BudsGunShop.com - Sig 1911

It will fit and work fine as a "range " magazine but will extend below the grip so without something like the X grip spacer I would not use it for carry/defense midwayusa.com/product/1006118010/x-grip-magazine-adapter-1911-government-magazine-to-fit-1911-officer-polymer-black

Stay away from magazines that are too long for the gun in a 1911 because during slide lock reloads they may become over-inserted and tie up the gun and need to be tapped out with a dowel. Stick with the proper length magazines.

Peter, it will function but will extend slightly as it is a Full Size 1911 Magazine. The "Officers Model 1911 Magazine" will fit perfect : budsgunshop.com/catalog/product_info.php/products_id/74364/Sig+Sauer+MAG1911457+1911+45+Automatic+Colt+Pistol+%28ACP%29+7+r