How many times can an autococker cycle per second?

[nerobro]

1/4"= .25"

ok.. radius times radius time pi..

.125x.125x(pi)=0.04908 square inches...

3/16"= wait.... eep... the math in my head just glitched really badly. I was thinking 3/8" *crawls back into his hole*

http://www.clippard.com/store/display_details.asp?sku=3SD-3T

Isn't that what the clippard rams are? not the minirams..... the fittings look the right size. if that's true... then it has 2x the piston aera.

3/8" gives us .1sq inch of aera... Doubble what the ram in the calculations gave us.. so we get doubble the force for the same pressure.

[Vegeta]

Re: actualy

"At 30 psi, the max rate I calculate is 19.5 cycles per second. Using the 1900 psi in Tom's post, I get a max rate of 155 cycles per second. The max cyclic rate varies with the square root of the pressure, all other factors (bolt mass, piston diameter, bolt travel) being constant. Quadrupling the pressure increases the max cyclic rate by a factor of two. "

155 cycles/sec. now lets calculate bolt mass into that. it is going to be harder to move taht block of aluminum back iand forth, tehre is a thing here on earth called gravity. In a vacuum, thats another thing. So that will slow down the cycles , but also teis thing has to reciprocate and therefore it has to accelerate in the beginning of each stroke, deccel when it is about closed,and accel again, etc etc. That will shave soem time off there. \


But what wetre looking for here is this:

A object with a mass of 500g when moving at 1 m/s is goign to have more kenetic energy than a object with a mass of 250g moving at 1m/s. i.e. it takes longer for a 18,000 poung 18 wheeler to stop than a 2,000 pound Nissan. Now taht recipricationg mass should be semi good, becuase at a certain spot it should start to help keep the cycling going thtat fast, i.e.bouncng back and forth. So makign hte bolt lighter will increase the cycle rate .. but how light is too light? will a medium wieght bolt give the cycling more enerygy than a lgiht bolt and therefore allowing the gun to cyccle faster?

I dunno. Now that I think about it, not really. But maybe if the bolt and linkage rod was lengthened, and there was a spring put between the block and hte body, so at high speeds it would bounce? no... thats nto a real good idea.. teh gun wouldnt stay in the cocked position.

just brainstorming here ppl dont kill me.

[bjjb99]

neobro wrote:
>
> 3/8" gives us .1sq inch of aera... Doubble what the ram in the
> calculations gave us.. so we get doubble the force for the same
> pressure.

3/8" is 1.5 times 1/4". The area will be 1.5 * 1.5 = 2.25 times that of a 1/4" piston, and will be able to push with 2.25 times the force at the same pressure. This means that the acceleration is 2.25 times as fast, which means that the time required to travel one inch is the square root of 2.25 times faster than for a 1/4" piston. The square root of 2.25 is 1.5, which is identical to the ratio of the two piston diameters. The cyclic rate varies proportionally with piston diameter, all other things being equal.

On the topic of max cyclic rate with an input pressure of 1900 psi, vegeta wrote:
> 155 cycles/sec. now lets calculate bolt mass into that.

I used a total reciprocating mass of 3 ounces, as stated by Tom.

> it is going to be harder to move taht block of aluminum back iand
> forth, tehre is a thing here on earth called gravity.

Gravity should not affect the reciprocating speed unless you're starting to talk about frictional effects against the bottom of the bolt's chamber.

> In a vacuum, thats another thing.

I'm confused. This did not follow from your previous sentance regarding gravity.

> So that will slow down the cycles , but also teis thing has to
> reciprocate and therefore it has to accelerate in the beginning of
> each stroke, deccel when it is about closed,and accel again, etc
> etc. That will shave soem time off there.

I took into account acceleration from a resting position for each direction of the stroke. Deceleration at the end of each stroke is the result of a hard stop, particularly in the case of the forward stroke. Because I treated the deceleration as a hard stop, I assumed it was effectively instantaneous.

> Now taht recipricationg mass should be semi good, becuase at a
> certain spot it should start to help keep the cycling going thtat
> fast, i.e.bouncng back and forth.

The only way you're going to get a bouncing back and forth effect is if you can find a means to store the kinetic energy at the end of each stroke and can vent the pressure that caused each stroke quickly.

> So makign hte bolt lighter will increase the cycle rate .. but how
> light is too light?

Absolutely. A lighter bolt should increase the max cyclic rate in proportion to the square root of the old bolt/new bolt ratio. As for how light is too light, I'd have to say so light that it affects the structural integrity of the bolt.


BJJB

[Vegeta]

When I mentioned gravity, i was talking about the bolt having wieght. And when I said vaccum i mean space, not vacuum... thats totally diffrent, sorry.

Now friction on the bottom of the bolt from gravity itself I wasnt directly talking about but could be an issue. I mainly meant that mass of bolt moving back and forth. What if the gun was cycling in a zero gravity enviroment? what effects would this have on the parts?

[AGD]

Well, things got lively didn't they?

AGD

[MrMag]

well i was just thinking and came upon this thought. running a pball gun at 90 fps would require constant oil on the bolt and internals to prevent too much friction. now unless he was pouring oil down into the gun durring the entire time, i dont see how this would be plausbale. the bolt and internals would create so much friction everything would simply be destroyed.

[pbjosh]

Okay, this is all fun and such, but a couple of comments,

Yes this got nice and busy fast. Way to go guys.

Uhm, 30 psi in a ram is rarely enought to cock it. Try 60-90 as the standard.

Also most Rams are made to run at 125-250 psi for a million cycles without lube.

