Manufactures never state "How Far" a pellet will travel. They just say several thousand yards or something like that to cover themselves. It really depends on the power plant in the air gun and the weight of the pellet. (YES pellets come in different weights) obviously a lightweight pellet will travel farther than a heavy pellet. But a Heavy pellet will fly straighter and have more knock down impact than a lightweight pellet.
Wind, altitude and angle all have an effect on length of shot.
Colt makes a 1911-A1 Pellet gun made by Umarex. I know of no BB gun unless you are asking about an Air Soft gun. The Pellet gun is very good. I can not answer about an Air soft gun.
Colt 1911-A1
Colt 1911
The Colt 1911 A1 is rated at 395 FPS (Feet Per Second)
1924
Colt 1911 defender
Colt 1911 .45 cal
Mind you that "Colt" is not just the name of the gun, it is also the manufacturer of it, too.
You will have to call Colt to find out.
Blue Book of Gun Values
You can not expect an answer when you did not provide the serial number. The Blue Book of Gun Values has sn data or you can call Colt.
Can not be answered without knowing how heavy the pellet is, how fast it will be leaving the muzzle, pellet shape, location where it will be shot.