Gearbox/spring/motor question

[conky44]

Hi guys,

I have a m4 with a g&p highspeed ratio gearbox (30 or so bps). I have a soft spring that needs to be replaced, I am only getting 270fps with .25bb. I have installed a new madbull 6.03 but have not crono it as of yet. Also I have a g&p m120 motor, I have the following questions:

1. What is max spring this setup with m120 motor could pull, without losing tons of ROF.
2. Would a new motor, keep the speed and allow for a high spring, ie sp120 or something if this m120 motor would not.
3. If a new motor is required, what would be the best one for ROF and a spring in the sp120 range. Ie M160, M180 satan, Systema, J&P.

Looking to go to around 350 or so fps, I have ordered a Sp120 Guarder spring.



Thanks,

Conky!

[kiru]

The point of having a high rate of fire isn't for you to hit hard. And if you are shooting at 270fps with 0.25 bbs you are probably using a m100 or equivalent spring which normally shoots about 300-320 fps with 0.2 bbs.

As for the g&p m120 motor from my knowledge is built for high speed (increased rof) and shouldnt be used with heavier springs over m110 or equivalent, otherwise you'll be stressing it big time. If you want to shoot with a m120 spring (380-400 fps with 0.2) or above you may want to consider using a high torque motor such as g&p m140 with high torque gear sets. As heavier springs will put more stress on your gears and wear them out faster if not meant for torque. Though you will of course lose some rof in the process. And your gear set is made for higher rate of fire and is not meant for pulling heavier springs like a m120. You can but you will be stripping those gears alot faster.

So if you want to shoot 350fps with 0.25s you may want to consider losing some rof and going high torque. Otherwise a m110 spring or equivalent would be sufficient enough for you and should work just fine with your current set up without making much change.

[conky44]

What make of spring would you recommend?

Thanks,

Conky!

[Szevin]

Slinky.

[kiru]

Prometheus, guarder, PDI, Madbull springs from my experience are pretty good springs.

[conky44]

I have a SP110 Guarder on order, will that be ok. I will also look into the madbulls.

[kiru]

Yes guarders make pretty decent springs so you will be fine. Just to add, with a 110 spring you won't be shooting 350fps with 0.25, you'll probably be shooting a consistent 310-320 fps with 0.25 and 340-360 with 0.20. Just in case you misunderstood me.

[L473ncy]

Also Modify springs but their naming scheme is a bit messed up.

S80 (SP80) should be a 1Joule spring (~328 FPS on .20)
But the S90 people are saying also gets 330 FPS.....
The S100 is supposedly around 360 (which would put it close to a "typical" M100)
S110 is 360-380

If you ask me I would probably aim for around 350 using .20's or around 310 on .25's.

Also remember that running a high speed setup leads to premature parts failure because of simple stresses placed on the internals (especially on high power springs). The best would be to use a 1 Joule spring but if you're looking for a bit more oomph and faster barrel to target time I would toss in something like an M110 aiming for around 340-350 FPS. Also I would make sure the compression parts have a perfect seal or you could be losing power and need a higher power spring to reach the target FPS.

[conky44]

Thanks guys,

So I will put in the sp110 as this should not put stress on the gear box, and give me a 310-320fps correct. Also I have ordered a new air nozzel to be on the safe side.

conky

[Szevin]

Wow, I just installed a modify s110. I really didn't think it would shoot that hard... I was aiming for 350... Whoops! Good to know though!

[panzergrenadier]

Originally Posted by kiru

As for the g&p m120 motor from my knowledge is built for high speed (increased rof) and shouldnt be used with heavier springs over m110 or equivalent, otherwise you'll be stressing it big time.

The M120 Motor is meant to be used with an M120 Gearbox... which has a 120 Spring in it. (380-400fps)

[ThunderCactus]

If you want high ROF without a crazy setup, you should probably stick to 350fps and under.
Prometheus rates high speed gear sets to run under 350fps.

[kiru]

Originally Posted by panzergrenadier

The M120 Motor is meant to be used with an M120 Gearbox... which has a 120 Spring in it. (380-400fps)

Sure the motor can pull it (I didn't say it can't but just shouldn't referring to the spec of his gun provided), and he did state he is using a high speed ratio gearset therefore a heavier spring will just stress the gearbox and increasing the wear on them overall.

[conky44]

Thanks for all the help.

Now with the postal strike, who knows when I'll get the spring!
If that one does not work out ill got to a different spring and possible motor setup. I dont want to lose 30 balls a second! lol

Conky

[THe_Silencer]

Originally Posted by kiru

Prometheus, guarder, PDI, Madbull springs from my experience are pretty good springs.

I wouldn't recommend PDI springs. Their labeling is inaccurate and their springs lose their stiffness fast.