While I’m not an expert on what type or brand of 6mm bb’s you should use I do want to recommend this brand. Now you know when you purchase various airsoft guns sometimes included is a small pack of sample bb’s. Usually these are about the cheapest and worst sample packs out there are but of course there is a reason for that. I never had too many problems with ammo until I acquired an electric m4 by Elite Force. It worked fine with these Crosman brand bb’s and then I found some that were cheaper so I thought I’d try them. What the hell, less money for more? Yeah well the rifle would fire about 10 or 12 rounds then jam, over and over. Then I read on YouTube I think that this brand of electric rifle is somewhat finicky about what is fired through it. But as long as I use these bb’s and don’t over load the magazine, it fires quite well. In the near future I’ll have a review of the m4 I’m speaking of and the accessories I’ve added to it. Yes, an m4 needs a scope, a  sling , picatinny rails………………