1911 curved mainspring housing?

[sprice]

How do I install a new mainspring housing on my 1911, I just got a new curved one I want to try out.

 

[rondog]

Gently tap out the pin on the bottom of the grip with a punch and small hammer, remove the old MSH, slide in the new one, re-insert pin. It's pretty easy, but the MSH may bind up a little. Use gentle persuasion and non-marring tools, like brass or wood. Be sure the hammer strut seats in the spring cup. Oh yeah, you'll have to transfer the mainspring and cup to the new MSH, but that's easy too. Just be careful and go slow, don't scar anything up, and don't drop the little pins. If I can do it, you can too.

 

[Oro]

They are commonly called "arched." So here's instructions:

Here's good instructions. Tip, if you take the hammer out FIRST, it makes releasing the MSH pin a little easier:

http://www.m1911.org/stripin1.htm


Here's the "Corinthian" way to do it without tools:

http://www.sightm1911.com/lib/tech/toolbox.htm

The only real things to be extra careful about are:

1) Don't loose the plunger spring/tip
2) Use a great deal of caution releasing the mainspring. It is very powerful and could quite literally put out an eye.
3) make sure the sear spring is installed properly with the spring tabs engaging the proper surfaces and the slot inserted. Otherwise you will get it together and it will not fire.
4) After re-assembly, run through all of the safety checks to make sure they are all functioning (thumb, grip, and the 1/2 cock notch).

If you don't have a brass punch for the pin, you can lay a small piece of thin leather over it and it will serve. You should probably take off the grips as if you don't strike it hard enough or your punch bounces, you will nick your grips.

 

[NGIB]

To prevent the sear spring from moving around, I always "tie down" the grip safety with a zip tie or large rubber band before tapping out the MSH pin...