The AK74 is an updated version of the AK47, it uses a slightly smaller round and with the addition of a muzzle break it reduces the recoil of the weapon. The exact specifics I can't recall at this time, but it is also more accurate than the AK47.
The best part is that ammunition (If you use the steel cored stuff, which can't be used at indoor ranges) is stupidly inexpensive.
You can get 1080 rounds for a little over $140
http://www.aimsurplus.com/product.aspx?item=A54539R&name=Russian+5.45x39+53grn+FMJ+1080rd+Can&groupid=33
as opposed to 1000 rounds of 7.62x39 that the AK47 uses for $239.50 at AIM surplus
http://www.aimsurplus.com/product.aspx?item=ABS76239HP&name=Silver+Bear+7.62x39+HP+123grn+20rd+Box&groupid=39
or $218.00 at SGAmmo.com
http://www.sgammo.com/product/brown-bear/500rd-762x39-brown-bear-soft-point-poly-coated
Yeah, AK47 ammunition is getting more and more expensive as the military surplus stuff starts to dry up.
Oh, and by the way, if you're looking at a WASR-10, best to get it from Henderson Defense where they're "Certified" meaning they go through a thorough inspection to make sure they are clear to go. That way you don't get a lemon (Which WASR-10's are known for) with canted sights and all sorts of headache inducing problems usually associated with the cheap AK47/74's which almost all are imported by Century Arms International.
