Anything other than the plastic tip that is different than the regular 77smk?
If Hornady had made their's to fit magazine lengh... what were they thinking at the time???
The ogive is different and slightly different manufacturing. The 77gr SMK has always had good terminal performance... When it worked. The problem is like all SMK's they suffer from variability. The TMK solves that.
Are you talking the 75gr AMAX from Hornady? If so that wasn't built for or designed for AR's. At least not for magazine feeding. Remember they were designed for matches.
CBMJR,
Sierra has designed a 69gr and 77gr .224 TMK, a 125, 155, 168 and 175gr .308 cal TMK's.
