Sorry. I guess I should've said the pin would be "bowed" across the raised ridge of the spring when it was installed. I thought my description in post #5 made it clear the raised ridge on the sear spring lifted the pin as it passed over it, and that would require the pin's advancing end to be pressed forward/downward (depending on your perspective) to be able to align it with the opposite frame hole.
Just out of curiosity, was the sear leaf spring broken side-to-side or lengthwise?
The sear leaf spring I replaced in my own 403TSW was because I tried to adjust the original spring's positioning, which had developed some unexpected and undesirable looseness. It could slip downward in the frame, as the bent tab at the bottom of the spring could move lower within the frame hole.
I'll relate one of the embarrassing lessons I learned many years ago, as a younger armorer.
Back in those days (15 years ago?) I was explaining my concern about the somewhat loose sear spring in my 4013 to a more experienced S&W armorer. He explained that there was a method to put more pressure on the spring. He said that the middle of the sear pin could be "adjusted" to press it closer against the sear spring. Yep, that involved a bit of old fashioned whacking with a stout punch and a babbitt bar. He also said that it was sometimes possible to apply too much pressure against the spring, which might risk creating a difficult-to-see partial lengthwise crack in the spring.
Rather than take simple route and just order a new sear pin and spring, I tried to follow his directions and "adjust" the sear pin. Well, it worked. Sort of.
The pin acquired a nice (and noticeable) deflection downward against the spring, and the spring definitely wouldn't move anymore. Now, instead of being bowed across the spring, the pin was flat, but no longer exactly straight, either. It was kinda "flat" in the middle.
The other armorer's words about the possibility of creating a difficult-to-see crack niggled at the corner of my mind. he said that if a crack had occurred, it would likely eventually become visible ... when the spring broke further apart (meaning now visibly) and caused functioning problems. Sigh.
So, I'd sort of thrust myself into one of those armorer lessons that falls into the category of
fixing something that wasn't really broken. Sure, the spring was loose and the top of it
barely engaged the sear, to a minimal degree, and it bugged me, but it hadn't exhibited any actual functioning problems.
The deflection and weird kink I'd caused to the pin made me wonder if I'd be able to remove it from the aluminum frame without having to cut it, or end up damaging the frame. So, I stored the fully disassembled 4013TSW away in the safe for a while, annoyed with myself for having tried to adjust something that was probably best corrected by replacing parts. I had plenty of other 3rd gen's, and was given my pick of different ones to carry for work, so I could afford to ignore that 4013TSW for a while (meaning until I either got over my embarrassment and decided to just fix it myself ... or arranged to send it off to the factory and let them use their fixture/jig to install a new sear pin over a new spring).
One day I ordered a couple of new double stack frame sear pins, and put them in one of my parts bins. (I didn't have any because they were reported to so seldom break, and I'd never seen another one break out of the thousand-odd guns I'd helped maintain.)
Then, one day a couple years later I finally got out the parts and the stripped 4013TSW frame and decided it was time to either fix it myself, or confirm that I really needed to send it back to the factory and ask for help resolving a dumb armorer screw-up.
Surprisingly, while I was half expecting the no-longer-straight sear pin to not come far enough out of one side of the frame to let me remove it, I was able to drift it out one direction far enough to let me then move it the opposite direction and lift it clear of the frame. The bent/tweaked part never had to enter either side of the frame. It came out so easily I was both relieved and embarrassed (that I'd waited so long to do it).
Next came the installation of the new spring and pin.
Fortunately, I'd thought about how one of the armorer instructors and that other senior armorer had explained gently deflecting the leading end of a new pin across the raised ridge, whether by fixture equipment or by hand, and had a couple methods in mind to try.
Well, as it turned out, once I stabilized the frame (to free both hands) I was able to exert careful and slow pressure against the leading end of the pin, pressing it downward and to where it would align with the opposite frame hole ... and damned if pressure against the other end of the pin, at the same time I was applying pressure against the leading end of the pin, didn't result in the pin simply going into the hole. On the first try.
I'd even managed to keep the spring properly positioned. It was anticlimactic.
My next thoughts were, "That was too easy.", and then, "
Now what the hell did I do wrong?!?"
When I finally accepted that it had gone as it was supposed to have gone, and a little forethought and preparation had paid off .... and I
was an armorer of some little experience, after all, even if I'd never had to replace a sear spring ...
then I kicked myself for having postponed making this repair for a few years.
I assembled the gun, lubed it up and loaded some magazines, and then set it aside in the safe for my next range trip. It ran like a top. I remembered why I'd liked it so much.
I remembered why there were some senior guys at work who were longtime shooting enthusiasts who had been on a list to have one of the then-new (mid 2000's) 4013TSW compacts issued to them, as they trickled in. I'd gotten one back then because of my position as an instructor/armorer, and because my primary assignment was a plainclothes one, and justified me having one.
I used it as my duty weapon when I was sent off to an instructor update class, which involved a lot of shooting for score, including out to 50yds. I also used it to run through our 10-100yds patrol
rifle course of fire, and scored a qualifying score (90%) with it, just to show that it could be done. (It was also fun to see the sidelong glances from the guys shooting the qual line with their AR's, seeing me shooting alongside them with a compact pistol. You've gotta get your kicks where you can.
)
I eventually arranged to trade it off and have it issued to one of the command staff who really, really wanted one. I took his 4513TSW compact in exchange, which I carried until my retirement.
Thanks for letting us know how it went. (Don't hesitate to take it by a local gunsmith to let him check it out if you wonder about your repair.)