Radical bolt design; I need help

[infinitymag]

After hours of thinking, I think I have developed a new bolt system, but I have a few obstacles that need to be overcome. Below is a crude animation of the design:



Red: Paintballs
Yellow: Feed Neck
Purple: Bolthead
Orange: Bolthead
Green: Bolt Shell
Lavender: Flow Tubes
Pink: Vacuum Fan
Baby Blue: Barrel-to-Bolthead Connector?
Navy Blue:: Barrel Threads

Of course, I didn't post this just for your entertainment. Since this forum appears to attract many educated people who know what they are talking about, I ask, "What do you think?"

There is 2 major problems that I foresee; 1 being the drive system, how do I rotate the bolt shell as fast as a conventional bolt can cycle? 2 being the triggering system, how do I stop the bolt abruptly, but still make sure the heads and connectors are lined up so the ball doesn't jam?

There are advantages to this system. First off, blowback would forever be gone. Second, the vacuum in the upper chamber should help cycle the balls much faster than gravity would allow. Third, since there are actually 2 "bolts" a paintball would be fired in 1 stroke (1/2 rotation) rather than 2 on a convetional system. Last and my favorite, by replacing the boltheads and connector with different bore sizes (as in a freak barrel system), a chamber with a perfect paint-to-bore match could be created - resulting in better consistency.

If you see anymore potential problems and/or have suggestions, please inform me. I am cosidering drawing up a formal blueprint and having it machined.

[Aranarth]

Bolt

For problem #1: Look into the air assist feed that tippman has on their new guns. If you were to use air excess air to rotate the bolt, it may spin it fast enough. Add an electronic motor and belt to aid in keeping the spin if air is not enough. The only thing that I see is looking closely at how closely this resembles tippmans star feed thing, as it may be considered a boltless gun with a feed system internal to it.
For problem #2: Just add a ridge on the circle that a sear can hook onto, stopping the bolt in the correct (fired) position, like any normal sear/bolt combination. Would most likely be on the thin green pieces of your animation.
I agree that problem #1 seems big. #2 is easily surmountable. But I see another problem. Size. How big you figure this thing is going to be? Especially if you add a vacume fan, and possibly an electronic assist for the bolt action.
Good luck though. Seems like a cool idea. Especially having a removable bolt sleeve for paint matching. Since it is essentially a boltless gun, you wouldn't have any problems with breaking paint though. And depending on the force of the spin of your 'bolt', you might not have any chopping problems either.
Keep ideas coming.
-AranarthX

[infinitymag]

thanks

yeah i thought that maybe placing a solenoid between the lower flowpath and upper chamber could work. I never thought of the air assist though, thanks for the input. As for size, theoretically the green piece in the animation should be just over an inch long (remember this is a cut-away view, the green is also approx. 3/4 inch wide, or atleast as big as a paintball)

-infinitymag

[Redkey]

If you were to hook up a pneumatic ram to the revolving bolt it would solve the drive and alignment problems. When the ram is fully extended one chamber would be lined up... when the ram is retracted the other chamber would line up. Should be able to work just like how the wheels on old steam locomotives worked.

Also, instead of using a vacuum, you might be able to direct some of the firing pressure to the ball stack to give the next ball a little push into place.

As the bolt rotates what keeps the freshly loaded ball from dropping out of the bolt cup?

Perhaps if you rotated the whole assembly 90 degrees it might make it work a little better. Imagine looking down on top of it instead of looking at it from the side. That way the balls could drop right into the bolt and not have to be pushed in. Might make the gun a bit too wide though.

cool idea.

[thei3ug]

Or you could cut it so as the ram isn't permanently connected to the bolt, but there's an angled cut so that the ram extends, pushes the bolt, it gets locked by a clip, the ram retracts, ala spring returned ram powered by a "blowback" style valve.

[AGD]

That system has already been done (sorry). It was called the Phoenix and had a rotary bolt. It didn't rotate all the way around it only went 90 degrees from vertical to pointing forward. Gun had a short life in the early 90's with only a few hundred if that made.

AGD

[Wat]

Problem i see is getting the paint into the rotary bolt. If the bolt was big enough for the paint to easily get in, then you'd be firing paint from a loose breech. If you had a tight breech/bolt, you'll have problems feeding the paint into it as i don't see any mechanism that pushes it in.

[infinitymag]

Well, since the bolt heads would be interchangeable, there would be no problem pertaining to them being to loose/tight. As for loading, there would either be a vacuum in front or an air assist behind the queuved balls.

[ts1spoc]

Rotary Bolt

I knew the rotary bolt had been done on firearms like H&K's G3 caseless rifle, but I was not aware of the Phoenix or any painball guns using this design. Are there any schematics or pictures of it posted anywhere?

[Jack_Dubious]

Originally posted by AGD
That system has already been done (sorry). It was called the Phoenix and had a rotary bolt. It didn't rotate all the way around it only went 90 degrees from vertical to pointing forward. Gun had a short life in the early 90's with only a few hundred if that made.

AGD

I remember in the early 90's hearing the term "rotary breech and rotary bolt". But i wasnt sure the theory of the operation. I did overhear Glenn Palmer saying that there wasnt any future for it.


