Light Strikes on 625

[vikingthunder]

so I bought a 625 a little while back off of here, and when I got it the trigger pull felt really really light in DA, I wasn't able to test fire it for a while because I was in the process of moving. When I was able to fire it, as expected, I got a 4 out of 6 failure to fire.

Fast forward to this week, I had a new Smith main spring and strain screw in my tool box, so I totally cleaned the gun, and installed the new spring and screw. And.... Failed to fire with light strikes 4 out of 6.


still feels WAY to light in DA, SA doesn't feel all that bad. I have several other 625's, and I have tried the moon clips and same boxes of ammo in them with no problems. I am using Remington Ammo I bought at walmart. Didn't want to step up to Reloads and add another Variable until I got things working well with factory ammo.

Thoughts?

[Stu454]

Silly question since you mentioned swapping the mainspring: is the strain screw tight?

[imashooter2]

What does the firing pin measure?

[sixshooter]

The DA trigger pull on my 625 is down to 6lbs 4oz and it runs 100% but all I ever run is Fed primers. If you don't wanna try reloaded ammo pickup some Federal ammo and try it...



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[judge]

Sir - Is your gun a square butt or round butt frame. The square butt models use a longer strain screw. The shorter screw goes on the rnd butt models. If you have a full size screw, and a new mainspring you should not get misfires. Possible damage to the firing pin? Hammer "draging" on the fwd motion?

[vikingthunder]

Brand new strain screw was installed and tightened. I have an extra Firing pin laying around in the parts box, I will throw it in in the morning and measure the one currently installed.

Gun seems barely fired. Unless someone modified it, I don't know how it would have gotten worn enough to cause this.

Sixshooter, I shoot reloads mostly, but I always want to ensure all my guns will shoot anything before I will carry them. so I test them with a variety of ammo's.

[vikingthunder]

Round butt 625-8

No discernible hammer drag

It appears to have an Apex extended firing pin installed. The firing pin protrusion is equal in depth to my N's with apex's, and considerably more than stock.

[imashooter2]

Put a used primer cup over the end of the strain screw and see if that makes a difference. Not a permanent fix, but it can give you a data point.

[tomcatt51]

Originally Posted by vikingthunder

It appears to have an Apex extended firing pin installed.

Take the firing pin out and measure it.
"Too short" S&W pins: .485
"Good" S&W pins: .492-.495 Titanium and probably as good as any.
Apex std: .500
Apex competition: .495
C&S: ~.515
New stock strain screw and spring should fire everything if you're moonclipping them and you don't have an S&W "too short" firing pin and you're fully seating the primers.

[ikor]

Headspace measurement? B/C gap? End shake?

[happy jackson]

I think ikor is on the right track.Several years ago I aquired a 325 airlite pd and had many ftf.I installed a C&S firing pin.Still had a few ftf.I then read on this forum that someone here had the same problem and it was excessive endshake.I bought endshake bearings from Brownells and installed (can't recall if it took one or two of them).End of problem.Also worked the same for a 17-1 that had many ftf.