rather better. The more I consider this, the more I am convinced the battery will be a serious problem......turning over a mechbox that could be (for argument's sake) putting out over 2j is going to drain it in no time - and they are bastards to change out! I tend to leave mine in situ as the battery compartment is so tight.

 

[Doctor Jest]

Just for the sake of hilarity:

 

[Swollen.D]

Not a great platform to replace your M4 due to constraints on the size of the inner barrel, magazines, and cylinder, plus a lack of battery space, and the hop chamber isn't the best. It can be done but you'd have to replace a lot of parts which of course starts to push the price upwards. I'd also recommend some time spent learning about AEG tech work as even if you don't subsequently perform the work yourself there's a host of knowledge you can gain about which parts to use, which components are suited to certain builds, and all the other intricacies which preclude having to make threads - self-sufficiency my dude!

First lesson: There's more than one way to build an AEG to perform the task you've set out.

My MP5k will reach 60m (eventually) but it is 100% designed as a backup so as long as I can cover the range from point blank to my self-imposed MED then I am content. I wouldn't run an MP5, no matter how radically it had been modified, as a primary. For reference, it has 13:1 gears, a high torque motor, M120 (I think) spring, a full steel rack piston short-stroked by two teeth, and runs on an 11.1v 20C 1200 mah Lipo. The only other modifications I will be adding are a slightly longer tight bore barrel to push the FPS without any extra internal stress which should see the overall power rise to around 1j.

Which I'm 100% certain is far too low for your liking.

First question: How much power is your M4 putting out, and how much would you like?

Most of the builds out there are high ROF/CQB builds to take advantage of the form factor, not high FPS field builds where other rifles perform rather better.

I've experience with AEGs, I've built 3 M4s but never really touched on MP5s. I just love the way MP5 looks and the , also it's light weight. I'm tired of running around with 4.5 kg chungus all the time. With MP5 I don't care about ROF since my CQB area is restricted to semi-auto any ways. I just want maximum range and speed I can get from it with .36 BBs. I wanna know What is the maximum spring strength I can shove in there without breaking thegearbox shell, will do radiusing ofc and if there's any reinforced shells I'll opt for them. Big spring + full cylinder ? (maybe 80%) + .36bb what would be the optimal inner barrel length 360mm ? And as for battery size, don't those triangle handles fit big ol RC car batterys ? I prefer those over Airsoft branded ones since they offer more discharge rate and better price. Budget is no issue If it is possible to build a monster mp5 without opting for hpa I will build it.

 

[Swollen.D]

If MP5 Platform is bad what about HK53 ? Are they any different ?

 

[Doctor Jest]

Triangle handles. Erm.......WAIT....

This sort of thing?

https://www.davescustomairsoft.co.uk/fixed-stock-for-the-mp5-type-replicas

That would fit any batteries you want - a note about that: Super-high discharge rates can potentially cause issues in airsoft gearboxes and motors. Even if you re-wire throughout with 16 gauge silver wiring, and use top-of-the-line brushless motors for maximum torque the current draw on semi-auto is going to be enormous. Answering a question about spring power and gearbox shells is a little more straightforward....if you use a CNC V2 gearbox shell (Retroarms or similar) then I would say around M150 is the practical limit before you start reaching the point where you're placing insane stress on the gearbox.......with a full cylinder and .36g BB then perhaps yeah, a 6.03mm barrel at 380mm.

 

[Doctor Jest]

HK53 just substitutes bigger magazines and a different hop chamber.......which IMO is a big deal simply because you have more choices in which chamber to use and obviously, that provides a deal more stability and accuracy over an MP5 chamber. FWIW I am a MASSIVE H&K Fan so I absolutely appreciate your position......I did run an HK33 with the larger butt stock for years as a DMR without problems.

 

[Swollen.D]

Triangle handles. Erm.......WAIT....

This sort of thing?

https://www.davescustomairsoft.co.uk/fixed-stock-for-the-mp5-type-replicas

That would fit any batteries you want - a note about that: Super-high discharge rates can potentially cause issues in airsoft gearboxes and motors. Even if you re-wire throughout with 16 gauge silver wiring, and use top-of-the-line brushless motors for maximum torque the current draw on semi-auto is going to be enormous. Answering a question about spring power and gearbox shells is a little more straightforward....if you use a CNC V2 gearbox shell (Retroarms or similar) then I would say around M150 is the practical limit before you start reaching the point where you're placing insane stress on the gearbox.......with a full cylinder and .36g BB then perhaps yeah, a 6.03mm barrel at 380mm.

No that's a butstock, this here it should fit standard 2200Mah size RC lipo battery:

 

[Swollen.D]

HK53 just substitutes bigger magazines and a different hop chamber.......which IMO is a big deal simply because you have more choices in which chamber to use and obviously, that provides a deal more stability and accuracy over an MP5 chamber. FWIW I am a MASSIVE H&K Fan so I absolutely appreciate your position......I did run an HK33 with the larger butt stock for years as a DMR without problems.