JDub

[Cristobal]

Re: Rotary Bolt

Originally posted by ts1spoc
I knew the rotary bolt had been done on firearms like H&K's G3 caseless rifle, but I was not aware of the Phoenix or any painball guns using this design. Are there any schematics or pictures of it posted anywhere?

Have Blue has got some info on it, go here:

http://airsoldier.com/~haveblue/tech/phoenix/

[AssassN]

That bolt would be mad easy to clean too.

[ts1spoc]

Thanks for the link Cristobal.

[Aranarth]

Aah. You've created a monster in my head. I was attempting to make this thing work. Wat had a very valid point I think. So, I went about solving this. My solution got more and more complex (violating k.i.s.s. (keep it simple stupid), of course). What I came up with, and think would work, is this.
Electronic of course, because the pneumatics would be hell for all this, and not sure if hose connections could be made.
You have the rotary disk. Use four sockets though. The thing rotates in the same way that infinity's does. The socket that faces up is the feed port. The firing port faces the same way as infinity's also. Got this picture? Okay, now each socket is larger than paint, like a normal breach. But each has a plunger at the back. The firing port terminates at the barrel. When the plunger is thrust forward, by a soleniod seems easiest (soleniods come later), it pushes the ball into the barrel. Springs return the plunger back to the recessed position.
This thing would have 4 (yes, the price skyrockets, but it was easy) soleniods. One for each plunger. The soleniods would be mounted on the sides of the rotary plunger, with arms directed inward to each plunger back. Two per side, 180 apart, controlling the opposite plungers. Their electrical contact would be closed only when the rotary wheel turned to the inline position for the firing port. The soleniod picking up would elgage a timing signal to the circuit board to stop the motor (discussion coming up) from turning. After a small time delay, enough for full plunger action, the soleniod would turn off, springs forcing the plunger back in. Or, a secondary method. Still trying to piece this one. Maybe some input here. One soleniod, mounted by the firing plunger. (centered in lower half of the rotary bolt, stationary) It would have a catch mechanism that would catch a projecting knob on the plunger, forcing the plunger in. Springs return as normal after cycle.
The method of turning the rotary bolt. After witnessing the belt action of both a halo and a warp feed, I like the idea. So, I take a motor, mounted behind the rotary bolt (makes the gun more balanced by placing the feed port more centered), attach a belt to it, and around the full circumference of the rotary bolt.
Now the final part. The air supply. This is very rough, and there is probably a better way to do it. How I had it set up is at the bottom forward part of each socket, there is a hole bored straight down. When in the firing position, this hole is lined up with the air supply. Way #1 (not sure) is for some sort of on/off soleniod in line with the air supply. But that would mean five soleniods, and two cycling per fire. That raises costs even more, and uses more power. Or, was thinking some sort of interlock with the soleniod firing operation, which would open a path for air flow as soon as the plunger reached the forward position. This may be possible, and more effective than #1.
I want some intense scrutiny on this part of it, though, because I am not satisfied on how it works.
Now some summary and big flick stuff. There are four soleniods (give or take some depending on design), and a motor on this thing. That causes a pricy gun. And for every shot, the motor cycles, and at least one solenoid turns on. The good thing, is each soleniod cycles only once every four shots (minus the air soleniod, if applicable). Since it has belt feeds, would it would solve the problem of chopping balls by the rotary, but would it jam. . . The firing port could be removable, making for adjustable bore sizing. As for gun mounting. The feed tube and the air port are in line vertically. That means you connect a regulated bottom line in the same places in front of the trigger grip as in normal guns. The rotary bolt would be somewhere between 1.5"-2" diameter. Depeding on how big the soleniods have to be, it would be approximately the same width as height. This would have to be vertical feed, unfortunately. The motor would be mounted directly behind and in the upper part of the gun body. Then you could mount a circuit board directly behind and below the rotary. And then a battery pack behind this. The back could probably hold at least 6 AA's. Or more AAA's. Maybe even two stacked C's. Or, if the whole assembly forward of the battery was small enough, you could have two rows of batteries in there. 12 AA's. Work into this integral power terminals for powering whatever feed systems you have. There would be nothing in the grip frame like most systems, except a switch to give a firing signal to the board. This makes you able to switch grip frames at will, as long as they have some sort of intellifeed output capability. The foregrip would most likely be a regulator. Think that covers most of the basics. Make the body out of aluminum also, and you have something that can be milled, since there is lots of excess on the back portions of this.
Thats plenty enough for now. Now to see about the pic. Yeah, its using paint. Someday, I need to get a real art program or 3d renderer, but I don't use it enough to justify the effort.

Link: Rotary Bolt Design
-AranarthX

[zads27]

Re: Rotary Bolt

Originally posted by ts1spoc
I knew the rotary bolt had been done on firearms like H&K's G3 caseless rifle

Interesting, seems a little complicated, though. If you think about it, all designs out in the marketplace are very simple. Not saying that it's not do-able in all the ideas you're thinking of, but when you're thinking of how to implement your idea, simplicity always makes things simpler.

And it was the H&K G11 caseless rifle, LMG11 caseless (light machine gun), and the G11 PDW (caseless handgun).