Bullet Weight Explanation – in layman’s terms
People ask us all the time, “what is the difference between a lighter bullet and a heavier bullet in the same caliber?”
Well, in the case of pistol bullets usually the heavier the bullet the softer the felt recoil. This is because for any given gunpowder it takes more gunpowder to build the pressure required to move the lighter bullet out of the case and down the barrel than it does the heavier bullet. The “science” is a little more complicated but suffice it to say the heavier the bullet the less recoil you will feel in your hand and typically the less the muzzle will flip or rise. The tradeoff is that a heavier bullet moving slower (heavier bullets will always move slower than lighter ones) is going to drop more over a given distance than the lighter bullet. At USPSA, IDPA or 3-Gun pistol distances the lighter recoil of the heavier bullet is more beneficial than the flatter bullet path as we rarely shoot pistol targets past 30 or 40 yards. One caveat is that some firearms do not function well with the heavier, lower recoil bullets without some modification to the firearm, the new Gen5 GLOCK is one of these.
When looking at rifle bullets, usually the heavier the bullet the longer it is which means the better the ballistic coefficient of the bullet (the BC). Generally speaking a better or higher BC means the bullet will resist external forces better and travel along a straighter path. Again the science is more complicated and there are exceptions to this rule. The other advantage to a heavier rifle bullet is that it releases more energy on a target than a lighter bullet. A great example is shooting a 500 yard target in 3-gun that does not have any fancy electronic flashers; use a 55gr 223 and the RO has to be looking at the correct target and looking very closely as there is far less movement of the target when hitting it with a 55gr bullet vs a 75gr bullet.