So, is this the famous Phased Plasma Rifle from the Terminator?

[JDub1]

I was watching the Terminator the other day, and the flashback scene had another Terminator with a massive gun, and I wondered if that was the gun Arnold was talking about in the ammo store scene?!? Franco Columbo (God rest his soul) in the flashback scene as the T-800 had an impressive looking gun! Even Bill Paxton's character in Aliens mentions they have one, but we never see it.