Closed v. Open (Bolt)

[Minimag4me]

i agree that on a cocker closed bolt is an advantage because it was designed that way. YOu can make an open bolt cocker pretty easily but you will see negitive effects. On mags for example open bolt works best and closed has disagvantages(like not being able to operate).

In truth all markers fire in a closed bolt position.

[clockworkmiller]

not really, senior minimag4me.

A closed bolt gun fires without any blowback. This is because the bolt is as forward as it can go when the gas is released.

With an open bolt gun, the gas is released while the bolt is moving forward, causing some of the gas to travel up into the feed.

[Minimag4me]

ill use tippmann as an example,

the bolt moves the whole way forward(guide spring) and pushes the ball into the barrel. At the most forward position the hammer hits the valve pin and releases the gas behind the ball and the bolt/hammer steup recocks. This happend on all open bolt blow back guns. The exception is on blowforward like mags i think they have thee power piston length set so the gas is released when the bolt is pretty far forward(probably not completely closed bolt but close enough with the long nose bolts)

blowback is just remaining air in the breach(or prereleased air in shortnosed bolts). When the bolt moves to the cocked position it can go into the feed tube causeing blowback. ON a cocker(any closed bolt gun) by the time the bolt goes back to load a ball there is no extra gas in the breach.

[BlackVCG]

Minimag4me has the idea down. The bolt stem is designed so that the pressure is released at the end of the stroke. The current PT tip with the taper is designed to release the pressure over a longer interval. The old PT tip that was counterbored released the pressure in a quick burst. You can basically control how you want the pressure released and at what time by changing the design of the PT tip.

The I.D. of the PT tip is critical also. Take a spare PT tip and drill it out 1/16" larger and observe the results. It's quite interesting. :)

[Jonny05]

Still wondering...

Have paintball markers become as accurate as the can be?

Well due to the fact no one agrees with my "ball jump" factor I was thinking of maybe the only other thing is to change the paintball design. I thought there were seemless balls that a whole bunch of campanies are working on. Thoes would be great in the Z-bodies and flatlines.

Thinking about it the only way you can get more accuracy is make a conical (sp?) shaped projectile then spin it like in a armson barrel. It would kinda be like a fooball/bullet. Or even better then that, a sabot (hourglass shape) shaped paint. Like the new slugs by Winchester arms. (Its gotta scare some pballs by saying that)

Naw it will never work. Paintballs will allways be
paintBALLS.

Oh yea... If anyone does the tests on ball jump tell me how it goes.

-JONNY

[clockworkmiller]

Paintballs will as be spherical. This is because it is the easiest to load, and the most painless when getting shot. A solid front or a pointed front would definately be more prone to injury and also have to necessitate a completely redesigned gun, loading system, and rules.

[Jonny05]

yea...

That is why I said it would never work. I think balls are the best idea.

But FYI the sabot (what winchester calls them) is shaped like an hourglass and has no point thats why I said it would be better. So it is like two cones faceing into each othere and the end(s) are rounded/flat.

I thought SP, WGP, and AGD have been testing seemless paint. Same with RPS but I heard all that from not-so-good sources.

[Vegeta]

"To me, Bud Orr isn't innovative.. he was just a tubby guy who didn't wanna pump his WGP Sniper II so he put a ram on it. OOOooooooH! Tubalard at work!"

BTW I did mention the pump in my quote there. lol.

So it pumps itself. Its like two machines in one and therefore its not really semi auto. Its like putting mechanics on the pedals and steering wheel off a car and controlling it with a computer. Is the car really driving itself? No, it has a computer sttering it. Two diffrent mechanisms. Just liek the ocekr. automated pump.

[Manuel_FZR]

[IanR]

i just wanna throw this in and say: " a paintball gun will only be as accurate as its ammunition" this is true with all "real" firearms too. thats why really high grade paint is more accurate then crap paint even if both are matched with barrel perfectly. by good paint i mean seamless,heavy fill,consistent in size from ball to ball (as much as possible) just my thoughts

later

[Vegeta]

BLACK U TOTALLY RUINED MY QUOTE!

eh.

There will be new ideas. No one has mentioned a Trap Door boltless feed here yet. (I.E. the Epic) I'd liek to hear some arguements on that.

