HS SSG build advice

[The_Jelly]

Hey guys!

So I managed to get a G&g shell and some parts for next to nothing and have decided to do an SSG build with 13:1 ratio gears.

I have scoured the internet but there has been so many contradictory things said So I am looking for some advice on what to except and what to look out for. 

Heres my build list:

G&G gearbox shell
G&G ETU (they're crap I know but it's in the box)
SHS steel bushings
SHS 15t blue piston
Stock g&g cylinder or airsoft pros cylinder
SHS 13:1 gear set
Maxx double oring cylinder head
Maxx oring air nozzle
Maxx bearing spring guide
SHS tappet plate
G&G ifrit neo 25k motor or ASG boost neo 30k motor 
M120 spring or guarder sp120(which is like an m130) 

Now my aim is to have roughly 350FPS to 380FPS and +-30RPS 

This is the first time I will be attempting a high speed build and I have read a few guides. 

I intend on Swiss cheesing the piston

Correcting AOE

Possibly installing a sector delay chip

And if I can avoid it NOT short stroking the sector. 

My question to you is would this build suffer from PME? And if so would you recommend I use the stronger m130 spring and short stroke? 

I look forward to your input 

 

[Asomodai]

If you are not short stroking the sector, how are you going to bring the FPS down with that M120 spring?

 

[Prisce]

I don’t think some of those parts are compatible with each other.

It’s a similar build to my custom, you don’t need a M120, my M100 is kicking out 348fps give or take 2, and I’m over 30RPS with The Titan set up correctly.  I have reduced the RPS as I’m not a sadist.

 

[The_Jelly]

@AsomodaiSorry for the late reply. My local fields are 400FPS limits, so long as I'm under that I'll be fine. The reason for choosing an m120 was so that I could avoid PME. People have told me that on 13:1 gears and a 16-18TPA motor I should get around 35RPS and be at the cusp of PME so I have been advised to use a stronger spring and if FPS is high short stroke. 

Alternatively I'll use an m100/m110 spring that should keep me below 400FPS if I don't need to short stroke the gear set id be happy. 

@Prisce please let me know what parts you are referring too, and I'll be sure to review them and change them out if need be.

I'm from South Africa so parts availability is extremely low and I have been hustling to arrange what i'v got. 

Can you please eloborate on your build a little more as I think it will assit me in understanding this high speed build a little better. 

What ratio gears are u running? I'd be happy at said FPS and RPS as explained above I'm looking for around 30RPS With a snappy trigger. 

 

[Asomodai]

@AsomodaiSorry for the late reply. My local fields are 400FPS limits, so long as I'm under that I'll be fine. The reason for choosing an m120 was so that I could avoid PME. People have told me that on 13:1 gears and a 16-18TPA motor I should get around 35RPS and be at the cusp of PME so I have been advised to use a stronger spring and if FPS is high short stroke. 

Alternatively I'll use an m100/m110 spring that should keep me below 400FPS if I don't need to short stroke the gear set id be happy. 

@Prisce please let me know what parts you are referring too, and I'll be sure to review them and change them out if need be.

I'm from South Africa so parts availability is extremely low and I have been hustling to arrange what i'v got. 

Can you please eloborate on your build a little more as I think it will assit me in understanding this high speed build a little better. 

What ratio gears are u running? I'd be happy at said FPS and RPS as explained above I'm looking for around 30RPS With a snappy trigger. 

M120 would give you at least 420FPS even with terrible compression. 450 with decent compression. You need to short stroke the sector full stop to get the RPS you want at a safe FPS and avoid PME.

 

[The_Jelly]

M120 would give you at least 420FPS even with terrible compression. 450 with decent compression. You need to short stroke the sector full stop to get the RPS you want at a safe FPS and avoid PME.

I very much appreciate your input! Thank you so much! I forgot to also mention the build will go into an ARP556 with a barrel length of 130mm if I'm not mistaken so FPS may be a little lower Than what you have quoted but non the less I understand what is required. 

In your opinion, should I put the build together, chrono the gun see what FPS I'm getting. Then decide how many teeth to short stroke by based on what FPS was measured? 

And i'v read some where that ita roughly 10-12FPS per tooth reduction is this accurate? 

 

[Prisce]

@AsomodaiSorry for the late reply. My local fields are 400FPS limits, so long as I'm under that I'll be fine. The reason for choosing an m120 was so that I could avoid PME. People have told me that on 13:1 gears and a 16-18TPA motor I should get around 35RPS and be at the cusp of PME so I have been advised to use a stronger spring and if FPS is high short stroke. 

Alternatively I'll use an m100/m110 spring that should keep me below 400FPS if I don't need to short stroke the gear set id be happy. 

@Prisce please let me know what parts you are referring too, and I'll be sure to review them and change them out if need be.

