Operating Pressure vs. Barrel Length

[bjjb99]

Originally posted by ES13Raven
If peak velocity occurs early in the barrel, and decelerates a lot while still in the barrel, but the chrono reads 295fps - will it still go as far as a ball where peak velocity occurs toward the end of the barrel and the chrono reads 295fps?

Assuming the same mass for both paintballs and nothing to affect the basic ballistic trajectory, yes.

Originally posted by ES13Raven
Can the paintball hold the momentum longer?

Not without reducing drag or increasing mass.

BJJB

[Natural Newbie]

IF it's possible, making a graph of effective barrel length vs. energy would tell you the "sweet spot" (where the graphs intersect). Correct?

[Cristobal]

Originally posted by Natural Newbie
IF it's possible, making a graph of effective barrel length vs. energy would tell you the "sweet spot" (where the graphs intersect). Correct?

Sure. What you could do would be to graph effective barrel length vs. the rate of energy release. If you dump your energy quickly you'll accelerate the ball quickly and need less length, dump it slower and you'll need more barrel length.

in a sense it would be length vs. peak pressure behind the ball (for a give type of pressure release -- dependent on the valve characteristics)


In a related matter, it would be a fun deep blue excercise to calculate the theoretical amount of Work necessary to accelerate a paintball to 300fps against the force of air resistance and friction in the barrel.

The Work would give us the energy transfer, and then by dividing by the time it took to transfer that energy (time paintball is in the effective length of the barrel) we would arrive at the the average Power delivered by the marker in shooting a paintball. (Power simply being the rate of energy transfer -- how much energy that can be transfered in a given time) It would be fun trivia to know the horsepower rating your paintmarker :)

[ES13Raven]

Originally posted by Cristobal
in a sense it would be length vs. peak pressure behind the ball (for a give type of pressure release -- dependent on the valve characteristics)

I guess that is what my original question needed to be....

Some markers have fixed pressures coming out of the bolt, and have a certain "sweetspot" barrel length, but the Cocker is different because the pressure can vary depending on setup.