Dwell and efficiency

[funeralplanner]

Does efficiency change with dwell settings?

[RRfireblade]

Of Course.

Dwell is basically the amount the time the valve is open so changing that effects how much air pases thru.More then or less than the 'ideal' amount will have a negative effect on efficiency...generally speaking.

[Lohman446]

Simple answer: Yes

As long as no other changes are made than efficiency is inversely correlated to the dwell setting - higher dwell less efficiency.

I think

[FallNAngel]

What Lohman said is correct for guns that actually have a pin-valve type system... basically anything that has a hammer hitting a valve. On guns where the air supply is cut off when the bolt is forward, such as some bolts on a Matrix, etc, then it only affects it to a point. At a certain point, all of the air that should be vented, will be. After that, you're just affecting ROF. If you lower the dwell below that point, then you'll increase efficiency, but also lower velocity.

For pretty much every situation though, dwell is inversely linked with efficiency.

[AzrealDarkmoonZ]

There is no direct wide ranging rule that can be applied to the correlation between Dwell and Effeciency. Like most things it more than likely follows a bell curve, ie 5 dwell might be to little and you have to raise pressure to compensate, and 20 dwell probably wastes air.

Az

[FallNAngel]

There is no direct wide ranging rule that can be applied to the correlation between Dwell and Effeciency. Like most things it more than likely follows a bell curve, ie 5 dwell might be to little and you have to raise pressure to compensate, and 20 dwell probably wastes air.

Az

How is that a bell curve? If anything, it's just diminishing returns with velocity. Other than that, dwell is directly linked to efficiency in most circumstances. I don't see how you're getting a bell curve from this...

[funeralplanner]

Thanks for the replies.

I was thinking the same thing, but wasn't for sure. I just got a promaster, and was changing the dwell and it was changing my velocity a little as well. I went from 7 to a 9. I can't tell a great deal in speed, who could, but that will hurt my efficiency a little too. I probably won't even notice it.

Let me throw this out there.

What will get the best efficiency, in theory? High psi HPR say 300 with a dwell of 7 or a Lower psi HPR around 200 with a dwell of 9 or 10, or even higher?

I'm going to test this out somehow, just wanted to know what to look for and test. I'm testing this on my promaster by the way. From what I know, the hammer hits a valve, kind of like my old cocker, so the dwell, would make a difference.

Thanks for the input.

FP

[manike]

What will get the best efficiency, in theory? High psi HPR say 300 with a dwell of 7 or a Lower psi HPR around 200 with a dwell of 9 or 10, or even higher?

High psi HPR say 300 with a dwell of 7

Not just theory either. I've tested it.

[AzrealDarkmoonZ]

How is that a bell curve? If anything, it's just diminishing returns with velocity. Other than that, dwell is directly linked to efficiency in most circumstances. I don't see how you're getting a bell curve from this...

I was assuming velocity stays the same, else at 1 dwell your effeciency is going to be maximum since you won't actually be firing a ball.

Given they we keep velocity at a set limit (280 fps), and we are testing for effeciency, then the maximum eff will be at the point at where the air no longer has a significant impact upon the ball in terms of FPS. Anything above that is wasteful, and anything below that is more than likely not firing the ball at 280 without pressure change.

For instance Manike states 300psi and 7 dwell for I will assume a timmy and that , that is the perfect setting (for arguements sake). Lower the dwell 1 and velocity goes down, so te reg must be raised to compensate and eff will more than likely lower. Increase the dwell and you get more wasted air.

That 7 dwell is the top of the curve, 6 and 8 are slightly below the top. Granted I am not sure if it is an evenly distributed curve so YMMV.

Az

[FallNAngel]

For instance Manike states 300psi and 7 dwell for I will assume a timmy and that , that is the perfect setting (for arguements sake). Lower the dwell 1 and velocity goes down, so te reg must be raised to compensate and eff will more than likely lower. Increase the dwell and you get more wasted air.

I see what you're trying to do, but now you're messing with several factors (dwell and air pressure)... I was (as you were stating), trying to work with just dwell

[funeralplanner]

Its going to be tough, if not impossible to know, so, I'm just going to set this promaster on dwell 7 and around 275ish and see what happens. I learned a little more about the gun talking to a tech a little while ago. Thanks for all the help. I'll let you know how it goes.

[AzrealDarkmoonZ]

If you work with just dwell though 1 will be the most effecient setup since you won't actually be firing a paintball. At 4 dwell your gun will be more effecient than 6 in a literal sense, but you might only be shooting 180 fps. I suppose a more adequate effeciency rating would be something like (Number of balls shot) * FPS, if there is a linear relationship.

Az

[FallNAngel]

Its going to be tough, if not impossible to know, so, I'm just going to set this promaster on dwell 7 and around 275ish and see what happens. I learned a little more about the gun talking to a tech a little while ago. Thanks for all the help. I'll let you know how it goes.

I think Azrael and I (well, I know I was) were speaking more in general terms. If Manike says to go with a Dwell of 7 and HPR at 300psi on the Pro-Master, then go with that.

[funeralplanner]

Thanks for everyones input!!!

[manike]

It's a good point that we are looking to maintain velocity while adjusting the dwell and pressure.