Posted By James C Chandler Jr
Most of the Sig 556 rifles appear to be 16" barrel (with some longer barrels available). The Sig 556 pistol has the 10" barrel and slighly shorter fore-grip.
Hard to tell perfectly from the pictures, but the pistol's 'pistol grip' seems to be shaped a little different than the rifle's pistol grip, but not radically different.
The shape of the pistol's receiver looks very similar to the rifle's. In fact, where a collapsible stock attaches to a round port on the rifle, is what appears to be an identical round-shaped fixture on the pistol.
So is the rear fixture on the pistol functional, just filled with a plug? If one wanted the option of turning the Sig 556 pistol into a very short rifle, could one just attach a sig collapsible stock? Is it just a matter of twisting a few screws, or is it more complicated?
Similarly, how difficult is it to remove the collapsible stock from a sig 556 rifle, and would that somehow break any laws? Gun law is so 'non-intuitive'. Admittedly a 16-inch barrel pistol might be too front-heavy and cumbersome, but if one had a sig 556 rifle and wanted to experiment with it as a pistol, would that be an easy option?
Have never dissasembled an AR-15 type firearm. Is it a quick job, or a frustrating techie job, to swap barrels?
Guess you can see where this line of questioning goes. I like tinkertoy gadgets, and was wondering how idiotic it might be to get a few spare parts and have the option of either rifle or pistol, depending on one's whim?