yea im a little confused about this. as some of u may know ive owned a cocker and cockers open to let a ball fall into the breech rather than letting the ball fall in whenever it can. this is what ive always thought closed bolt was (pull trigger, bolt opens, ball falls in, bolt closes). but when i was pballing a little while ago, i was talking to some ppl (walk-on with a timmy and an angel, and an employee with a trix) and i told the employee that i wanted to get an alias. he said "nah i dont like open bolt design because its a little less accurate." i had heard that trixes were closed bolt before. "and thats why u have a trix?," i said. "yea," he said. later on i was playing with the kids LCD, and the employee said "that angel is closed bolt too," (something i never heard before). "it is?" i said. "yea, do u see a bolt at all?" he said. this confused me because at that point i was debating about the meaning of closed bolt between what i had thought before (pull trigger, bolt opens, ball falls in, bolt closes), and the definition of closed bolt being no bolt exposed.

so all i am asking you guys is, does closed bolt mean what i thought it did, or does it mean that the bolt is completely enclosed (like an angel or a trix)????

thanks in advance,

jake

C:  None of those.  Almost all paintball guns open the breach by retracting the bolt, allowing a ball to enter the breach, and the close the breach by pushing the bolt (and the ball) forward, allowing the gun to fire.

The difference between "open bolt" and "closed bolt" is the resting state of the bolt and the firing sequence. 

Open bolt (Tippmann, Spyder, Angel):  Pull trigger, bolt closes, gun fires, bolt opens, ball enters chamber.

Closed bolt (cocker, pump gun):  Pull trigger, gun fires, bolt opens, ball enters chamber, bolt closes.

When you are done pulling the trigger on your cocker the bolt is closed and ready to fire.  On a Tippmann, the bolt is open until you pull the trigger.

Despite claims of cockers owners, there is no meaningful evidence that closed bolt is "better" than open bolt.  Even if there were a difference, that difference would go away at 20bps anyway.

An Angel, however, does have an "enclosed bolt," meaning that (unlike a Timmy/Spyder/cocker) no part of the bolt is on the outside of the gun.  This is handy for playing in the dirt.

There have been many test done and the proven fact is that closed bolt guns are no more accurate then open bolt guns at any ROF. People who think thier cocker is more accurate then Angels because its closed bolt is only being foolish and falling into Bud Hores BS hype.

ImpyKing2 wrote: There have been many test done and the proven fact is that closed bolt guns are no more accurate then open bolt guns at any ROF.

Not true.  There have been some tests, with questionable procedures and even more questionable general application.

Yeah for some reason lots of people think that An open bolt means the bolt is not enclosed.  I was talking to my friend about cockers and how they were closed bolt and he was like, "yeah same thing with Angels."  I wa thinking no.  I was right.

WooHoo.

Well this just confirms what  I figued

Good for me

Clark Kent wrote: I agree, Greg - I have certainly never seen any meaningful difference between open and closed bolt accuracy.  I was simply commenting on the somewhat strong statement that it is a "proven fact" that there is no difference.

It isn't proven eh...maybe you should read some of the test done then you'll see that it is proven that there is no difference in accuracy or perfornace in closed bolt guns.

ImpyKing2 wrote: Clark Kent wrote: I agree, Greg - I have certainly never seen any meaningful difference between open and closed bolt accuracy.  I was simply commenting on the somewhat strong statement that it is a "proven fact" that there is no difference. It isn't proven eh...maybe you should read some of the test done then you'll see that it is proven that there is no difference in accuracy or perfornace in closed bolt guns.

Why don't you point me to the studies in question, then...  (I presume you mean the pbtimes study?)

And then go look up "proven fact" in the dictionary.

rednekk98 wrote: The fact is that if you have a heavy mass moving prior to the shot, it's going to throw off your initial aim. But this is of course moot when you're firing a string of shots. It effect first shot accuracy only, but depending on the gun, not by much.

But what you are suggesting is user error, so to speak.  If two clamped guns would perform the same, and the difference is caused by a shaky gun, is it really fair to say that one gun is more "accurate" than the other?  Isn't the better statement that "this gun is easier to aim"?

"Accuracy" is a bit of a tricky concept in paintball.

http://www.pbtimes.com - www.pbtimes.com

http://www.warpig.com - www.warpig.com (I can't see how you can argue this one. It was done right and it was done from a clamped down table so nothing could affect accuracy excpet the gun itself)

Also they don't have phrases in the dictionary...moron.

Ok - back to remedial science class for you.

That was the study I was thinking of, and it, by itself, does not support your claim of a "proven fact."

It may be enough for "you to believe," but that isn't a very high standard.

Like I said, back to remedial science class for you.  Once you understand how the scientific method works, you will understand why you are wrong.

Good god, you just don't understand metaphors or rhetorical statements, do you.

By the way - what was the standard deviation on the shot spread in that study?  I also missed the part where they mentioned the level of statistical significance.  What was their alpha level again?  And what do you think the external validity of the study is? 

Please.

Why is it so hard for you to admit that you are wrong?  If you actually understood my last post you would also understand why that article is practically worthless.

