Given equal loads and equal charges of black powder, there is an immediate and obvious difference in pressures due to the gas loss that escapes from the flintlock vent or percussion nipple. In the case of flintlocks, the size of the vent is critical because going too large in order to get more reliable ignition also causes a corresponding reduction in chamber pressure that lowers velocity.

Voting for anti-gun Democrats is dumber than giving treats to a dog that shits on a Persian Rug