Replace 639 hammer spring?

[Inusuit]

I want to replace the hammer spring on my 639, hoping for a better DA trigger pull. Can't find a video or instructions.

Is it as simple as driving out the pin above the lanyard loop, catching the spring and putting in the new one?

Does the pin come out left to right?

I've done the replacement on 1911. I assume this isn't rocket science, but I've screwed up a ball bearing with a toothpick.

 

[armorer951]

No nefarious secrets here....pretty simple. Remove the grip panels, drive out the "grip pin" or the pin that secures the backstrap insert. (either direction)

Remove the old mainspring. Place the new mainspring on the hammer sturrup, reposition the plunger and backstrap and insert them into the rear of the frame. Replace the grip/insert pin, replace the grip panels.

 

[Inusuit]

Got it, thank you. I was failing to move the backstrap insert backwards off the "shelf" at the base of the frame.