X-VALVE SPEED TEST = AVERAGE 32.7 CPS! (pic and sound)

[yagrmiestr]

What's the big secret?? If you remove your on/off o-rings the dump chamber never seals and your gun goes full-auto when you pull the trigger (releasing the bolt).

Nothing personal Jack, but these kinds of threads always come off as a little arrogant to me. I mean, the internet is all about sharing information, not holding it above everyone because you don't feal they are responsible enough to know something. Again, I'm not attacking you, especially since you promised a friend not to tell. Just my opinion. In fact when the new tinkerers forum shows up I will be happy to post the source code to MY (not hacked AGD code ) emag code. Afterall, it's all about sharing the fun we have with our mags!!

- Jeremy

Edit: Sorry if I came on a little strong Jack, I now know you were told not to post how to do this.

[Dave]

yagrmiestr-

I've actually had this happen as well...I think it happened with me just using one o-ring in the Emag valve instead of the double setup... but I'm curious-is the sear still contacting the bolt?

-Dave

[yagrmiestr]

What's happening is that the sear releases the bolt and normally closes the on/off so the dump chamber is cut off from the regulator. If you remove the on/off orings the on/off pin will be in the closed position, but not seal the reg from the dump chamber. If you hold the trigger down the gun will continually fire becuase the bolt is released but the chamber still recharges because the on/off is not sealed. Make sense??

I'm only assuming (you know what they say about that ) this is what Jack did because he said he did not modify anything and this is the only way I can think of that the gun would continue to cycle with the trigger held.

[Dave]

I guess it makes sense if you hold the trigger down all the way ( as I did do when only the single o-ring was in the Emag valve) and the front part of the sear never engages the bolt because the trigger rod would be coming back out as the sear engaged the bolt lip...I guess I answered my own question. When I did this...I estimated only about 20 cps though ( lol, I know, only 20 ) when Jack and Coke gets 32. Granted, he has an adjustable, but he said with it adjusted down to 600, he was getting 21 cps, and my tank runs at 850.

-Dave

[yagrmiestr]

Sounds like you got it figured out Dave. Maybe try a different bolt spring, but like Jack mentioned, it's rather uncontrollable.

[askman]

The key is to use high pressure and strong bolt spring for highest rof, using the lightest moving parts(ie bolt). Taking the O ring out of on/off, is like taking the disconnector out.(turning semi auto gun into full auto in the open bolt gun)

[Butterfingers]

Wow that must be hell on the internals...

Just to set the record straight this was not what I was thinking when I said to swap the internals out of an OEM gun.

this actually could be quite dangerous...

My guess is that you wont be able to get this thing to feed even at a lower BPS. Free cycling by definition leaves no open bolt dwell for the ball to drop into the chamber. For reliable feeding you need a sear lock on each shot.

[Jack & Coke]

Originally posted by Butterfingers
...Wow that must be hell on the internals...

I've been studying this for a couple days, and I honestly don't think it's as "hell" on the internals as you think.

I believe this type of setup slightly increases the wear on the bolt and sear... but maybe not in the way you think.

The only moving parts during full-auto are the bolt and main spring. The pressures these parts experience are no greater than normal operation... it's actually less stress but more frequent.

The bolt is the only thing cycling. Not the rest of the internals. When I spoke of CPS, I tried to make clear I was referring to how fast the bolt/valve system is, not the "gun" as a whole.

On the first shot, the bolt moves forward at normal speed and pressure.

It compresses the main spring and impacts the front at normal speed and pressure.

It returns to the rear striking the bumper on the valve at actually less pressure than normal.

Why less?

Because under normal operation, the valve is closed via on/off pin, this provides no resistance to the bolt as it slams rearward by the main spring.

If the valve is always open, then the air being expelled during the return stroke of the bolt actually slows down the speed and force of the returning bolt.

