just reading a little about the cossack uprising against poland in the 17th century.anything close in 1/72 to what these guys would look like,light mongol types maybe?

Orion and Zvezda does some 17th century cossacks in 1/72.

Look here: http://www.plasticsoldierreview.com/PeriodList.aspx?period=14

the orion cossack cavalry is one of the best sets they have done.but i was wondering what could be used for the tatars.i know mars is bringing out a set.

Sorry! I just saw "Cossack uprising" in your post and missed the subject title about tatars!
I thought the same way as you and bought Italeri's first Mongol set (i.e not their new second set) to get the light cavalry figures.
HÄT are soon to release a set of Huns that looks promising.

the hat set does look promising.i see mars released a set of these recently.but judging by their first set,im not so sure about them.