I'm from South Africa so parts availability is extremely low and I have been hustling to arrange what i'v got. 

Can you please eloborate on your build a little more as I think it will assit me in understanding this high speed build a little better. 

What ratio gears are u running? I'd be happy at said FPS and RPS as explained above I'm looking for around 30RPS With a snappy trigger. 

My build used: 

Lonex Shell

ASG Ultimate Bushings

SHS 13:1 Gearset

SHS cylinder head and Nozzle

ICS Pom Piston and head

M100 Modify Spring

SHS ball bearing spring guide

ASG 40k motor

Lonex Tappet plate and selector  

Gate Titan mosfet

Had almost perfect AoE, corrected shimming with very few shims. 

I’m shooting 348fps give or take 2,  very consistent, extremely accurate if I aim it in the right direction. Getting between 30-35rps , depending on how I set the Titan and the battery is an 11.1V. I’m getting 50M with a G&g green standard nub in a pro win hop unit, I have a prommy purple to put in it when I get a minute.

Very happy with it so far, always room for improvement, but I currently don’t need it!

 

[The_Jelly]

My build used: 

Lonex Shell

ASG Ultimate Bushings

SHS 13:1 Gearset

SHS cylinder head and Nozzle

ICS Pom Piston and head

M100 Modify Spring

SHS ball bearing spring guide

ASG 40k motor

Lonex Tappet plate and selector  

Gate Titan mosfet

Had almost perfect AoE, corrected shimming with very few shims. 

I’m shooting 348fps give or take 2,  very consistent, extremely accurate if I aim it in the right direction. Getting between 30-35rps , depending on how I set the Titan and the battery is an 11.1V. I’m getting 50M with a G&g green standard nub in a pro win hop unit, I have a prommy purple to put in it when I get a minute.

Very happy with it so far, always room for improvement, but I currently don’t need it!

This is awesome information! Thank you so much for sharing this! So jealous! Wish we could get gate's here!

Those g&g green buckings are so good. I thought it did better than the prommy purple I used to have. I'm now using maple leaf blue 70D bucking and omega nub. Very happy with the set up as well. 

It's a very nice build! But I am somewhat confused! 

An m100 coupled with a 40k motor and 13:1 ratio gears, wouldn't that be PME central?

Sorry for all the questions regarding PME Iv just read so many contradictory threads and write ups on the matter. 

 

[Prisce]

This is awesome information! Thank you so much for sharing this! So jealous! Wish we could get gate's here!

Those g&g green buckings are so good. I thought it did better than the prommy purple I used to have. I'm now using maple leaf blue 70D bucking and omega nub. Very happy with the set up as well. 

It's a very nice build! But I am somewhat confused! 

An m100 coupled with a 40k motor and 13:1 ratio gears, wouldn't that be PME central?

Sorry for all the questions regarding PME Iv just read so many contradictory threads and write ups on the matter. 

I thought I would get no end of issues. But because of the Titan, and making sure AoE is set correctly I have no issues at all. You probably can get a titan over there, have you thought about asking retailers in the UK if they’d ship to you. Pretty sure FireSupport will.

 

[The_Jelly]

I'm sure I could get one in definetly but it's the price that goes crazy.  Currently 1 pound translates to R18.23 South African Rands. So the bad exchange, coupled with import duties and shipping make it exorbitant. The cheapest way is to get it via US or asia when someone visits. But that's like once in a blue moon. However there are some Perun etu's coming to a retailer locally at the end of this week which I am interested in. 

Im amazed that your gun is cycling fine on that spring and motor I won't lie. Awesome build though! I'm just waiting for my cylinder head and nozzle to arrive and I'll get straight to the to the building. So stay posted I'll have some updates and a ton of questions and keen to get this done with your guys help! 

 

[The_Jelly]

Hi guys! So it took alot longer to get the parts I required to finish this build and some parts have changed. I have put the build together but am experiencing issues. I'll list my current parts and explain what I'm facing and hope you guys can point me in the right direction! 

My build is as follows:

G&G box 

G&G selector 

G&G m120 spring

G&G IFRIT 25K motor

SHS 13:1 gears (2teeth short stroked) 

SHS 15t piston (Swiss cheese'd bearing removed) 

SHS tappet plate

SHS steel bushes

Maxx v2 bearing spring guide

Maxx Trigger

Perun optical etu

Airsoft pros type0 cylinder

Double oring cylinder head (Teflon taped) 

Oring nozzle

Now i'v taken it apart and put it back together a couple times but I'm getting around 260FPS and 29RPS. The only thing I can think of is it's tappet timing or a bad seal between the nozzle and hop up causing the low FPS. Or being over volumed so the BB is leaving the barrel before maximum velocity is reached. I have tried a sector delay chip on and off and it hasn't made much difference. I have also tried a 270mm barrel instead of the 130mm stock barrel and didn't see much of an increase yet again. 

