Ruger Mark II Hammer Spring

[haze10]

For the Ruger Mark II or III. I'm tired of the soft primer strikes. I really want to install a slightly strong hammer spring. But I can find is a Wolf that is 'lighter'. Has anyone matched a machine spring that will do the job.

[Toolguy]

You can stretch the original spring and it will have more tension when re-installed.

[haze10]

I thought about stretching the spring, but I've always heard that deforming a spring like that would not last. In other words it would work initially but quickly weaken. Are you sure this works longterm.

[Toolguy]

If a spring is properly tempered it will hold the new shape indefinitely. I would assume Ruger knows how to temper springs.

It's worth a try. It wouldn't hurt to get a new one for a spare too.

[kframe_mike]

I've had some light strikes with my MKII as well.I've found that I have to keep this one pretty clean to run right.The thing you really have to watch is the face of the bolt,where the rim sits.Rugers limit the travel of the firing pin to prevent damage to the face of the barrel from dry firing.All it takes is a little crud build up on the face of the bolt and the firing pin just can't get to the rim very well.A couple of things I was thinking about doing to mine were:1 Check that the firing pin has full and free travel,I've already deburred it,maybe adjust for more travel.2 Maybe drill a hole through the hammer to lighten/speed it up for more energy to the pin,like the Volquartson and Clark trigger kit hammers.I don't know if I'll get to the hammer or not,as I'm thinking about dropping in a trigger kit to shoot Bullseye with it anyway.Just some ideas,-Mike

[Bill H]

Are you sure the ammo isn't the problem? Remington golden bullets are great for misfires in my guns.

[mpeltier]

Are you sure the ammo isn't the problem? Remington golden bullets are great for misfires in my guns.

Ding! Ding! Ding! I think we have a winner

Seriuosly, i think i got to much sun shooting today. Ammo would be a very good possibility as to the problem here.

[haze10]

I've tried all kinds of different ammo, but it doesn't help. I keep getting light indents. I've replaced the main spring, firing pin, etc, but no luck. I actually think it may be a lock up issue with the bolt, but don't want to spend the money on a new bolt to experiment.

Generally, I don't think lightening the hammer would work, most cases that would cause lighter strikes. But you may try drilling a hole and filling it with lead, to make it heavier. I'd try that but Ruger won't sell replacement hammers, because too many folks want to defeat the Mark III safety features with a Mark II hammer.

[Smokecloud]

if you have any real mileage on your mk II, you might check the length of your firing pin as well. I rebuilt mine at almost 50k rds, it started having misfires and ejection problems. I bought a new firing pin and found that it was about 1/16" longer and the tip was more prominent than the old one. It had beat itself flat and shortened. I also replaced the hammer spring along with all the springs in the gun. New exctractor and all problems were solved.

if your gun is fairly new, then I would suggest looking for burrs or high spots on the sides of the hammer, firing pin and other related parts that could cause drag, then polish them a little. Your reliability should improve if done right.

Brownells has all the factory replacement parts at a reasonable price.

[haze10]

My Mark II has a lot of mileage on it. I have a Volqueston sear and trigger and extractor, new ruger firing pin, firing pin return spring, main hammer spring, and the recoil spring. Everything slides very easily and there no hangups. The pistol works reasonable good when its clean but after 30 rounds or so acts up. I thought a stronger main spring might help.

[kframe_mike]

Jeez haze10,sounds like you covered all the bases and then some.The only other thing I can think of is headspace maybe?I know some folks with suppressed 10/22s,and one of the things they do for reliability is to have the bolt face trued up for minimum headspace.Other than that I'm stumped.

[Smokecloud]

I have the volquartson setup in mine also, they work nice. Sounds like you have covered most all basis. The only thing I can think of is in the cleaning. I have to be very careful in cleaning mine and pay extra attention to the area in the top of the receiver just above where the bolt rests. if you dont use a toothpick or something similar to remove all of the buildup there, my gun will not function. A toothbrush will not reach it and sometimes the gunk looks like it belongs it blends so well. That will cause some bolt problems because it doesnt close completely. The other problem I had after I rebuilt it, was some of the bake on finish I applied, was inside the receiver tube and caused some friction on the bolt, after I removed it, all things worked flawlessly again.

Did you put the trigger kit in to fix the problem or has it the problem just began since you installed it?

Edited July 27, 2008 by Smokecloud

[mpeltier]

Here is something to check. Inside the bolt with the firing pin is a rebound spring and a little piece of sheetmetal called a rebound spring support. Check that both are there and installed correctly if either are missing or not installed correctly it will result in unreliable ignition.

[haze10]

Replaced the firing pin, the firing pin return spring, and that little bent metal piece that supports the return spring. The gun was acting up when it was stock. At first I change to a Volsq titanium firing pin for $30 but that didn't help. I checked the sear to make sure it wasn't dragging on the hammer as it rotated. The only thing I can guess is happening is that the bolt is not closing 100% on the cartridge. But I can't figure out how that is happening. As far as cleaning, I've been stripping the Mark II to its pieces for years. Everything is clean.

[Bill H]

You could also send it back to Ruger and let them fix it. Take out all the aftermarket parts first though.