ROF

[Barlow]

Okay guys so at the moment my G&P Sentry is doing around 24rps completely stock with a 9.6 battery, however, tomorrow I'm going to have my gun serviced with a few upgrades done to the gearbox. One of the upgrades is a more powerful spring. At the moment my rifle is firing about 280 fps and it's being upgraded to shoot around 328 (I do CQB mainly). The question I'm most interested in is how much will a more powerful spring bring down my rate of fire? Other upgrades include a reshimming, new o-ring, sorbo pad installed to reduce shock transfer to the gearbox, piston rails and tappet plate polished to reduce drag as well as some other gearbox maintenance.

Thanks guys!

[North West Outpost]

Re: ROF

Just get them to fit a decent torque motor and jobs a goodun!

I assume the sorbo is for AOE in which case you can use a smallish 11.1 LiPo to take up any slowing if you need to.

[Barlow]

Re: ROF

Thanks for the reply mate. Well I've been looking at going the lipo route basically because they are better more efficient batteries and the fact that I'm considering a new stock so any new battery will have to go in the stock tube. Another issue that I have noticed is that when I'm pulling the trigger, I have to squeeze it back very far whereas it used to be quite a light pull for the weapon to fire. Any clues what might be causing this?

[laurence]

Re: ROF

I think its your trigger block, basically you have a bar which pushes into to bars connecting a circuit bit like the U pushing down into a | |.

Sorry for the terrible 'demonstration' or whatever but think of it as the U pushing into the | | completing the circuit, over time these could have been pushed apart and so you have to squeeze more for them to make contact. You just need to squeeze them together a bit.

[Barlow]

Re: ROF

Will have a look at that as well, I understand what you are on about, cheers man.

[TK8456]

Re: ROF

I'd say you probably want to upgrade your battery then?
If you're adding more work to what the motor needs to do then it'll ask for more current to do it. However you maybe fine as you are but it'll drain faster than you're used to...?

Basic maths here but this equation is a beauty:

Power = Volts x Amps
(turning power/torque of your motor = Battery Volts x Battery mAh)

May also be worth googling Lenz' Law and back EMF
When doing so cast your mind back to little scaletric cars and turning the back tyre as a kid.
It's hard, yes? Lenz Law is the reason. Motors don't want to change speed, they need a push to do and that comes from the current it'll ask for.

[baddbaz]

Re: ROF

Going lipo will give you better trigger response and longer run times it's just a case of finding the biggest capacity battery you can to fit in the gun . 11.1 will increase the response yet again. But make sure the g/ box is up to the job before you go for any high ampage ones .. Ie 15 c and above as they will accelerate wear and find any weak spots in the box . Also invest in a good charger and you will never go back to nimh batteries again .. Also deans or the newer equivalent ones will carry a fraction more ampage/ current than the Tamiya connectors .

[North West Outpost]

Re: ROF

Going lipo will give you better trigger response and longer run times it's just a case of finding the biggest capacity battery you can to fit in the gun . 11.1 will increase the response yet again. But make sure the g/ box is up to the job before you go for any high ampage ones .. Ie 15 c and above as they will accelerate wear and find any weak spots in the box . Also invest in a good charger and you will never go back to nimh batteries again .. Also deans or the newer equivalent ones will carry a fraction more ampage/ current than the Tamiya connectors .

I think I am about 10 steps ahead of you there... If it's being sorbo'd it will be for AOE correction and so long as you have circa an M100 it will be fine. The tech will reshim when stripping the gear box checking the other parts. Well I used to.

[Longshot]

Re: ROF

I think you need to come back to techy work and sort Barlow's gun for him Midas - you did a great job on my Sentry!

[Barlow]

Re: ROF

Just an update on this guys, had the work done and the rof only came down by 1rps and the fps has gone up by about 50-60 so not too shabby. Turns out I have a short stroked piston, gears as well as a m120 high speed motor so it was able to handle the increased fps with no drama!

[Kaladyr]

Re: ROF

Trigger pull fixed too?
If it's been used for some time and you've not got a mosfet on then you may even find the trigger contacts are burning away, a mosfet in there before you go lipo is well worthwhile