IMO, a comp on a .45 ACP is like putting a rear spoiler on a front drive car.
The key to a comp is the speed of the bullet pasing through. The smaller calibers produce enough to make the comp very effective.
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
Life Member NRA
Life Member NAHC
Former President of the ECPT