I realize this post has some age but it is very relative to my recent issue with a 550-1. Hope you don't mind my resurrecting it.
So, I had the bright idea to dabble in a "restoration project". Something I've always wanted to do as a hobby. I found an old 550-1 in my step-dad's safe that looked like a prime suspect. The stock was a mess, the metal had rust; all in all it had it's best days behind it, so I figured I couldn't hurt it. I got my step dad's blessing and carried it home.
I have the stock back to something I'm proud of with a Tru-Oil finish. I originally planned on a re-blue but did some reading and discovered a little turpentine and 0000 steel wool made all the difference. A couple of nearly unnoticeable stains remain, but heck it gives it character
I've given it a good soaking in Diesel fuel, cleaned the action and have the bore shining like a new dime! It really did clean up nice, it was REALLY caked up before hand!
I disassembled the receiver by unscrewing the receiver plug, removing the spring, bolt handle and bolt. I also removed the safety, sear cup and spring described in the previous posts. Ooops? The sear cup head had been previously mangled by an attempt to over tighten or by using an improper size screwdriver, but it seams to thread fine.
I'm not sure if I have a problem or not. When I drop the sear spring into the sear indent and place the sear cup over it, I can push against the spring tension and thread the sear cup into the receiver. I thread until it's tight but notice the trigger seams tight until I back the sear cup off a bit. Once I do this, the trigger gets some "bounce" back as opposed to being almost stationary.
Figuring I had a problem, I attempted to follow the directions in the previous post by further removing the trigger. I drove the smaller front pin out, no problem. The larger trigger pin will not budge! Bent my brass punch trying! I tried to drive it out both sides of the receiver, no luck. Pretty sure it drives out left to right?
So, my question is; by removing the sear cup and spring, did I cause this issue described that so many 550's have? Since the sear cup threads seem undamaged and I can tighten it without cross threading, am I okay? (Note the cup does not seat tight against the receiver when tight, there is a slight gap where it does not thread all the way flush). Do I still need to remove the trigger and go through the steps listed in the earlier post? If so, is there a trick to getting the trigger pin out?
Also, before I realized I may have an issue in this area, I attempted to reinstall the safety, but am having a bugger of a time with getting the trigger spring/plunger and safety in place. Is there a trick to this also, or am i just not holding my tongue right ; )
You guys are right, this is a bugger of a gun to tinker with......just my luck on a first project! I really don't want to have to throw this thing in a box and walk into the gunsmith with my story of woe. With the TLC I've given this ole girl so far, if/when I get it back together I think it will be an excellent shooter and not bad to look at! Hope you can help!