Since the sear NEVER touches the bolt if the trigger is held back, it will not experience any wear from the bolt during THIS stage.

Since the sear is not grabbing the bolt, the bolt immediatly moves forward into it's next forward cycle after impacting the bumper. This is why it is the fastest possible setup for testing MAX CPS. The bolt NEVER stops moving.

Here, the air pressure pushing the bolt forward, is LESS than normal opperation since the valve never closed. If the valve never closed, the dump chamber pressure doesn't really have a chance to build up to normal opperating pressure.

The situation where I think a minor increase in wear may occur, is each time you release the trigger.

During NORMAL opperation, each time the trigger is released, the sear engages on the bolt, holding it in place and "capping" the dump chamber (i.e. power tube).

It is here where I think wear may occur (on the bolt and sear) during this "speed" setup - It has to "catch" a MOVING bolt. Whereas during normal opperation, the bolt is not moving when the sear engages.

HOWEVER, although the sear has to "catch" a MOVING bolt, the "impact" of the bolt to sear is probably minor since the distance the bolt moves forward prior to being stopped by the sear is very very small.

At a small distance, the bolt doesn't really gain as much momentum and impact force, as it would if the sear were to catch the bolt further in the stroke.

I have checked my sear and bolt many many times over the last few days since doing this setup, and so far so good...

I don't plan on always running my mag this way...

Since I believe this setup does, over time, cause minor wear to the sear and bolt, I can't encourage anyone doing it.

Maybe every blue moon when I'm being bombarded with pro-Angel-Cocker-aniti mag smack talk at my local pb store, I'll givem a little sumtin' sumtin' with a 32 CPS demo...

or maybe even if I'm cleaning the garage and I need to blow all of dust and leaves out!

edit: typos

[LoveMyMagMoreThanYou]

All I can say is WOW!!

[Jack & Coke]

UPDATE!

Video Clips are up!

Check em out here:


Automag MAX CPS (4 MB mpeg)

Automag Sweet Spotting the Trigger (4.8 MB mpeg)

Thanks and big ups to Gadget for hosting these clips!

[Frank (the spank)]

that was badass!

hmmm... two warps. halo.. think it could feed 32bps in short bursts? Now that would look cool!

[ZyperioN]

um i dont know maybe im the only one that caught this but..

8 cycles in 0.2 seconds = 40cps!!!! not 32cps

[Jack & Coke]

Originally posted by ZyperioN
um i dont know maybe im the only one that caught this but..

8 cycles in 0.2 seconds = 40cps!!!! not 32cps

It's the first sample... 8 cycles in 0.229 (not 0.2) = 34.9 CPS.

It was the fastest string I found.

32-33 represents an AVERAGE.



I can make it faster if I boost up the input pressure to 1100 psi.

[Teen]

ok everyone i've figured out how u do it. there are 2 ways of doing it. ok, i'll explain.

the first way only takes one word to describe how to do it..... "SPEED", take some speed, and wait till it kicks in, then go rip on your mag.lol

the second way if less dangerous because it doesn't involve drugs. first get a rope, then some weights. tie a knot at one end of the rope, then slide some weights over the rope. then put a loop at the opposite end of the rope, so that it will fit your index and middle finger. then start exercising your fingers, up down up down up down. lol

unless your stupid i wouldn't try either one of these especially the method about take the speed, although that one might work lol. i just posted this cuz im bored and i thought it was funny, now that its out of my system i think i'll go to sleep.lol(hhhmmm i wonder if i got anyone excited before they read the rest of this post after the first paragraph.)

[Peach]

yeah... When I was figuring out which size of pin to use on my minimag RT... One of them broke.. I was smaller then the emag pin, and MAN it ripped about as fast as jacks. Couldnt shoot balls worth *POOF*. First ball would fire and the other one would just bobble on the bolt. Mine can do about 15bps right now(so the hopper can keep up). I Played with it on around 20 a few times when I confiscated a ref's halo