Both the SKS-44 and the AK-47 fire the 7.62x39 cartridge.
SKS-M and SKS-D
7.62x39..same as SKS and other soviet block small arms
The SKS and AK-47 saw their "FIRST" full scale action against US Forces during the Vietnam War; 1961 thru 1973. In Vietnam, SKS's were replaced by the AK-47 by 1969. If the SKS was built prior to 1973 and has a US Government tag accompanying it as a "War Souvenir" then it is a "battlefield pick-up." All GI's bringing SKS rifles or K-54 pistols back from Vietnam had to have a tag on them. AK-47's could NOT be brought home as war souvenirs. Since the Vietnam War, the SKS's, AK-47's, etc. have been used by nearly every nation on earth and are common in the US. If the SKS in question is not a "Viet War Souvenir" then it will be difficult to trace it's combat history.
As originally designed, no. There were two models of the SKS made in China that were made to use AK type magazines, but most SKS carbines are meant to use a fixed 10 round magazine. Many people have attempted to modify an SKS to accept Ak magazines, with indifferent success. It requires reworking wood and metal.
AK-47 and SKS for NVA and VC M-16 for USA
AK-47, Mosin-Nagant, SKS, some Dragunovs, the M14 and the M1 Garand are a few
I have a Norinco SKS-M with "blonde" Monte Carlo stock and 16 inch paratrooper barrel with bayonet lug but no bayonet. For a lightly used model in very good condition and with a 30 round ak mag and Vexor flashhider I paid $550 in January 2009. I'm glad to have it. The gun will last forever.
SKS receivers are milled. AK receivers can be stamped or milled.
You are probably referring to the bayonet lug on the bottom of the front of the barrel. It is for mounting a bayonet.
All of the fixed ten round mags are cross compatible, but cannot be used in the SKS-M or SKS-D, both of which use a detachable AK magazine.
The "47" in "AK-47", refers to the weapons date of Patton (1947).