All it takes is an experienced player to differentiate...it's sorta like when the Garand goes "ping!". You're sorta telling the other guy - hey I'm outta ammo for my primary! :P
Although in your case if you're not looking, you shouldn't be firing the gun at anywhere...
Scarecrow - "old geezers like myself and Starlight"
- "senility prevents me from recognizing anyone except people who owe me money.."
Greylocks - "The heck with 'getting'. I am old."
SF - "Neal! You are the one!"