Re: Sig 556 Classic Swat or Russian
If you want to do 7.62x 39 then you have a few choices. You can go AK and find one for way cheaper and it will perform most likely flawlessly (Ten million jihadist can't be wrong).
Or you could buy a Russian model SIG and have a dressed up, cool and heavier AK with a few modern twist for more $$$$.
They both will do the same thing though.
In my opinion have one good running AK in 7.62x39 just for the hell of it because it's fun and will function like a good knife (Always reliable and easy to use.)
Have a good AR-15 5.56 with a flat top upper or atleast an A4 (Armalight,Colt,Bushmaster,Stag,etc,etc,etc.)
If you are going to do three gun, go with an AR-15 although an AK will do just fine until you go beyond 200 then the AK can be hard to get on target for some.
Mounting optics on an AK is one of the drawbacks that that platform has. The AR-15's have that down and are more readily available in so many versions.
As to which caliber has more knockdown, it's arguable from both sides.
The 7.62x39 is fairly equivalent to the 30-30 winchester round. Past 200 yards they just loose alot of umph but within 200 they kill perfectly.
Bullets used these rifles has alot to do with their performance.
FMJ's cannot compare to explosive or expanding hunting rounds.
The 5.56 if moving at 2,400 fps or above has a devastating effect on fleshly objects/ballistic gelatin. Below 2,400 fps and it looses alot of it's performance.
Hang around on this site and read a lot and access the search funtion and you will find out many answers to your questions.
Until then have fun.
....SmokeRolls