After battling with the strain screw in my 625 and finding out it had been ground down by the previous owner of the gun, I had gone ahead and installed the strain screw from my 8 shot S&W 627 in the .45 ACP 625, which then gave the 625 a smooth 10 pound trigger pull that lights all the primers I can find. However, the 627 was stuck with the shortened strain screw which didn’t put enough tension on the mainspring to light factory ammo reliably. Last night, I received more parts from Brownells to continue the project – I ordered a Wilson Combat Mainspring, and two replacement strain screws to get the gun going.
After installing the Wilson Combat mainspring with the shortened strain screw, I noticed that at times I would experience knuckling, where the revolver would bind due to the strain screw not being long enough. So I took the Wilson mainspring out and replaced it with the Wolff Power Rib spring and the replacement full length strain screw. After getting everything installed, the trigger pull on the 627 is now right around 9lbs, which should be sufficient to light primers with everything installed correctly. I’m going to head out to the range today and test it on a batch of Remington UMC 130 grain ball ammo.
I hope it works. I’m tired of screwing around inside these guns, especially since last night I slipped with the screwdriver while putting the sideplate back on and managed to scratch the side of my gun. That’s more of an annoyance than anything, since competition guns tend to get pretty beat up anyway; but they’re supposed to get beat up from shooting, not from me constantly taking the sideplate on and off!