HK33 is another great option! One with colapsable butstock especially. It is properly upgradeable ? Might want to max that instead of mp5 if it comes with more stability and upgrade options.

 

[Doctor Jest]

Oh, handguard. Right. It MIGHT fit 2200 mah, but it's probably a tight fit......potentially something that could be accomplished....I wouldn't want to hazard a guess without measuring it.

At the end of the day both the MP5 and HK33 are V2 gearboxes. They should, in theory, take any upgrades a V2 gearbox would normally accept but IMO it depends on how much of the original parts you want to retain and how much you want to spend.......if you go for a CNC gearbox and replace all the internals then either should be able to meet your requirements. The main difference is that the MP5 hop chamber doesn't offer the same degree of performance as the aftermarket parts which would fit the HK33.

Retroarms gearbox, Warhead motor, Siegetek gears, MAXX hop etc etc. It's the same list of parts you'd see anywhere IMO......

You want a snappy semi-auto with no FPS limits, correct?

 

[Swollen.D]

Correct, snappy semi and auto for fun. So you mentioned Maxx HopUp? Does that mean hk33 takes m4 upgrade parts ?

 

[Doctor Jest]

There will be parts that don't fit (which is true of every platform) but as far as I know then broadly speaking, Yes. I have seen an LCT HK33 with a Maxx in it........but google doesn't seem to provide many returns. I assume that means that as it is a less popular gun, fewer people are upgrading it and discovering its foibles. Mine was a Classic Army and I didn't experience any issues there........

 

[Swollen.D]

There will be parts that don't fit (which is true of every platform) but as far as I know then broadly speaking, Yes. I have seen an LCT HK33 with a Maxx in it........but google doesn't seem to provide many returns. I assume that means that as it is a less popular gun, fewer people are upgrading it and discovering its foibles. Mine was a Classic Army and I didn't experience any issues there........

What about G3A4 ? Looks exactly the same as HK33A3 but with a straight mag that looks miles better than curved one ? Are those 2 the same ? Are mags cross compatible or ?

 

[Doctor Jest]

No. The G3A4 is based on a 7.62mm round, the HK33A3 is 5.56mm.

Still has a V2 gearbox but a different hop chamber.

 

[Leo Greer]

Depends on how far you want the range to be out to. With some basic mods and few replacements I can make most guns hit 60. Above that it’s harder. For example I’m doing a build on an Arcturus NY06 CQB, which only has a 265mm barrel. The barrel was already good quality steel, and the hop unit was good, so all I did was replace the hop rubber with a PDI W-hold, and boom, 60 yards.

If I were you wanting to get 60 yards… get a variant with a standard or semi-standard V2 hop unit. If needed, replace with a G&G GR16 Rotary hop, which you can buy for $9 on Umbrella Armory right now. Use a basic fang style hop rubber like a Krytac, W-hold, or any of the others. They‘re easier to tune than other upgrade rubbers in my experience. Stabilize the barrel, etc, etc. Usual DMR mods.

I suggest you figure out the exact replica you want, and the range you’re trying to reach. You really don’t need insane power for a DMR, but if you’re asking for high FPS, we need to know how high exactly. 450 FPS (1.7j) is way different from 2.5j, 3j, etc.

I suggest staying away from the Maxx chamber. Pros: they work good. Cons: they only work good if you get it right, which can be really hard, some models don’t feed well at all, some models don’t work with certain mags, and they’re at least three times more expensive than a lot of other excellent options. Oh, and they’re picky about nozzle length.

Snappy semi isn’t too hard. ZCI HT and 13:1s. Even better, get whatever TPA you want from Chihai and do 13:1s. I’ve pulled up to M140 springs on 16 TPA/13:1, with very snappy semi. You’d probably want to use a torquier motor to avoid the motor heat issues I had with that build, but doing 22 or 24 TPA with 13:1 should pull a lot of springs.

On the flip side, I‘m working on a gun right now that will be using 18:1 gears and a 33K brushless. The brushless has so much torque that it acts like a 40K, and the trig response is insane. It’ll also pull absolutely whatever spring I want.

Gearbox shells are fun. It‘s hard to find one that fits your gun, aligns with your barrel group, and has the strength and compatibility to fit what you want.

 

[Swollen.D]

No. The G3A4 is based on a 7.62mm round, the HK33A3 is 5.56mm.

Still has a V2 gearbox but a different hop chamber.

Saw a reddit post, looks like Maxx hopup fits in G3 variants.

 

[Swollen.D]

Depends on how far you want the range to be out to. With some basic mods and few replacements I can make most guns hit 60. Above that it’s harder. For example I’m doing a build on an Arcturus NY06 CQB, which only has a 265mm barrel. The barrel was already good quality steel, and the hop unit was good, so all I did was replace the hop rubber with a PDI W-hold, and boom, 60 yards.

