Originally Posted by Spitlebug
Any rapid deformation of 1.3mm or more will likely cause the paintball to break. Jack's loading fracture videos show the balls deforming at comparatively slower speed than that experienced after the firing cycle.
First, do not confuse acceleration with speed nor force with pressure. Velocity is not a good indication of stress experienced by the ball.
Balls are stressed more during the loading cycle than firing cycle.
During the firing cycle gas pressure is spread over the entire back ball surface evenly compressing the ball. It does not 'kink' the outer surface as does ball on ball action. It does not press a narrow band into the ball as does ball on breech.
During the loading cycle they experience massive localized pressure and deceleration (negative acceleration). If the loader forces two ball surfaces of roughly 0.0025 square inches together with one pound of force, this equates to 400psi. That is significantly larger than any pressure experienced during the firing cycle.
Additionally do not think the peak force acting on the stack is hopper force alone. Ball momentum can be significant... and likely the main cause of all loader failures in Jack's videos.
Simon's recent comments on their new loader (MCB) are very enlightening.
If the ball decelerates from 5fps to zero in 0.5mm that's an order of magnitude greater acceleration then anything the ball experiences during the firing cycle.
Second, Poe's statement was in regards to deflection 1,3mm or lower not greater
. Brazy is asking about a 6mil gap closing due to the pressure. Do you think any of the videos can show a 6 or even 60 mil change
I would love to hear ideas on how to test this. How about increasing pressure behind the ball while countering the force via centripetal force. A light behind the ball would show any change in shape since the reflections of the barrel exaggerate any gaps.