Forces, pressure and speed

What I love about guns is the ability of making something small into something enormous. When we compare the force that is required to squeeze the trigger, which is around 14 Newton, to pressure behind the bullet when it ignites, which is 82,7 MPa, we can see that the initial force has been enlarged. I have to add that the final force on the primer of the bullet is 104 N. This force is caused by the push of the coil inside the grip. The exponential increase of pressure has almost no relation to the striking force on the primer. It is mainly the force of the explosion behind the bullet of the propellant due to the chemical reaction with the primer.
Because of the enormous pressure behind the bullet, the bullet will exit the muzzle with a speed of 330 meter per second, which is almost equal to the speed of sound (340,29 mps).