Perhaps the round nose buggers fit a magazine for smoother cycles.
Then you got the tube fed rigs.
I understand the magazine thing on some cartridges, but not the -06. I know of zero tube-fed -06s.
You did not "seen" anything, you "saw" it. A "creek" has water in it, a "crick" is what you get in your neck. Liberals with guns are nothing but hypocrites.