Marlin 39A FTF's

[TMan]

One of the nice things about S&W pistols is the suffix. For example: 686-1, 686-2...

Marlin hasn't done that. Consequently, I ordered the wrong reduced power hammer spring and it wouldn't even fire certain brands of ammo. I got the right spring, still reduced power, but I've still had a few FTF's. My first thought was that the firing spring was too strong. No cigar - it doesn't have a firing pin spring.

I took the firing pin out, there was a pin holding it in, but that didn't show in the manual that I had - must have been an addition for the latest suffix.

I stoned the front of the firing pin to make the surface area slightly smaller and polished the side surfaces of the spring. After putting it back into the bolt, I can shake the bolt and it rattles. If this doesn't fix it, I guess I'll have to go back the the original spring, which will give me a heavier trigger pull. I'm not wild about doing that, but I don't know what else I could do. What I'd like is a spring just slightly stronger than what the Wolff reduced power spring is.

I'm getting around 30% FTF's the last time I fired it. I'm planning on going to the range this morning to see how it does after polishing.

Modified to add: Back from the range. Got 7 FTF's out of 50 rounds.

[MLB]

Wasn't it you TMan that mentioned belt sanding a spring over a dowel to reduce the power? Perhaps you could get an extra few standard power Marlin springs and get one that's just right.

[TMan]

MLB, it is that barrel shaped thing. I thought about maybe getting a standard power of the old straight spring, and then giving it the belt-sander treatment. The problem is that I don't know of a way to measure my results i.e. I can't measure the hammer hit strength.

[MLB]

Should be proportional to the spring constant I'd think. You can measure that with your trigger pull scale. (lbs/in right?)

[TMan]

The trigger scale doesn't go high enough. I tried pulling back on the hammer with the scale and it went off the end of the scale.

I'm getting ready to go back upstairs and do some more gun work. I'm going to make a shim to go between the spring and the bracket. That should put more tension on the spring, providing it won't completely compress and prevent the hammer from cocking.

I've got to fix this. I can live with a trigger that is a little heavy; I have less tolerance for a creepy trigger; but I can not live with a gun that gets FTF's.

[MLB]

Yes, I suppose that should have been obvious. Perhaps a fishing scale would work better (unless you use your trigger scale for those too ;D )

[TMan]

MLB, my brother has a cottage on Lake Ontario. He took me fishing once. I told him: "I don't put anything on a hook, and I don't take anything off a hook."

I don't own a fishing scale. I gave up on the shim idea and went back to the factory hammer spring. Not that bad. It only added 4oz to the trigger pull. With certain ammo there wasn't any FTF's, but I wanted to shoot the Wolf Match Extra, and I had FTF's with it. It should be okay now, and I can live with the extra 4oz.

My wind chime has finally stopped. We had 50 mph gusts today. So I think I'll go to the range tomorrow. I got the Savage down to to 2lbs, so I'll see how those 17 HMR's work tomorrow. I was having accuracy problems with it the other day, but it was because of me trying to use the parallax settings on the dial instead of tuning it out. (Simmons scope 6.5-20x50).