The scientific method for determining the effects of open vs closed bolt

[ProX9]

[SlartyBartFast]

I spent hella days writing this.

So are you going to do it?

WARPIG already did a fairly conclusive test by converting a Stingray between open and closed bolt operation.

But, the die-hard believers will still doubt the results. Glenn Palmer insists that closed bolt is better regardless....

[PumpPlayer]

You can simplify your data taking a little. Since you're not concerned with individual shots (which would be foolish as there are too many variables between paintballs, air density, etc.) and are going to be taking averages anyhow, just collect the average to begin with.

Use a piece of plywood or similar porous surface as a target. Make sure it is braced firmly enough not to shake or wobble when hit and ensure that the paint strikes it perpendicularly. It needs to be porous so the paint does not run down it as much as it would if you used something like a whiteboard.

Fire groups of 10 or 20 shots and record the overall diameter of the resulting mark. We can assume that over a great deal of testing, abnormalities in the splatter will balance out. With about 100 rounds from each marker (cleaning the barrel thoroughly between 10-shot groups), you'll get a decent average splat diameter.

Alternatively, you can use reballs with a piercable target. A piece of aluminum foil held tightly at all corners might work well. Make sure that it is held firmly and keep in mind that only high velocities will give you decent break-through.


Don't worry about ball drop and trajectory. Those things are not what you're trying to calculate and are a result of end velocity only unless there is some sort of backspin device used. Concern yourself only with spread size and pattern. Keep in mind that you'll need to truncate your results by dropping the lower and higher numbers to get a reliable mean.


You're looking for small groupings with few 'fliers' in order to determine the best 'accuracy'.



HOWEVER - keep in mind that any benefits of a closed-bolt system are mitigated once you exceed about 10 bps. The bolt is moving so fast anyhow, it doesn't really matter whether it's open- or closed-bolt.

Good Luck!

[ProX9]

I actually am concerned with individual shots, as long as I have a velocity to associate each impact position of a ball I can basically see what would happen if my guns velocity never fluctuated at all. All I have to do is get an an average drop for each different velocity and then I can compare results. I would also plot the impact data on a graph which would be the same as the target, so i have the benefit of both averages.

[deadeye9]

The variances that occur firing a paintball:
1) out-of-round paintball to paintball variation
2) shot-to-shot velocity differences
would swamp any differences that would be caused by the bolt configuration.

[CaliMagFan]

The variances that occur firing a paintball:
1) out-of-round paintball to paintball variation
2) shot-to-shot velocity differences
would swamp any differences that would be caused by the bolt configuration.

solved by... use of reballs... and chronoing each shot fired...

remember, this is an experiment to find if one is really better than the other. It's not really a super-real world scenario.

[ProX9]

I dont even have to use re-balls since id be shooting enough shots to be able to eliminate outliers and still have a large number of shots to base my data off of. The velocity differences are also negated because id only be grouping the results from each different velocity, eg only the coordinates for shots that went 288 fps would be used to compare with the other gun's shot's that went 288 fps. Please read the actual experiment and then the meaning of each part before you criticize, suggest, or post anything pertaining to it.

[CaliMagFan]

I dont even have to use re-balls since id be shooting enough shots to be able to eliminate outliers and still have a large number of shots to base my data off of. The velocity differences are also negated because id only be grouping the results from each different velocity, eg only the coordinates for shots that went 288 fps would be used to compare with the other gun's shot's that went 288 fps. Please read the actual experiment and then the meaning of each part before you criticize, suggest, or post anything pertaining to it.

your projectile will be "consistent enough" if you do eliminate the clearly extraneous ball or 2... but the use of reballls would be more scentifically correct, cause the projectile is still a variable.

[VFX_Fenix]

Or you could get these things called "Perfect Rounds" which are often used in accuracy tests by companies that make paintball guns for things other than paintball (like Pepperballs). Perfect rounds are plastic shelled .68 cal "paintballs" that are filled with water and are supposed to be the best thing out there for consistantly spherical paint.

This sounds like overkill, but hey, I'm curious and if its overkill, that's generally a good thing. Have Fun!

Physics don't lie

[ProX9]

Ill be using good paintballs, another point to this test is to see if actual paintballs can be used and still show a discernable difference despite the inherent problems with using actual paint. Make sense?


3. The paintballs were too imprecise to draw any conclusive results between the amounts of drop for each gun, which leads to the conclusion that paintballs are imprecise enough to void any effects provided by the firing method and it does not matter which method of firing your gun uses. (If this experiment is done with high quality paintballs this statement is further proven because it can be assumed that most paintballs used in real world situations are of lesser quality and thus suffer further from the effects).

[VFX_Fenix]

yeah, I saw that, I was following up on the guy above me who sudgested ReBalls.

[spacedtedybear]

It's really late, and I need some sleep. So instead of rambling on about physics, I will say; you forgot to include the atmospheric pressure readings, density of paintball..... must sleep.

[tyrion2323]

Welcome back to 1998...

[Maggot6]

Good idea.

[johnson88]

i was thinking latley about why everbody says closed bolt is more accurate and i might have come up with a reason this is said. It may sound stupid but its just a thought. Here it is: the ball is shot millseconds before a open bolt shoots because it does not have to wait or the bolt to come, this would make there shots go closer to a moving target or while you are moving go closer to where you want it to( i know this could be fixed by knowing shoot were there going but people who think they are more accrate are not informed and probably ouldnt be informed about that either), But closed bolts will not have straighter shoots more range or accuracy everytime this comes up it is proven that they are the same with the same results.