What does a r in ar15 stand for?

How do you shoot sears roebuck BB rifle Ware do BBs load at? Can the sa 08 weatherby shoot a slug? What is the value of Stevens model 887? When was your springfield 12 gauge serial 71809 central arms co and Stevens arms co and chicopee falls mass is on the gun too -94a- and 71809 21 are the numbers on the gun made? When was my colt official police 22 long rifle made and what is it worth? How To assemble 760 crosman? What is the purpose of air ejector? How do i contact the batf? Which technique of carrying a firearm should you use when you need to fire quickly? How do you take apart a cobra 380 cal semi automatic? Does venus god have a weapon? What year was the Remington 30 cal pump rifle made? How can you tell the age of your Colt 38 Police Special serial 871803? Where can you find a list of rifles from the smallest caliber to the largest caliber? Who manfactures Winchester guns? What is the value of a John M Smyth Co Faultless Goose Gun shotgun with bc545 stamped by the trigger guard? How can you tell if a Montgomery Ward Hercules 12 gauge shotgun was made by Iver Johnson or J Stevens? What is the value of a Winchester 33 WCF? When was your Winchester model 67 made? What is the back part of a gun called?