What do you think I have done wrong? 

 

[Davegolf]

Hi!

Over volume won't be killing FPS.

Check your airseals, start from the top;

- Piston head to cylinder

- Cylinder head to cylinder

- Nozzle to cylinder head

These need to be sound if you want any consistency.

Next check your bucking is properly seated.

Now check your nozzle to bucking air seal.

The gearbox should be at rest (piston and tappet plate/nozzle forwards).

With the hop unit pushed into the gearbox (out of the gun) you should be able to blow in the barrel and experience zero air loss.

You need to be 100% sure all your parts are working together for perfect air seal.

Heres the killer though, M120, 120mm barrel, SS 2 teeth is not going to make much punch.

Id be surprised if you get 300 FPS from it.

Youre losing a LOT of power with a sub 200mm barrel and youre losing 10-15 FPS per tooth.

My MP5 PDW;

SP120 spring

BB Spring guide

150mm barrel

Type 2 cylinder

SS 1 tooth

= 300 FPS 

That type 0 cylinder won't help with piston speed either, you should run a type 2.

Thatll still over volume a 120mm barrel.

 

[The_Jelly]

Hi!

Over volume won't be killing FPS.

Check your airseals, start from the top;

- Piston head to cylinder

- Cylinder head to cylinder

- Nozzle to cylinder head

These need to be sound if you want any consistency.

Next check your bucking is properly seated.

Now check your nozzle to bucking air seal.

The gearbox should be at rest (piston and tappet plate/nozzle forwards).

With the hop unit pushed into the gearbox (out of the gun) you should be able to blow in the barrel and experience zero air loss.

You need to be 100% sure all your parts are working together for perfect air seal.

Heres the killer though, M120, 120mm barrel, SS 2 teeth is not going to make much punch.

Id be surprised if you get 300 FPS from it.

Youre losing a LOT of power with a sub 200mm barrel and youre losing 10-15 FPS per tooth.

My MP5 PDW;

SP120 spring

BB Spring guide

150mm barrel

Type 2 cylinder

SS 1 tooth

= 300 FPS 

That type 0 cylinder won't help with piston speed either, you should run a type 2.

Thatll still over volume a 120mm barrel.

@Davegolf thank you so much for your informative response!

I opened the box up tonight and went thought it as you explained. 

1. I picked up a small airleak when testing the compression between piston to cylinder that I wasn't happy about. I changed the G&G piston head out for another that allowed the oring to spin more freely and this gave me a near perfect compression. I also swopped out the type0 cylinder for a type 2 as per your suggestion. 

2. I tested the airseal between the hopup and the nozzle using two seperate barrel/hopup combos. I found that there was a massive airleak here. You were spot on! I wasn't sure how to tackle this as I didn't have other size Nozzles. But I decided to take the nozzle out the gun, place it in the back of the hopup and blow through it whilst blocking the rear of the nozzle. I had a perfect seal. So I figured I may have an issue where the nozzle is not moving far enough into the hop up unit. 

3. I had a used tappet plate lying around that I decided to use as an experiment. I sanded the front of the tappet plate down hoping this would allow the nozzle to enter the hopup unit ever so slightly more. I tested the compression once again as you explained and achieved a seal. I assembled the receiver and blew down the barrel once again and it was still solid. I took one shot and the blew down the barrel again and had no airseal again. Seems I have overspin so the nozzle was cocked in a slight back postion. 

4. Now the gun won't feed since I changed the tappet plate which had a slightly different fin pattern. I had taken the delay chip out and thought this was the issue, so I re opened the box and installed the delayer chip but once again had the same problem gun won't feed. 

I have run out of time, so I will open the box up tomorrow night after work.

I am thinking I'll put the SHS tappet plate back in, as the gun was feeding fine with this tappet installed. What do you suggest I do about the nozzle leak and overspin issue? 

If u suggest I buy a longer air nozzle I can do so, but just fear running into feeding issues once again. 

With the overspin I can try enable AB on the perun fet to assit? 

Lastly regarding your comment on the barrel length, 300fps is low I might have short stroked a tooth too much but I was doing my best to avoid PME. Should I have taken one tooth of instead? And would this have been enough to avoid PME but aid my FPS?

And if I were to to only achieve +-300FPS would you suggest I up the spring to an m130 to hopefully put me around 340FPS? I know this would affect RPS a little. But I do have an ASG boost 30k 16TPA motor that I can make available to counter the loss. 

Sorry for the wall of text! Let me know your thoughts? 

 

[Davegolf]

Hi, at least you are making forward progress and 'putting things to bed'.

With a high ROF youll def want the delayer chip in.

