I dont see an issue as BBs are not that expensive and its not a regular occurrence.. I once emptied out my mags into someone elses mag as I had no lives left and it was the last push before a trip back to the safe zone, so allowing someone else a chance to finish seemed no big deal for me.
I run out once, my M4 was down and my pistol mag PFFFFT out of gas, so rather than go back someone lent me their pistol to use B) I was very surprised, he didnt seem to think anything of it.
I run out once, my M4 was down and my pistol mag PFFFFT out of gas, so rather than go back someone lent me their pistol to use B) I was very surprised, he didnt seem to think anything of it.