Precocking

[Sewdhull]

Does precocking give fastest trigger response, can you get close without?

Is it noticeable in a game?

 

[Colin Allen]

Yes it does and yes it is.

There are other ways of achieving faster trigger response, such as fitting an FCU that includes trigger sensitivity adjustment.

 

[Pseudotectonic]

yes

 

[Adolf Hamster]

yes

^

This

There's really one downside to precocking, which is making the motor cold start with almost maximum load on it, which a weaker motor may not be able to do.

But if you care enough to be messing around with precocking then you either have, or dont mind getting a decent motor.

The other issue is leaving a gun in a precocked state might depending on the quality of the mainspring see a drop in energy during storage, although there are some methods around this:

1. Some guns have a de-cocking mechanism, although they're more the exception rather than the norm

2. Some mosfets have a de-cocking feature (eg hold trigger in semi for a few seconds and it'll cycle to remove the precock)

3. Other guns you *can* manually push the piston rearwards with a flat-ended tool through the nozzle to de-cock it.

4. Some gearboxes have a slot that enables you to manually disengage the anti reversal latch

Otherwise it's all the "trigger response" from a higher speed build, without the downsides of said higher speed build.

You can get snappy guns without it, thats what all the short stroking/high speed gears/speediboi motors/chunky batteries etc are aimed at, but its so much easier to slap a precocking mosfet on a more moderate build and enjoy your gun not eating itself every other game.

 

[Sewdhull]

Thanks, I'm not after high rates of fire, but do like snappy semi.

With the right gears and motor etc I can get decent semi but it seems like I may have to get a posh etu.

I did wonder if id really notice given that were talking milliseconds...

 

[Leo Greer]

My primary:

Arcturus NY06

Stock gears, wiring harness, microswitch trigger, inline MOSFET, deans plug.

T238 brushless motor.

You can get great trigger response with just a motor, 11.1v (amperage is irrelevant as long as the motor has enough current), and good tuning. You have less spam capability than a build with an ETU because of the microswitch trigger, but the actual trigger response is just as good.

 

[Pseudotectonic]

@Leo Greer From my measurement that is about 39 ms trigger response

The best I have seen in all of the internets is a 19 ms setup with a 28 TPA and m130 spring, unknown gear ratio (could be even 18:1) but that guy had somehow gotten a precocking that is literally the piston just sitting on the very last teeth before release, and the sound is just like a spring rifle because it really sounds instantaneous, sadly the vid was deleted and I could only dig out my reddit PMs for the numbers, but that was the theoretical peak of trigger response and I am so glad to have witnessed it, and it was better than every single youtube video or clips of people showing their trigger response, so that is the ceiling to aim for if there is one

 

[Impulse]

There is also more stress on the parts with pre-cocking, so you'll likely need to do maintenance and potentially replace parts more often.  It's not a massive thing and it's not like your gears and piston will be exploding every other game, but over time there will be increased wear on the gearbox parts.

 

[Colin Allen]

Thanks, I'm not after high rates of fire, but do like snappy semi.

With the right gears and motor etc I can get decent semi but it seems like I may have to get a posh etu.

I did wonder if id really notice given that were talking milliseconds...

You will notice the difference!

You don't need a posh etu; a Perun AB++ provides precocking and only requires rewiring although, assuming it is a V2 gearbox, if you are going to open up the gearbox to do that, you may as well fit an etu.

 

[ak2m4]

@Leo Greer have you noticed any PME with that build?  I'm just about to test a very similar build with one of my new 34k brushless motors  with a M110, fully stock no SS

 

[Leo Greer]

@Leo Greer have you noticed any PME with that build?  I'm just about to test a very similar build with one of my new 34k brushless motors  with a M110, fully stock no SS

I'm using an M120 equivalent with that build (PDI 190%), since I was getting slight PME on the stock spring (M115 equivalent). You can make it work with no PME though--I'm hitting around 29 RPS, and suspect I'm getting more drag than I should be somewhere, which caused PME on the original spring. I was able to simply use an M120 though, so it's irrelevant in my case.

TLR, yeah, you may have some. Depends on your setup though. It's right on the edge. I've done just as fast on 1J springs and been fine.

@Leo Greer From my measurement that is about 39 ms trigger response

The best I have seen in all of the internets is a 19 ms setup with a 28 TPA and m130 spring, unknown gear ratio (could be even 18:1) but that guy had somehow gotten a precocking that is literally the piston just sitting on the very last teeth before release, and the sound is just like a spring rifle because it really sounds instantaneous, sadly the vid was deleted and I could only dig out my reddit PMs for the numbers, but that was the theoretical peak of trigger response and I am so glad to have witnessed it, and it was better than every single youtube video or clips of people showing their trigger response, so that is the ceiling to aim for if there is one

What are you using to measure response? I'd love to try and measure the response on my 60+ RPS build...

 

[Pseudotectonic]

You can use Audacity to measure trigger response or ROF or even for general diagnostic by getting an idea of how it cycles.

Basically you can set it to record whatever sound you computer is playing, and you just click record and go watch a video and stop recording once you get the sound you need.

And then here is my method of interpretation and it works for comparison purposes:

View attachment 118599

View attachment 118600

 

[ak2m4]

@Pseudotectonic I like Audacity (very handy), one small caveat with rof though, if your bb's aren't feeding it will still measure them so can throw off results.