How Much Energy

[Uncle Billy]

Quote: Uncle Billy's post #33 above is an excellent summary.

Thanks, Peetza, I appreciate that. Shooting, like virtually everything else I enjoy- motorcycles, racing, flying, sailing- ultimately can be described and quantified by the science of physics.

 

[Old Grump]

Point is that no matter what the material is when it contacts another object it loses energy, there is no gain in energy from ricochets, no gain in speed when hydro-planing just the illusion. You cannot believe everything you think is obvious unless you believe stage magicians and illusionists are doing real magic. They trick your eye, sometimes real life tricks our eyes. Makes eyewitness reports interesting, everybody knows what they saw but did they?

You pick up these things with white hairs, the older you get the more you know you do not know.

 

[Frank Ettin]

The bullet begins loosing speed the instant it is no longer being accelerated by the powder charge but that actually occurs just in front of the muzzle. It has been shown that the gases that escape the barrel just after the bullet exits actually expand fast enough to add as much as several 10s of fps to the bullet.

Okay, true enough -- at least as long as the propellant charge has not been fully consumed before the bullet leaves the barrel. For some cartridges, with some propellants, at some charges, in some length barrels, the propellant may be fully consumed prior to the bullet leaving the barrel; and the bullet might then actually begin slowing down before it does leave the barrel.

In any case, even when the propellant is still burning, and the gases are still expanding, when the bullet leaves the barrel, the acceleration of the bullet drops off very quickly once the bullet leaves the barrel and the gases are free to expand in multiple directions.