Reduced Main/Hammer Spring

[Talin342]

I'm probably going to purchase an Advantage Arms .22 conversion kit for my Springfield GI.45 Champion. However, I am a little wary of their recommendation to exchange the original mainspring for one with reduced power (23# vs. 18#). (Their website actually refers to the mainspring as a hammer spring).

I've reviewed the procedure to change out the mainspring, and it doesn't look too difficult. However, I don't want to take disassemble the mainspring housing everytime that I swap the .45 for the .22 and vice versa.

Two related questions:

1. How would an 18# mainspring affect the function of the firearm when firing .45 loads?

2. Aside from Advanatage's statement about reliability, does anyone have any practical experience using the original mainspring with the conversion?

Per AA:

Our newest 1911 kits work pretty good with the factory 23 pound spring. Using an 18 pound spring with 45 rounds does not affect the gun. Most serious shooters switch over to the 18 pound spring in their 45's.

Does anyone know if the above statement holds water?

Thanks!

 

[451 Detonics]

Considering you can get a Colt mainspring housing for 8 buck, and the other parts for it for just a few more dollars, I think I would just set up another mainspring housing to use with the conversion.

 

[Winkman822]

I'm probably going to purchase an Advantage Arms .22 conversion kit for my Springfield GI.45 Champion. However, I am a little wary of their recommendation to exchange the original mainspring for one with reduced power (23# vs. 18#). (Their website actually refers to the mainspring as a hammer spring).

I've reviewed the procedure to change out the mainspring, and it doesn't look too difficult. However, I don't want to take disassemble the mainspring housing everytime that I swap the .45 for the .22 and vice versa.

Two related questions:

1. How would an 18# mainspring affect the function of the firearm when firing .45 loads?

2. Aside from Advanatage's statement about reliability, does anyone have any practical experience using the original mainspring with the conversion?

Per AA:


Does anyone know if the above statement holds water?

Thanks!

It will not adversely affect a .45 ACP to replace a standard 23# mainspring with a 18# or 19# spring. Doing this will ever so slightly lighten trigger pull, ejection will improve, and it will be easier to hand cock the hammer.

FWIW, Wilson Combat uses a 19# mainspring standard in their full size 1911s as opposed to the more common 23# spring found in Colts, Kimbers, Springfields, Smith and Wesson's etc.

 

[Jim Watson]

I have never had a misfire with a 19 lb mainspring in a 1911 pattern gun.
Some say it affects the cycling of the action but not to where I can tell.

NOTE: If your Springfield has the ILS key lock mainspring housing, its internals are different.
You can either put in a 24 lb spring to replace the factory 28-30 or you can put on a standard mainspring housing without lock and with standard length spring of any rating desired.

 

[Quack]

it's not a problem, i use Ed Brown 19# springs in my guns.

FWIW, the SA MS with the ILS is 28#.

The ILS uses a shorter spring and a larger MS cap and no pin.
if you replace the MS, you will also have to replace the MS cap and cap pin with the new MS.

 

[9mmepiphany]

Like everyone else, I haven't had any problems with a lighter mainspring.

If you are really worried, the easiest route is to just have two MSH assemblies and switch them out when you switch the top ends