Energy Reinforced 8mm Gearbox Set with Quick Spring Change

[Conker]

Hi all,

I'm building one AEG with two configurations: 1 for outdoor games (target: 390-395 fps) and one for CQB (target: 340-345fps).

As it's not an ICS, obviously it's timewasting to change the spring for each game. So I've looked around, and found the Energy Reinforced 8mm Gearbox Set with Quick Spring Change (see AirsoftGlobal) to ease the process. I figured that at this price, it's worth a try.

My current gearbox has the stock, 6mm bushings shell.

What I don't like, however, is that it's a 8mm gearbox. To my knowledge, there isn't any 8mm bushings and nobody ever recommended me the use of bearings for that purpose.

Questions:
-Does anybody have experience with those gearboxes?
-What do you think of the bearings issue? Is that something big, in your opinion and experience?

Thanks!
Conker

[The Saint]

8mm bearing is generally regarded as very reliable at 400fps, since 8mm bearings are designed to support safe 400fps+ operation.

Based on how that design looks, you'll still have to pop the mechbox out of the lower receiver to change the spring. I'd considering getting an ICS or an ARES if power adjustment is that big an issue.

[m102404]

http://www.airsoftparts.ca/store2/in...oducts_id=1411

Also, you might want to consider a setup like this:
- CQBR outer barrel, CQB inner...set to 340-ish
- CQBR outer barrel, silencer, M4A1 (or touch longer sig length) tightbore...might shoot 380-ish with the same mechbox.
- same upper, lower, mechbox, motor, etc...

Setup each inner barrel on it's own hopup unit.

Takes just a minute to switch configs...indoor FPS short gun, outdoor usable longer gun. Same grip, rails, sights, etc... Over the past year or so I've setup about a half dozen M4's that way.

You didn't specify which model rifle you're shooting...so it's a bit hard to discuss different setup options.

Tys

[Conker]

Originally Posted by The Saint

Based on how that design looks, you'll still have to pop the mechbox out of the lower receiver to change the spring.

In my particular case, there's no issue. I just checked and it's only removing two body pins, nothing more.

As for the bearings vs bushings, now knowing that both exist (thanks m102404), what is your opinion on this? Considering I'm not a trigger happy guy, so the goal is not extreme ROF nor extreme FPS, but I'm more looking for a crisp trigger response.

[m102404]

Bushings if possible. But I've run 8mm bearings on several rigs with no issues.

Tys

[lemegacool]

Originally Posted by Conker

As for the bearings vs bushings, now knowing that both exist (thanks m102404), what is your opinion on this? Considering I'm not a trigger happy guy, so the goal is not extreme ROF nor extreme FPS, but I'm more looking for a crisp trigger response.

i'm no tys but i'll give my opinion...

bushing are preferable but lately i've been exerimenting with bearings on the bevel gear only (the one that gets less stress) makes the gears spins a bit more freely...

as for the fps thing... remember the fields limits are limits not goals... for indoor i recommend 300-315 fps setup (the guy you shot at 20 feet will be less angry at you ...lol) and for outdoor the best seems to be around 360-380 fps... but again i gamed a 310 fps gun outside and got GREAT results... that same day a friend was gaming my 280 fps ak and he got like 30 kills lol
just remeber to shoot the heaviest bbs your fps/hop up rubber allows you!

[Conker]

At one point I was able to get some kills with my HK416 which read 180fps with.20, and I was playing with .28... well, not a lot of kills, but still doable.

Outdoors, I prefer to be the closest possible to the 400fps mark as it's going to be more of a DMR-style setup, so range is a must (sure, tightbore, compression checks and new rubber are also on the list).

Indoors, ~340fps would be good, but you're right that it's not necessarily a goal.

But I'm still unsure of bushings vs bearings, lol.

[delta76]

Originally Posted by m102404

http://www.airsoftparts.ca/store2/in...oducts_id=1411

Also, you might want to consider a setup like this:
- CQBR outer barrel, CQB inner...set to 340-ish
- CQBR outer barrel, silencer, M4A1 (or touch longer sig length) tightbore...might shoot 380-ish with the same mechbox.
- same upper, lower, mechbox, motor, etc...

Setup each inner barrel on it's own hopup unit.

Takes just a minute to switch configs...indoor FPS short gun, outdoor usable longer gun. Same grip, rails, sights, etc... Over the past year or so I've setup about a half dozen M4's that way.

You didn't specify which model rifle you're shooting...so it's a bit hard to discuss different setup options.

Tys

Any concern about cylinder porting with this setup?? Would this idea work with a 300mm barrel for CQB and a 363mm barrel for field use? Would the shorter barrel be standard 6.08?

[theguy]

Don't both 300 and 363 inners work with type 1 ported cylinders?

[delta76]

Originally Posted by theguy

Don't both 300 and 363 inners work with type 1 ported cylinders?

That's why I was asking; this way you wouldn't need to worry about cylinder porting, but the issue would be whether you'd see a significant variance in fps (i.e. 340fps on the 300mm and 360-380fps on the 363mm) Not sure what inner barrel lengths Tyson was referring to in order to achieve that setup.

[m102404]

280mm-ish and 363mm-ish...give or take a bit...I think, it was a while ago. I think the CQBR barrel was custom cut to fit and the inner might have been a 390-ish barrel. If I recall correctly the CQB barrel might have been cut back a half inch...and the "long" barrels were a bit longer than a TM M4A1.

I think the cylinders were M4 ported...I think half the setups had Systema silent head setups.

Either way, it was the inner barrel length that made the FPS difference. Sure there's some theoretical differences between mounting each on a different hopup unit, with their own hopup rubber...but the hopup units were the same and so were the rubbers. So for all intents and purposes the only difference was the barrel length.

If you want to test it out, buy a brass M4A1 barrel and cut off 1" at a time. You need to recrown/clean the barrel each time, but it doesn't take long.

Got to pack it in for the night...have fun guys.

Tys

[Styrak]

Originally Posted by delta76

Any concern about cylinder porting with this setup?? Would this idea work with a 300mm barrel for CQB and a 363mm barrel for field use? Would the shorter barrel be standard 6.08?

Cylinder porting isn't an issue, your FPS will just drop with the shorter barrel.

I used to run two setups for my AUG, one with a PSG-length (590mm) inner and one CQB with a M4 length (363mm) inner. FPS dropped by about 80 switching to the shorter barrel, with a non-ported cylinder (never changed it).