If the nozzle is too long/tappet does not go back far enough you wont feed.

Vice versa for air seal, you need a long enough nozzle, and enough forward travel.

Also worth noting that different bucking and nozzle combos can have a dramatic effect on air seal.

Its all a balancing act, takes time, trial and error to get the correct parts that work well together.

At sub 35 RPS with a hefty spring PME should not be an issue.

A stronger spring will also counter some over spin.

Active braking may well be required, but use as little as possible.

Just for reference it is normal for an AEG to rest with the nozzle slightly retracted, so you can only do the bucking to nozzle test by resetting the gearbox one way or the other.

 

[The_Jelly]

Okay another update,

I decided to try the stock tappet plate from another one of my G&G gun and i built it back up.

My FPS jumped to 365FPS with a 4-5FPS variance between shots.

I compared the two tappets and noticed the  the SHS fin was much wider and wasn't allowing the tappet to fully move forward.

So it was the tappet plate all along. The 365 FPS chrono was done using  a 285mm 6.03 Prommy barrel.

I put the stock barrel in and got 300FPS on the dot.

I am wanting to put a slightly extended TBB in so I sit around the 320-340FPS mark so might extended it to between 175mm-190mm depending on the length of my suppressor.

Thank you so much for your help! you have been pretty spot on!

 

[Davegolf]

Excellent, you know it's all good if at 300 with the short barrel, nice job.

Whats you build spec in the end?

 

[The_Jelly]

@Davegolf Apologies for the delayed reply, been a busy few days!

Okay I have another update, so although I managed to get the gun firing at the above stated FPS, when I did the RPS chrono guess what? it gave me a reading of 27.2RPS and then I heard a horrible noise

Stripped the box down immediately and all teeth on the bevel gear had been sheared off. I inspected the teeth on the piston and saw that there was a little wear on the piston teeth indicating PME and the weakest point was probably the bevel.

I checked the damaged bevel gear against a standard G&G bevel and it had the same amount of teeth.

So I re-shimmed the gun with the new bevel and decided to install an m130 spring to assist with the piston returning quicker on its stroke to aid in combating the PME.

I am now shooting 330FPS with original ARP barrel(130mm) and 390FPS with a Prommy 285mm 6.03 TB barrel.

However my RPS has obviously dropped due to the heavier spring and I am now at 25.3RPS.

I'm pretty bleak at the results seeing that with a stock ARP with the prommy barrel listed above I get between 380FPS-400FPS and approximately 22-23RPS on an m120 and 18:1 gears.

The goal for this build was +-350FPS and approximately 30RPS as i wanted a speed build) Now I can live with a lower FPS but I definitely would like to be closer to 30RPS.

So what options do I have left now?

1. Change the stock G&G IFRIT 25K 18TPA motor to the ASG Boost 30k 16TPA I have in another gun? (whilst keeping the m130 spring)

2. Short stroke the sector gear another tooth and loose some more FPS but gain slight RPS? (whilst keeping the m130 spring)

3. Do both of the above? and if so are there any concerns regarding PME, Overpsin, tappet timing etc.

I'm hoping you can point me in the right direction

The final specs are as follows:

G&G box

G&G original tappet plate(SHS tappet in the photo was replaced with the G&G one) 

G&G selector plate

G&G piston head

Perun optical ETU

SHS 13:1 Gears (short stroked 2 teeth) 

SHS m130 spring (spring in the photo was a stock G&G m120)

SHS 15t Piston Swiss cheese'd

G&G type 2 cylinder (type 0 cylinder in photo replaced with G&G one)

Generic air nozzle

Maxx v2 bearing spring guide

Maxx flat trigger

 

[Davegolf]

Why are you so hung up on the FPS?

Youre always going to be fighting a perpetual battle, speed vs power with a short ass barrel.

Thats what HPA is for ?

My little MP5PDW as said is 300fps, but Rhop'd shoots 50M accurate.

If your into silencers extend the barrel into that??

 

[The_Jelly]

Why are you so hung up on the FPS?

Youre always going to be fighting a perpetual battle, speed vs power with a short ass barrel.

Thats what HPA is for ?

My little MP5PDW as said is 300fps, but Rhop'd shoots 50M accurate.

If your into silencers extend the barrel into that??

As I said I dropped the m130 in because of the PME that stripped my bevel gear. I also stated I dont mind loosing FPS to get my speed up as I was bleak at getting 25RPS due to the m130. So my question is more aimed at getting my RPS closer to 30 and if it means a loss in FPS I'm happy with that.  So I'm going to try the ASG boost motor this weekend, and see what RPS I get. If I'm still not happy do I remove a tooth on the sector to aid? 

 

[Davegolf]

If you haven't already you normally remove the same number of teeth from the sector as the piston.