replacing MIM parts on SA 1911 (questions)

[brickboy240]

I really want to replace the MIM parts on my stainless GI Springfield Armory 1911. So far, here is the list of MIM parts that I have to replace:

hammer
barrel bushing
mainspring housing
grip safety
ejector
extractor

Now, I do worry about breakage, but I mainly want to replace htem, because they look unsightly! They don't match the silver stainless machined parts at all. The pistol is an above average shooter and I don't necessarily want a beavertail safety or any other altered parts...I only want the same parts in machined stainless that might match up better with the slide/frame pieces. I also like an arched mainspring housing (yeah...I know...I'm wierd that way!)

Is there a company that sells exact replacement parts, that I could swap out? In know that some will have ot be fitted and I have a good 1911 smith that can do the deed. All I ma finding are the parts like Wilson, Ed Brown and all sell for competition and fancier 1911s. I am sure these are great parts, but I just want replacement parts that are stainless and machined.

Any suggestions?

Thanks!

-Brickboy240

PS: is there anything special I should know about swapping the mainspring housing? It has that wierd locking device.

 

[mattk]

Well you can probably find everything you need at Brownells.
I am not sure your list of MIM parts is correct though. I have owne several SA guns and none had a MIM Bushing or Mainspring housing or ejector.
I think the MIM parts that you should replace first would be
Sear, thumb safety, hammer and extractor.
The grip safety and Mainspring housing if MIM are actually great parts to be MIM. Very low stress on these parts.
I have guns with MIM parts never had a breakage, but i have seen a bunch. Usually on SA Sears that have had a trigger job done to them.

 

[brickboy240]

The safety on my SA 1911 sure looks like its machined steel and it matches the slide and frame exactly. So does the slide stop. I have heard of SA 1911s coming with these parts MIMed, but I really doubt mine are.

Yes, the ejector and barrel bushing are MIM. They are a wierd uniform light silver, that does not hanve any grain to it and no machining marks and they don't match the slide/frame at all. They are, however, the same shade of silver as the other parts I mentioned.

I would guess that a MIM extractor and barrel bushing are things you don't want anyways, but they simply look terrible. Couple that with the stress they'll go under and I might as well replace them.

So...the sear is MIM in these pistols, too? Well then, I'll be swapping that as well.

(why is it that all the makers are "cheaping out" their pistols with this crap? I have seen Colt and Kimbers with this crap too. If I had payed that much...there BETTER NOT be any MIM parts on the damned thing!)

-Brickboy240

 

[R.H. Lee]

How about the disconnector? Is that MIM also?

 

[ABBOBERG]

I was told (by a MIM manuafacturer) that MIM parts can be heat-treated to the same strength as the wrought version of the material. He gave me a sample part that looks like an extractor from some type of automatic rifle, and it looks and feels great (if you don't mind the random texture). It's about 2-1/2" long, and the "spring" is built-in. I bent it quite far, by hand, and it snapped right back, which implies they achieved a spring-steel type yield strength. It is entirely possibly that the parts you identified, if they were properly heat-treated would hold up fine - all you would need to do is some hand-polishing.

 

[R.H. Lee]

Heat treated how? To what temperature? Allowed to slowly cool, or quenched in water?

Anyone interested in doing a test or study on this?

 

[ABBOBERG]

I actually got a specification for the heat-treatment of 17-4 SS, which is fairly common in US made guns. I don't have the specification with me, but it involved heating the part up to a certain temparature (like 1400 F), quenching it (oil or water?) and then a "solution treatment" at a certain temperature to anneal the part to the desired hardness and strength. I recall that an average gun part, like a hammer or trigger, will cost 2-3 dollars with holes reamed and heat treatment. Although the tooling cost will average around 8 grand per part, you can see why manufacturers are switching to MIM parts, because if they have the sales volume, the tooling costs are insignificant. I see small MIM parts selling in Brownell's for 30-40 bucks!

 

[Berg01]

EGW

Hey, do yourself a favor; send your gun to these guys c/o George Smith. Ask for the Tactical Carry Package; 3-4 months & $400.00 later you'll have a 1911 that you could only dream about beforehand.

By my estimation , in your post, you spec'd out about $240.00 in parts alone; unless you are a Master Pistolsmith (and you probably are not), your results will not come anywhere near what EGW does for its customers (myself included) on a routine basis.

 

[Shalako]

MIM slide stop?

How about the slide stop? When I took my c.1999 SA Loaded Stainless into the gunsmith for a trigger job he was not at all impressed with the slide stop. I don't know if it was MIM but he said it was slightly smaller than the frame hole so it could eventually oblong the hole. We ordered the tool steel one from Wilson. Also got a new sear, wilson 30 lpi MSH, and all new pins and springs.

The gunsmith seemed ok with the hammer, extractor, and ejector. [shrug]

I guess he also didn't like my two-piece barrel, sharp edges, or vertical slide/frame fit and truley hated my houge wrap-arounds. [shrug^2]

Oh well, I probably didn't need all that cash anyway.