Questions about 1911 disassembly and replacing the MSH

[santacruzstefan]

So this was a bit of a trial by fire. I wanted to replace the MSH in the operator, and bought an Ed Brown with which to replace it (to get rid of the ILS in the Springfield). But upon removing it, it all went to ****, with the leaf spring thing getting jammed up, so I just disassembled it completely. Freeing the thumb safety was interesting; very, very tight. Everything else went ok, but I couldn't get the new MSH to work right. The first time, the grip safety quit working: I could drop the hammer with no pressure on it. So I replaced the original MSH, and also bent the far left extension of the leaf spring up a bit. This time, the safeties worked, but the hammer was lose, and wouldn't stay "down" after pulling the trigger. I ended up figuring out that I had put the little retaining pin in the MSH, and the ILS requires it being left out. So took this out, replaced it all, and now it works fine.

SO... I'm wondering what are some reasons the Ed Brown MSH wouldn't work with it (comparing them side by side, they appear dimensionally identical). Also, what could the grip safety issue have been? And is it normal for the thumb safeties to be that tight, so that I need to pry them out with a tiny flat head? Overall, I guess it was a good experience, learning how everything fits together, and at least I avoided scratching the frame with the slide stop; I was looking out for that!

[cindynles]

I replaced the ILS on my loaded with an Ed Brown Maxi-Well and it required some fitting. You will have to file it down a bit to get it to fit. I used a sharpie to see what areas of the MSH needed material removed. You also need to replace the MSH internals (cap, spring, etc) because most of the ILS parts are not compatable.

I used this Ed Brown kit from midway ($17) and it worked great: http://www.midwayusa.com/Product/126...commander-blue

[Kruzr]

As mentioned, you need to replace the MSH internals and the spring when you use the Brown MSH. Those are unique to the ILS.

The grip safety issue was most likely due to the fact that with the Brown, the grip safety sits more forward into the frame. This puts the blocking arm on top of the trigger bow. You can adjust this by the two little stops (ears) on top of the MSH. You need to take the faces back a little so the grip safety sits further out. This will drop the arm to block the trigger.

[chim-chim7]

Next time sinch down the grip safety with a tight rubber band when you remove the MSH. Everything will stay in place. The way you did it everything gets flung out.

[santacruzstefan]

Ok, so I have replaced all the internals with the Brown internals as described above. And I taped down the safety so things didn't come apart, and installed the new MSH. But again the grip safety is totally stuck. The gun functions fine otherwise, but I'm guessing its too big. Kruzr, are these two stops you mention what are causing this?

[chim-chim7]

My guess is the MSH is a little too long and is keeping the grip safety in the squezed position. Pull the MSH pin and slowly allow the MSH to creep downward and check for safety movement. Just allow it to come down about .05-.1

[Sheldon]

I will need to fit a S&A mag guide to my son's RIA 1911. The S&A mag guide is molded as part of the mainspring housing. It is just a little long and hits the bottom of the grip safety....sound like what may be going on with the OP. I just need to file the surface of the S&A mainspring that hits the bottom of the grip safety.

[Kruzr]

Ok, so I have replaced all the internals with the Brown internals as described above. And I taped down the safety so things didn't come apart, and installed the new MSH. But again the grip safety is totally stuck. The gun functions fine otherwise, but I'm guessing its too big. Kruzr, are these two stops you mention what are causing this?

Yes, it can cause that. The blocking arm is not clearing the trigger bow because there isn't enough room. If the grip safety sits just a little bit further out, the arm will have more room to move down into position. Put the two MSH's you have top to top and look at the little stops. Many of them are different thicknesses.

Here is a pic of two that you can clearly see how one had the stops thicker than the other.


I wouldn't expect your two to have that much difference but you should see one has thicker "ears" than the other.

[santacruzstefan]

Yes, it can cause that. The blocking arm is not clearing the trigger bow because there isn't enough room. If the grip safety sits just a little bit further out, the arm will have more room to move down into position. Put the two MSH's you have top to top and look at the little stops. Many of them are different thicknesses.

Here is a pic of two that you can clearly see how one had the stops thicker than the other.


I wouldn't expect your two to have that much difference but you should see one has thicker "ears" than the other.

Yep, those on the top of the new housing sat a bit higher than the stock one. Filed them down (and bent the right leaf spring up a slight bit) and now it works perfect. Thanks for you help!