They redirect some of the gas from the barrel to help offset muzzle flip and recoil.

PanaDP is on the money. They reduce muzzle jump. They're fine for recreational guns but have no place on fighting pistols.

Originally Posted by Mike Barham

They're fine for recreational guns but have no place on fighting pistols.

Legal reasons?

No, practical reasons. If you have to make a contact-distance shot from a tucked in retention position, the ports will vent hot gas and powder particles directly into your face and eyes. Fighting blind is not ideal.

Originally Posted by Mike Barham

PanaDP is on the money. They reduce muzzle jump. They're fine for recreational guns but have no place on fighting pistols.

Please explain. I'm looking at a Glock 19c, compensated and have read that for a 9mm, a compensated/ported barrel won't make much difference. Does it also create other problems?

Originally Posted by Dsig1

Please explain. I'm looking at a Glock 19c, compensated and have read that for a 9mm, a compensated/ported barrel won't make much difference. Does it also create other problems?

It may not be as spectacular as a .454 casull or a .500 S&W with a ported barrel, but I would rather keep the bad stuff flying at a bg rather than in my own face.

Originally Posted by Dsig1

Please explain. I'm looking at a Glock 19c, compensated and have read that for a 9mm, a compensated/ported barrel won't make much difference. Does it also create other problems?

See my post above regarding defensive use. I would never bother with porting a 9mm, which has very light recoil to begin with, unless I was shooting seriously in speed-oriented competition (IPSC, Steel Challenge, etc.).