level 5 automag? level 6.6? 7?

[Jonno06]

hello everyone.I am watching the Level 7 automag/minimag (powertube not removable).and he said the level 5 mags didnt have twist lock barrels?and the level 6.6 did?

also,what is the difference between all of the levels of mags?thanx

[LawFox32]

I am pretty sure that it is not that they didn't have twist lock it was just the the ball did not drop into the barrel, but into a chamber

[Jonno06]

yea,thats what I meant....i mean,it didnt have the breach on the barrel like they do now....does anyone know differences between levels....tom?