The limiting factor for the total speed has more to do with other factors such as side load, hammer spring tension, total mass, and other junk. Just running the bolt back and forth at 70 psi or so still takes 15-20 ms each way on most guns without the cocking rod. I have tested an Open time to be reliable and cocking at the 20 ms level. But that was a really smooth setup. And at medium pressure.

If you set the Racegun to 7 ms for the open time the back block jumps about 1/2" to 3/4". Without a cocking rod it ALMOST might move close enough to load a paintball, if the back block was screwed out enough for the bolt to be almost at the breech opening when the the bolt was all the way forward.

Also if you use Racegun's RIP software the highest setting, at 1 ms for each or the 5 areas, you get 250 bps. The gun doesn't cycle at those settings boys. Just barely makes some really cool clicking noises.

I can get a gun to dry cycle at 18-22.5 bps, but that is with 1 ms to load paint. There is NO floating of the valve or anything, just a really fast angel scaring sound.

And the Racegun's Half-Blocks hammer, bolt, and top-block weight about the same as the standard fomieless bolt I have in my mag. I don't have #s, but it was darn close. I will try and measure when I get mine in.

As for timing the cockers with the Racegun Frame, You can test and set every portion of the grip to match EXACTLY how fast your gun does go. And sometimes that is alot slower than we think. I have sent guns out that could do 11.95 with a good VL and faster with a HALO. And ones that have an Eye that do even better than that. Most of them? 9.5 bps MAX. About 60% can do better than that. But I haven't seen any that run at less than 9.0 bps. Not a 1.

I will let everybody know what my Halfie does with an Eye and the Warp feed. AGD, got any any you want to donate for testing? I might not be able to hit 20 bps, but something close.

Josh

[orangejulius]

Josh

Im running racegun at 9bps. I am running a stock ram at 25 or its maybe around 28 ish PSI stock hammer just some special springs. I play all day like that and test it at home and it runs fine at that PSI loads fine doesnt pinch or chop in the whole day. running 250 shooting 290 stock bolt everything is stock besides the cocking rod P reg and the raceframe everything else is stock. Im feedinging it with a maxflow tank. and I dont even have a heavy hammer just stock.

[nicad]

as for weights..

a 2k1 STO backblock, bolt, and recocking rod are right at 109 grams. i actually made a bolt, backblock and recocking rod that weigh 27 grams, which is pretty much the same as the 25-30 grams of the shortblocks'.

with the stock STO 109 gram setup and a 74 gram tungston FF hammer, my race will shoot at 11 bps all day. have yet to try pushing the 27gram setup for speed, but it will do 13bps.

btw- PP/RaceGuns had some pretty nice setups at skyball 5 this year:

http://home.viptx.net/~colin/day2/03020039.JPG

pbjosh were you there??

out! :)

[pbjosh]

Nope, I was at Vegas, and should be at Chicago. And I will have a working Halfie there with one of Tom Kaye's Warps on it. I am hoping for 15+.

I should be hitting all the Major tourneis and some other events here and there this next year, and after that I will be VERY busy next year. I currently plan on hitting NWTS, Pan-Am, NPPL/PSP, and maybe all the fun ones inbetween, like Skyball, Mardi Gras, IAO, plus a couple of Racegun Events. Hopefull I will get to play in a big game or two, maybe some thing fun and senario. Right now I am busy getting everyting setup, but I will let ya know.

And hopefully I can see your gun.

Josh

[ER FFballa 8]

well

that is a vertibrate with a race i believe (actualy allmost positive..).. best race cocker i have seen/shot was ethans (from lockout) millenium race.. that thing was amazing.. mitchs son was lighting people up with it and hes like 10 it was funny as hell.. anyways back to the subject yeah like i said i run 30 psi to the ram and about 270 to the 'gun i get 10 on a slider.. planing on getting a race then pushing it to its ultimate max and then ill tell you guys what i got it to.. btw my cocker is a 2k2 boxxer ff.. next time i think of it ill throw the back block and bolt on the digi scale and tell you guys the wieght of it...

[Vegeta]

Damn this did get hot fast. I wish I had a cocker/racewframe so I knew more about this stuff.

[Grey_Goose]

I've had 4 RaceGuns, that all max dry-cycle'd at around 16-19bps.

They've been two Milleniums, Spanky Fishbone Mini, and Works, so we're talking fairly light markers & components.

Just from my personal experience, I'd say 30 or 300 is impossible, but we'll see where the halfie leads.

PBJosh, what inline were you using to get 22bps? I found that after about 14bps an ANS Gen-X couldn't keep up, and switched to a MacDev Gladiator.

Just as an aside to other RaceGun owners, I'm comfortably shooting 12bps, without any real need to see if I can tweak it to play faster. I didn't realize I could shave off some time on the Close, I might fiddle w/ that :)

Also, is anyone doing shot or dwell lower than 6?

[pbjosh]

Well, the guys at Compulsive Paintball Shot this vid and let me host it.

So, please, use 'Save Target As' to keep from slowing down the server.

http://www.amped-markers.com/video/racemovie1.avi

This is a Merlin Racegun with the Eye, running FA fed by a HALO. Notice he starts shooting at 10 sec, and stops at 21, and only has a couple of paintballs in the loader. The gun is set to 15.5, and he said it was hardly breathing, might have to open it up a bit more.

I have heard of a Warp fed gun going 18+ with paint, but at that speed you start worrying about parts falling off. as soon as I get my Half-Block, that is what I aim to shoot. I got the Warp, just need the Halfie.

Josh

[z-grip]

the boston paintball reflex trigger is capable of 14 a second. i know this becouse i just ordered mine. ohh god i cant wait