This is a diagram that I made for the basic rollergun energy diagrams thread, but it will serve here for the sake of explanation, If we ignore band soak, that is stretch a band, leave it and then the force falls slightly, or dangle a weight on it and it gets slightly longer. These graphs show the energy going into the bands. It will also be an indication of the energy on the way out, but does not take into account energy losses as the bands bend around rollers, dynamic effects in the rubber, etc.

Although not to push the analogy too far you can think of a multl-band standard gun as an artillery piece, a mighty bang and the projectile gets blasted out. A rollergun is more like a rocket, the thrust is developed over a time interval and not a split second, but of course it is all relative, we cannot see it visually. You can actually see this on the graphs for a standard gun versus a rollergun. The key is the slope of the energy graph, when it is steep you have to cope with a bigger jerk, when it is shallower the jerk is less. That is all there is to it. If you want to get technical we all know F = m x a, there is a constant in there but in the units used that constant is 1.0. If we take a differential with respect to time we get dF/dt = dm/dt x da/dt. The mass m does not change with time so that then becomes dF/dt = m x da/dt. Jerk is defined as da/dt and dF/dt is the slope on those green graphs, the final ones that is. Strictly speaking the x axis on these graphs is distance not time, but the time graphs will not be too different, governed by the contraction rates. For these comparisons we assume all guns use the same bands, they are just longer or shorter to fit the gun layout. Stretch characteristics are identical.

View attachment 59537
The key take away here is short of the seven band gun ballasted to be the mass of a blacksmith's anvil no one could shoot it, but pretty well anyone could shoot the Vela, if they could afford to buy it.

The diagram first appeared here:

https://forums.deeperblue.com/threa...gy-storage-diagrams.107171/page-3#post-985014