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JOHN MASEN
1911 SERRATED MAINSPRING HOUSING

555101004

Description
Ratings (5)

Solid Steel, Serrated, OEM-Style Replacement Housings

An exact reproduction of the original factory mainspring housing, complete with vertical serrations that help improve grip but won't grab clothing. Finish-machined from a solid-steel casting; excellent for restoring or building any 1911.

SPECS: Blued (BL) or stainless steel (SS), flat (FL) or arched (AR). Fits Govt./Commander (GM) and Officers ACP (OM).

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Customer ratings for JOHN MASEN SS/AR GM MAINSPRING HOUSING

Number of ratings: 5
From brownells.com: 5
Average rating: 1.6

Poor fit at base. (16/05/2018)

The Mainspring housing fit the frame of a new colt govt with a gap at the bottom due to the mainspring housing being ground undersized leaving the sharp edges of the frame exposed to catch the heal of the hand while loading.

You Get What You Pay For - Sometimes (24/04/2015)

This thing is pretty rough and the fit is a bit off as well. The holes for the retaining pin were out of alignment and there was no way the pin was going to get through the frame. I finally had to take a carbide cutter in my Dremel to relieve the portion that was blocking the holes. So now I've got two egg shaped holes in the mainspring housing but it's secure.... I hope. Also the hole for the mainspring needs some work with a file to remove the burr around the lip. If you skip this step and just push the spring assembly in you'll play hell getting it out later. Cosmetically it's fine. My pistol is circa 1917 and this housing looks like it has been through the wars with the rest of it so it's a good match.

Buyer Beware. (07/09/2016)

Fit the frame of a Colt 1911 but the hole for the mainspring cap was undersized and it stuck a third of the way in. Would have to be drilled out to work. Pretty poor Q/C.

Overall poor quality. (26/04/2015)

Very rough finish. Does not fit flush with bottom of frame. Housing pin hole does not line up with frame holes.

Don't waste your money (26/04/2015)

The pin hole for the frame drilled off center, probably cost more to return it than it's worth, otherwise may have been okay. Live and learn, Masen and Swenson are both on my, "DO NOT BUY" list for parts of any sort.

Read 5 more ratings on brownells.com

0 0 1 GBP

Product no.: 555101004
JOHN MASEN SS/AR GM MAINSPRING HOUSING
Mfr Part: 4548AS An exact reproduction of the original factory mainspring housing, complete with vertical serrations that help improve grip but won't grab clothing. Finish-machined from a solid-steel casting; excellent for restoring or building any 1911.

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Specs: Finish: Stainless Steel Make: 1911 Model: Government, Commander

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Details

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Attributes

Finish: Stainless Steel Make: 1911 Model: Commander,Government Delivery weight: 0.054kg Shipping height: 1mm Shipping width: 76mm Shipping length: 117mm

Item details

Made in USA
US export classification: 0A501.y.1

Upgrade your 1911 with the John Masen SS/AR mainspring housing. 🛠️ Perfect fit and improved grip for your firearm restoration!

Description
Ratings (5)

Solid Steel, Serrated, OEM-Style Replacement Housings

SPECS: Blued (BL) or stainless steel (SS), flat (FL) or arched (AR). Fits Govt./Commander (GM) and Officers ACP (OM).

More...

Customer ratings for JOHN MASEN SS/AR GM MAINSPRING HOUSING

Number of ratings: 5
From brownells.com: 5
Average rating: 1.6

Poor fit at base. (16/05/2018)

You Get What You Pay For - Sometimes (24/04/2015)

Buyer Beware. (07/09/2016)

Fit the frame of a Colt 1911 but the hole for the mainspring cap was undersized and it stuck a third of the way in. Would have to be drilled out to work. Pretty poor Q/C.

Overall poor quality. (26/04/2015)

Very rough finish. Does not fit flush with bottom of frame. Housing pin hole does not line up with frame holes.

Don't waste your money (26/04/2015)

Read 5 more ratings on brownells.com

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