Originally Posted by maestro
This is not totally true. The desired is to exit the barrel close to a node but when the muzzle is still rotating upwards. This will result an automated correction: pellets with higher velocity fly out a little earlier, when the barrel still aims a very little lower. And slower pellets fly out later when the muzzle points a bit more upwards, compensating their less velocity. Worth reading: http://www.geoffrey-kolbe.com/articl...g_a_barrel.htm
This does work for small/big bore rifles, but I'm not really convinced that barrel harmonics would have any noticeable effect on an air rifle. I had been using my rifle with a lot of different barrel weights, air strippers and didn't really experience change in grouping.
point i am trying to make, is that at tdc/bdc the barrel is stationary, any where inbetween these two points the barrel is moving. simmilar to a piston in an engine, at bdc the speed of the piston is 0 fps it accelarates upward reaching max velocity at the half way point in its stroke, then it decelarates intill at tdc it is at 0fps. so by the pellet exiting barrel at a node it has a better chance of grouping well. if the pellet exits at halfway between less likely to group well as speed of pellets is rarely the same.