Good god - can you even read?  What exactly do you think that I am saying?  If you want to argue against imaginary points, that is fine, but please don't attribute statements to me that I did not make.

You know, the main reason why your credibility is so low is that you keep making outlandish statements and refusing to back down.  You just make yourself look silly?

†Sniper† wrote: he won't admit he is wrong because he is an ass, and because you are acting like an ass.

lol - fair enough, I am being a bit of an ass.  IK2 just brings out the best in me.  My apologies to all other incidental readers.

:)

Clark Kent wrote: Good god, you just don't understand metaphors or rhetorical statements, do you. By the way - what was the standard deviation on the shot spread in that study?  I also missed the part where they mentioned the level of statistical significance.  What was their alpha level again?  And what do you think the external validity of the study is?  Please.

4.

While I have neither the time nor the inclination to conduct actual experiments, I can briefly explain some of the problems with the WARPIG study.

First - what are we studying?  As red hinted at, "accuracy" is relative.  The WARPIG study clamped their guns, but if recoil (for instance) is an element of accuracy, then clamping probably isn't correct.

However, for purposes of this discussion, I propose that the "accuracy" we are discussing excludes all human factors, so I will assume a clamping scenario.

Second, we need an operational definition of "accuracy."  The WARPIG people measured max spread.  This, IMO, gives unfair weight to a singel outlier.  I would suggest that all shots are measured, and measures of variability be determined based on individual distance from the mathematical center.

Third, actual statistics would have to be run.  The WARPIG people observed that 11.5 inches is more than 11 inches, "but not by much."  That is insufficient for a scientific study.  The statistical significance would have to be properly established (or not established), using any of several available statistical tools.  Of course, 20 shots is nowhere near enough shots to create a suitable statistical baseline.  Hundreds or thousands of shots would have to be fired for the mathematics to be reliable.

Fourth, numerous confounding variables would have to be accounted for.  Shots should be fired at different ranges, using different barrel/paint combinations (perhaps even a Flatline), at different elevations, using HPA and CO2, etc.  High pressure and low pressure guns should be employed, as well as some high performance guns.  An Angel or a B2K with a Morlock board, for instance, can be set to fire from closed or open bolt, and would presumably show better accuracy than a Stingray.  As it stands, there are too many variables that could affect the results that have not been accounted for.

Finally, the study would have to be replicated.  It is central to the scientific method that a study must be replicatable before it is legitimate.  A single study never leads to a "proven fact."  A single study only leads to partial evidence.

Bottom line - the WARPIG study was an admirable but hopelessly amateurish first attempt at scientifically addressing open v closed bolt discussions.  It does provide some useful information on the subject, but should be taken with a great big grain of salt.

BTW - air flow in the room cannot be controlled completely, but the study should of course be conducted both indoors and outdoors, to determine whether wind affects one type of gun more than the other.  Beyond that, assuming that the air flow is generally fairly consistent, the affect thereof on any given individual shot (and the effect of a myriad of other minor confounding variables) would be accounted for mathematically by simply firing thousands of shots instead of 20.

Easy.

First, proper statistics.  WARPIG found a 0.5 inch variation in spread.  With a 20-shot sample, this may or may not be statistically significant.  We won't know until we do the math.  And to do the math meaningfully, we will need a lot more than 20 shots.  It is almost impossible to show statistical significance with 20 shots. 

Second, while the difference between 11 inches and 11.5 inches may be "not much," perhaps if we used an Angel we would get shot spreads of 2 inches and 2.5 inches.  Still 0.5 inches difference, but now suddenly it looks important.  This is why we must use different equipment.  Stingrays aren't exactly representative of all other paintball guns out there.

Third, why just measure spread?  A single outlier skews the entire variability calculation.  Which is more accurate - a gun that fires an 11-inch scattershot spread, or a gun that fires 19 balls on top of each other with a single 11-inch outlier?  I say we have to measure every shot.  Unless, of course, we are just testing whether closed bolt operation leads to fewer outliers.

Fourth, barrels - if the theory is that the forward-moving bolt affects the ball, then it could be important whether there is a tight barrel fit for the paint, because a tight fit might counteract whatever the bolt does.  Maybe open/closed doesn't matter with a good fit, but does matter with a small paint/large barrel.  We won't know until we check.

Same for wind - maybe closed bolt operation is more or less affected by wind?  This argument has been brought against Flatlines for years.  Same for distance - maybe closed bolt is only more accurate at long ranges?  This discussion has been had about barrel length for years.

Same goes for other confounding variables.  Proper science consists of eliminating confounds, not just saying "eh - that probably doesn't matter." 

NOTHING can be concluded from the WARPIG study.  Had they fired an extra few hundred shots, measured every shot, and done some actual stats, then we could have made a conclusion.  But that conclusion would have been:  Using this equipment under these conditions, we found no difference between open and closed bolt operation.  Additional studies will have to be done to eliminating confounding variables and establish external validity.

We can either be scientific about it or not.  Or, of course, we can just be unscientific and pretend that we are being scientific.  That is also an option.

I repeat - the WARPIG study was a noble but amateurish attempt, and ultimately proves nothing.

(Although as noted by a previous poster, "prove" is a tricky scientific concept)