replacing Springfield Armory ILS?

[spartacus2002]

I have a Springfield Armory 1911A1 Loaded. It has the flat mainspring housing with the Integral Locking System. I want to replace it with the humped housing. Must I use an ILS housing, or can I just replace it with a non-ILS aftermarket housing?

 

[Old Fuff]

You can use a stock 1911A1 arched mainspring housing or commercial equivalent, but you should change the following internal parts too:

Mainspring cap
Mainspring cap pin
Mainspring
Mainspring retainer

The above parts fit inside of the mainspring housing (flat or arched). When they have been assembled you should be able to remove the original mainspring housing assembly and replace it with the new one.

You can obtain these parts at: www.brownells.com

 

[NoahFN]

Old Fuff has it right.

I replaced the ILS on my Springfield G.I. and it was easier than I thought. I replaced the mainspring housing all-together, as I didn't want the little lock showing in the back. I used an Ed-Brown serrated arched housing, since I like the arched feel.