The Iver Johnson 1911 Mainspring Housing, .45 ACP, Black Steel, Flat (brand part number IJ1911MSH) is a replacement mainspring housing for 1911 pistols chambered in .45 ACP. Built by Iver Johnson, it uses a flat-style profile with vertical serrations cut into a black oxide steel finish for a secure, non-slip grip at the base of the frame. It fits Government, Commander, and Officer size 1911 frames, though some fitting may be required for a proper drop-in installation. Internal parts such as the spring and plunger are not included and should be reused or sourced separately.

Key Specifications

• Fits 1911 pistols chambered in .45 ACP.
• Flat-style mainspring housing design.
• Finished in black oxide steel.
• Cut with vertical serrations for a secure grip.
• Fits Government, Commander, and Officer size 1911 frames.
• Some fitting may be required for a proper drop-in fit.
• Does not include internal parts such as the spring and plunger.

Frequently Asked Questions

What 1911 frames does this fit? Government, Commander, and Officer size frames.

Are internal parts included? No, internal parts such as the spring and plunger are not included.

Buy the Iver Johnson 1911 Mainspring Housing, .45 ACP, Black Steel, Flat

Refresh your 1911’s grip with a part from our gun parts and accessories selection. Order it from our Lubbock, Texas gun shop for fast, insured shipping.