There are a few changes. Mostly cosmetic. Metal with matte finishes , and a slimmer stock and red buttpads are about it. The new blued ones have been switched back to a gloss blue now. The new LC-6 trigger is the only real change from the MkII. Allthough the last of the MkII's have the newer trigger also. I have a few of them. Either models barreled actions will swap into either stock.