The recent Forgotten Weapons video about the M6 piqued my interest, especially when I looked up the catalog listing with the auction house and saw where the pre-auction estimates were and the fac that the M6 is a full-auto only gun. (Select fire guns are considered assault weapons under the Connecticut assault weapons ban) However, the same laws also (generally) prohibit greater than 10rd magazines. I know that the factory magazines are 30 rounders- which would make them a no-go. I have seen some websites marketing M6 mags as M10 magazines. Are those actually cross compatible? If so, were there any companies that made 10rd M10-compatible magazines?

I don't own any full-auto guns, but I would love to figure what some potential options might be that comply with Connecticut's laws.

The majority of select-fire guns are easily and quickly modified to full-auto only status and may then be purchased by CT residents.  The real problem, as you have discovered, is the ban on magazines with larger-than-10 capacities.  A machine gun with 10-round mags is pretty useless.

You can find M-10 (Grease Gun) 10rd mags.....

M6 mags are not compatable with anything else......not even close.....they are expensive when you can find them.....

The M6 is actually selective fire.......uses a progressive trigger like an AUG. Some were fitted with selectors however.

What he said. It's an odd arrangement, especially when you're not told before using it.

Are there no grandfathered standard capacity mags in CT? Most people own a bunch of standard AR mags. The M16 is easy to make FA only for CT.