If I were you wanting to get 60 yards… get a variant with a standard or semi-standard V2 hop unit. If needed, replace with a G&G GR16 Rotary hop, which you can buy for $9 on Umbrella Armory right now. Use a basic fang style hop rubber like a Krytac, W-hold, or any of the others. They‘re easier to tune than other upgrade rubbers in my experience. Stabilize the barrel, etc, etc. Usual DMR mods.

I suggest you figure out the exact replica you want, and the range you’re trying to reach. You really don’t need insane power for a DMR, but if you’re asking for high FPS, we need to know how high exactly. 450 FPS (1.7j) is way different from 2.5j, 3j, etc.

I suggest staying away from the Maxx chamber. Pros: they work good. Cons: they only work good if you get it right, which can be really hard, some models don’t feed well at all, some models don’t work with certain mags, and they’re at least three times more expensive than a lot of other excellent options. Oh, and they’re picky about nozzle length.

Snappy semi isn’t too hard. ZCI HT and 13:1s. Even better, get whatever TPA you want from Chihai and do 13:1s. I’ve pulled up to M140 springs on 16 TPA/13:1, with very snappy semi. You’d probably want to use a torquier motor to avoid the motor heat issues I had with that build, but doing 22 or 24 TPA with 13:1 should pull a lot of springs.

On the flip side, I‘m working on a gun right now that will be using 18:1 gears and a 33K brushless. The brushless has so much torque that it acts like a 40K, and the trig response is insane. It’ll also pull absolutely whatever spring I want.

Gearbox shells are fun. It‘s hard to find one that fits your gun, aligns with your barrel group, and has the strength and compatibility to fit what you want.

What do you mean ? Are you saying that there are MP5s that are M4 HopUp compatible ? And as for build I'd summerize it as compact DMR, with ocassional full auto on top of it. Want a M170 or M180 spring in there, that's like over 600fps measured with .2s but I will be blasting .36bbs.

 

[SiliconeSword]

I'd not go on reddit for airsoft stuff, and I'd not get a MAXX.
I own the ME and like it, but you would be able to get the same or better performance from a G&G like mentioned already. To get that better performance, it's really just down to shimming the arm with tape or beer can, and maybe making my SS-nub or using something similar.

For power, it's up to your gearbox really, as some are stronger than others for various reasons. You'll want to use a small round file or dremel to round out the 90* corners on the front where you usually find cracks, and you'll want to use the longest and tightest inner barrel possible, keeping in mind to look at the 1TONNE AEG BARREL GUIDE to not go much over his recommended stuff. If you can, I'd lap the barrel, shim, center, and stabilize it, and then use a 2021 Maple Leaf bucking or an R-hop.

Can't speak on much else, I don't immerse myself in AEG stuff having been cleansed by the holy baths of HPA, and therefore have little experience to share.

 

[Doctor Jest]

I suggest staying away from the Maxx chamber. Pros: they work good. Cons: they only work good if you get it right, which can be really hard, some models don’t feed well at all, some models don’t work with certain mags, and they’re at least three times more expensive than a lot of other excellent options. Oh, and they’re picky about nozzle length.

This x one million.


I mentioned them as, inevitably, they get recommended as the "Best possible" unit when in truth, as you point out, they are absolute bastards a lot of the time due to the usual discrepancies in airsoft and manufacturing tolerances. It just seems like Swollen wants the "best of the best" so...........if building a G3-based rifle for CQB Then I would, 100% of the time go for either a G3SAS or an MC51. Owned both, run both in various configurations (sliding stock, fixed stock, external battery on a sling, battery in the stock) and they are superb options as alternatives to bloody M4s.

Gearbox shells are fun. It‘s hard to find one that fits your gun, aligns with your barrel group, and has the strength and compatibility to fit what you want.

Also this.

People don't seem to want to acknowledge that fitting airsoft parts and making a working AEG isn't as easy as picking out the most expensive/most recommended parts and throwing them together.There only has to be minor variations in sizing throughout and you have to subsequently spend hours fettling and filing to ensure everything matches up.

 

[Doctor Jest]

What do you mean ? Are you saying that there are MP5s that are M4 HopUp compatible ? And as for build I'd summerize it as compact DMR, with ocassional full auto on top of it. Want a M170 or M180 spring in there, that's like over 600fps measured with .2s but I will be blasting .36bbs.

No. The MP5 has a different hop chamber due to the fact that it's based on a 9 mm-sized magazine.......here's the truth:

Running that sort of ridiculous spring puts stress on ANY build. We linked you to that thread of Cripplegunner's with his insane DMR and whilst you aren't aiming for the 5j he achieved, you're still talking about 3.4j so you need to realise that whilst possible to assemble, the internal stress is significant to the point of compromising reliability and a .36 will be clocking 447 fps - which could significantly affect downrange accuracy and consistency as we talked about in your other thread.

TL;DR With diminishing returns and stress, that sort of FPS isn't really worth it.