Slide Stop

Is there a difference between 45 and 9mm slide stops?

Yes. 9mm sticks further into frame. 45 slidestop typically will not lock back slide with 9mm magazine. 9mm slidestop will interfere with 45 cartridge.
Jon

Yes, They don't exchange well either. 9 would probably work for 45 but might cause slide to lock back early. Using 45 with a 9 magazine and slide won't lock back half the time. The 9 slide stop is longer then a 45 stop where it makes contact with the follower. I measure them by holding them end to end. I will try to take picture later.

Len ( what Jon said also)

Greetings,

Colt used to stamp a number on the inside of the slide stop.

#1 = 45 ACP
#2 = 22 Ace & 38 Special National Match
#3 = 38 Super and, I believe, 9mm

Cheers,

Dave

I was taking picture while above was posted. Stop on left is 9mm. Just a little longer.