[deded]

Since this is deep blue after all... I figured I might mention some physics

I saw a post by Tom a while back that said that no deformation was seen on the dyno and with high speed photography or something... so this is probably totally wrong.

All quotes are from Physics: third edition by douglas giancoli.

In a collision of two ordinary objects, both objects are deformed, often considerably, because of the strong forces involved

It seems that this would make a closed bolt design more accurate then an open bolt design, except for at high rates of fire. I.E. The ball is pushed into the chamber and deformed, but has time to reshapen before the blast of air pushes it out of the barrel... where as the open bolt hits the ball, deforms it, and then instantaneously shoots it out the barrel, possibly not allowing the ball to re-round as quickly as the closed bolt would.

But, as no deformation was detected with high quality instruments, maybe the deformation happens for such a short time that it does not effect the accuracy of the ball at all.

If this is true, then "trap door" style boltless designs don't have much of a use... because it seems like the trap door could chop a ball just as easily as a bolt. However, a boltless design may have less precoil and recoil.

The million dollar question... what will make a more accurate paintball marker? I think the answer is: eliminate the possibility of user error. In the angel forum on pbcity, there is a guy complaining about bad accuracy when he reaches high rof. I think that this is because he is trying so hard to shoot fast that he is wobbling the angel all over the place.

So the million dollar project that AGD could design: intellifire!

[Jonny05]

HAHAHA...

I can get a brain wave to micro switch adapter at Walmart right?

Though something like that would be damn cool it would be dangerious. There is actually people working on computer games that are controlled by your brainwaves.

But back to accuracy in paintball...

Another thing I think causes good accuracy is a short soft trigger pull. There is less jerk and no strain when you pull. I do a bit of plinking and one of the fist things you learn is to exhale takeing the shot and squeese the trigger- don't jerk it. With electronic triggers it is easy to come by but still some people still screw it up by fanning.

MORE SATURDAY RAMBLINs'- where are my phy. notes.

Wait a sec deded... how does a ball become deformed being pushed into a barrel??? Nothing is collideing in your gun when you fire because one object (the ball) is at rest. The ball has very little resenstence when struck by the bolt. So the ball will be put in motion by the greater force acting on it. After it is in motion it will want to stay in motion- the only other force is the gas, bore resistance, then the usual gravity/air resistance. If anything it will be the gas that causes the deformation because of its greater force. But here is the thing- balls can handle the force.

So what I'm basically saying is the bolts force will not do any harm to the ball because it is smaller compared to the force of the gas.

any arguements?

-JONNY

[deded]

no arguments

but....

I'm reading straight from the book here, and trying to interpret it as best I can to apply to the subject.

It is basically saying that everything is deformed by a collision. (and it is a collision... regardless of the fact that the paintball starts at rest) Even the bolt is deformed an enormously minescule amount... if I'm interpretting corectly. But, like I said, it probably all happens so quickly that it has no relevence to accuracy.

I think that the bolt must exert a good amount of force on the ball, just to move it into the barrel so quickly. And look at what happens using only the force of the bolt when the ball isn't loaded all of the way into the breech!

I personally don't believe that closed bolt (cockers in particular) shoot any straiter then open bolt. I think that some people say that cocker's are more accurate because they don't want to admit that they bought an expensive marker just because its cool and it looks good.

I own a cocker (because its cool, and it looks good) and I can't shoot it any straiter then my mag or angel. It actually shoots less accurate because I never really learned the trigger, and I wobble all over the place trying to get the ROF that I can pump out of my mag/angel.

I think we should use the collective brain of AO and deep blue to think of something that AGD might be able to develop to raise the bar of accuracy/precision in paintball!

[kilaueakid]

Reffering back to what Lord Vader said about the accurracy thing in relation to speed of the bullet in a hand gun and how it is more accurate because the bullet has left the barrel before the recoil happens.

So than in therory, wouldn't a shorter barrel cause less recoil and therefor be more accurate because the ball will be out of it sooner?? Like a 14" vs 8"?

We should get some of the math wizards to figure out how long of a barrel you would need for the ball to leave before the bolt cycles back to the cocked position.

That would be interesting info.

kila