A tale of two screws

It was the best of times, it was the worst of times…

Yesterday, I finally dragged my 625 which had been recently upgraded with a Bowen Rough Country rear sight and a Wolff Reduced Power mainspring out to the range to function test and sight in, as well as maybe do some practice.  After installing the reduced power mainspring on the 625, the trigger pull was down to about 7.5 pounds, which I thought was odd – both of my Pro Series revolvers come from the factory with reduced power mainsprings and their trigger pulls aren’t nearly that low.  But I didn’t think too much of it…until I got to the range.

First round, a Magtech 230 grain FMJ goes “click” instead of bang.  I look at the primer, and there’s a dimple on it, not a really good hit.  Okay, well Magtech has hard primers I think, I’ll try the Remington ball ammo that has softer primers.  That I get 4 clicks and 2 bangs in one cylinder.  So next I switch to my Federal 230 grain FMJ, which has the softest primers of all.  3 clicks, and 3 bangs.  By this time, I’m getting angry, and I’m worried because I think I might have screwed up my gun somehow when I installed the new mainspring.

So, I tear into the gun.  Grips come off, and I check the strain screw to make sure it’s bottomed out.  It is.  As I’m looking at the strain screw though, I get the feeling that something isn’t right.  So, I open up my 627 (the 8 shot .357) on a hunch to have a look and inside.  The strain screw looks longer on the 627, but it’s hard to tell when it’s installed, so I pull the screws on both guns and look at them side by side.  Sure as shooting, the screw on the 625 was a good millimeter or two shorter than the screw from the 627.  Upon closer inspection, the 625’s screw had clearly been dremeled down by the previous owner of the gun.  I had bought the 625 used for a steal, and hadn’t inquired if the prior owner had screwed (hahaha) around with his gun in any way.

It seems that to get a lighter trigger pull, the previous owner had simple ground off the tip of the strain screw to ease the tension on the main spring.  After I was done cursing his name, his children, his children’s children, and the inventor of the bloody dremel tool, I installed the standard length strain screw on my 625 with the reduced power mainspring and the gun once again runs like a top.  The trigger pull is about 10 pounds now, but it’s very smooth thanks to the new spring.

Meanwhile, my 627 has the old mainspring from my 625 in it with the short screw – I am getting really good at pulling the side plate off that gun.  The moral of the story is that if you’re buying a used revolver, especially one that’s been used for competition, it would behoove you to ask the previous owner if they modified any of the parts in a way that can only be repaired by buying a new part.  It’s times like these that I want to toss these revolvers, buy an M&P in .40 S&W and just shoot Limited-10 and Enhanced Service Pistol.  It would be nice to have a competition ready gun out of the box for once…


  1. Sure, the grass is greener, but I really do enjoy shooting revolvers. It’s a much more spiritual activity than shooting a semi-automatic.

  2. As one who has only occasionally opened up a revolver (and never an S&W), I’d appreciate it if you could post some pics of the aforementioned springs and strain screws.


  3. When I tweaked my 625 I bought a couple of extra strain screws with the springs. Once I was sure everything worked as it should after the spring swap I dug out the fine micro file and the micrometer and started taking about .010″-.015″ off the screw at a time. At about the .060″ point I started getting a few random clicks instead of bangs. I took a spare screw, measured it, and made it .030″ longer than the “test” one. It was worth about 1/4-3/8 pound of pull, and the gun hasn’t misfired in two years and a bunch of matches. And, there’s one more unmodified screw in the range bag, just in case.

    One thing you might try – using 1000 grit paper, very slightly round and polish the end of the strain screw, and put a tiny spot of moly grease on the end of the screw. The spring does move against the screw slightly during cycling and that seems to help it stay smooth.

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