I have a Ruger Mark II with a FTF problem that I just can't fix and I have tried almost everything. Sometimes one in three. The failed round has the same indent as the fired ones. The indent is a little light struck but I would think sufficient. I have tried five different high quality ammo, Federal, Rem, Win, Aquila, Blazer, and the results are the identical.
Now I have modified the gun recently with some aftermarket parts. I put in a Voulquartsen sear, and trigger with under/overtravel adjustment.
The hammer catches on the sear each and everytime, and the trigger engages the sear and drops the hammer each and everytime. There is always an indent, just doesn't seem to be enough.
Here is what I tried:
I replaced the fire pin and firing pin return spring. I bought a Voulquartsen titanium firing pin and tried that, no difference. I bought a Ruger replacement trigger, no difference. I took the original firing pin and filed the elongated stop hole further to let the pin fly farther before engaging its cross pin, no difference.
I changed the recoil spring. No difference.
I cleaned and scraped the breech face and the bolt face clean as a whistle. Live rounds will fall with gravity and seat into the chamber so there isn't any drag or binding on the cartridge entering the breech.
Checked to make sure all the cross pins on the hammer, as well as all other cross pins are supported both sides. They were.
There are only of couple of things I can thing of.
1) There is a bit of wobble, about 1/16", when you wiggle it on its pivot. There is almost the same distance clear between the hammer side and the safety lever. I checked the parts manual and everything is assembled right, and a web photo I've seen shows the same amount of play. The cross pin and the hammer pivot sleeve appear okay and this play may have always been there. I've thought of making a 'washer' to fill in the gap on the left side alongside the safety lever, but don't thing there is room as the hammer strut pin is very close. I could order a new hammer, sleeve, and pin as a next step to try.
2) The new sear may have changed the angle of the hammer. Maybe it engages a bit higher so it doesn't have enough travel to develope inertia. But this can't be a large difference as the sears are near identical in size.
3) The main spring may be getting weak after 20 years, but I have never heard of one of these wearing out. Changing it looks to be near impossible. I don't believe that Ruger sells the 'assemble' all together as a spare part.
I doubt I could send it to Ruger Service with the aftermarket parts. I put them so I can take them out, I just don't want to as it took a long time to set the travel stops to get them just right, assembling and dissembling the whole trigger group twenty times.
Anyone have any ideas? I've worked on a lot of guns in my time and could fix almost all of them, but this has me stumped.
Now I have modified the gun recently with some aftermarket parts. I put in a Voulquartsen sear, and trigger with under/overtravel adjustment.
The hammer catches on the sear each and everytime, and the trigger engages the sear and drops the hammer each and everytime. There is always an indent, just doesn't seem to be enough.
Here is what I tried:
I replaced the fire pin and firing pin return spring. I bought a Voulquartsen titanium firing pin and tried that, no difference. I bought a Ruger replacement trigger, no difference. I took the original firing pin and filed the elongated stop hole further to let the pin fly farther before engaging its cross pin, no difference.
I changed the recoil spring. No difference.
I cleaned and scraped the breech face and the bolt face clean as a whistle. Live rounds will fall with gravity and seat into the chamber so there isn't any drag or binding on the cartridge entering the breech.
Checked to make sure all the cross pins on the hammer, as well as all other cross pins are supported both sides. They were.
There are only of couple of things I can thing of.
1) There is a bit of wobble, about 1/16", when you wiggle it on its pivot. There is almost the same distance clear between the hammer side and the safety lever. I checked the parts manual and everything is assembled right, and a web photo I've seen shows the same amount of play. The cross pin and the hammer pivot sleeve appear okay and this play may have always been there. I've thought of making a 'washer' to fill in the gap on the left side alongside the safety lever, but don't thing there is room as the hammer strut pin is very close. I could order a new hammer, sleeve, and pin as a next step to try.
2) The new sear may have changed the angle of the hammer. Maybe it engages a bit higher so it doesn't have enough travel to develope inertia. But this can't be a large difference as the sears are near identical in size.
3) The main spring may be getting weak after 20 years, but I have never heard of one of these wearing out. Changing it looks to be near impossible. I don't believe that Ruger sells the 'assemble' all together as a spare part.
I doubt I could send it to Ruger Service with the aftermarket parts. I put them so I can take them out, I just don't want to as it took a long time to set the travel stops to get them just right, assembling and dissembling the whole trigger group twenty times.
Anyone have any ideas? I've worked on a lot of guns in my time and could fix almost all of them, but this has me stumped.