I took it into the gunsmith today. He took one look at the primers on my brass, and immediately proclaimed that the problem was the spring in the bolt not being strong enough. We took out the bolt, and he was able to easily cock it by hand, something that he usually uses a vise for. The firing pin seemed to protrude just fine. He is going to look for a stronger spring for that action, probably from Brownells. Says Ruger only makes one strength.
Any thoughts?
Posts: 4781 | Location: Story, WY / San Carlos, Sonora, MX | Registered: 29 May 2002
I have a new Ruger RSM in 375 H&H. I've shot about 125 rounds so far. Yesterday, when using factory Speer Nitrex, I had a misfire. Rounds went off properly both before and after the misfire. I compared the indentation on the primer, and while it was dented, it was slightly less than on the fired rounds. What is the problem, and how do I fix it?
Posts: 4781 | Location: Story, WY / San Carlos, Sonora, MX | Registered: 29 May 2002
Sounds like ammo could have had one with bad primer ect. could of had some dirt around firing pin hole. If you are getting good solid fireing pin hits on the rest I just clean the bolt up and see what happens.
Posts: 19712 | Location: wis | Registered: 21 April 2001
Quote: I have a new Ruger RSM in 375 H&H. I've shot about 125 rounds so far. Yesterday, when using factory Speer Nitrex, I had a misfire. Rounds went off properly both before and after the misfire. I compared the indentation on the primer, and while it was dented, it was slightly less than on the fired rounds. What is the problem, and how do I fix it?
Take out the bolt and "de-cock" it. Measure the amount of firing pin protrusion with a dial caliper. Contact Ruger, and find out what the protrusion is supposed to be. Or, if you have no measuring tool, compare it to other of your rifles to see if it protrudes as much as your other gun(s). If not, then perhaps it needs to be replaced. However, I'd bet your ammo is at fault, with maybe a primer or two seated too deeply....
sbt this is a serious issue in my mind....and I truly believe you need to get to the bottom of it. A DG rifle should not have this problem and I'd venture that it's not the Ammo.
Using a precision caliper try to measure the length from the back of the case to the foreward end of the belt and compare this to the fired cases that we're not duds. Them measure the depth of the primer from the end of the case.....I believe this should be .001-.004.
If you can't find at least .010 difference in the dud compared to fired cases I'd be a sending that gun back to Ruger for repairs.
I too suspect excessive headspace.
Posts: 28849 | Location: western Nebraska | Registered: 27 May 2003
Make a headspace gage by soldering on a dab of soft solder just at the top of the belt on an unprimed case. File it down some and chamber it. Measure it from the bottom of the base. The chamber dimension is .220"-.227".
I measured two of my old M 70's and both of them are .228" and they function fine. I don't shoot that many factory loads however.
There is a thread in the archives on this by John Ricks.
Quote: Sounds like ammo could have had one with bad primer ect. could of had some dirt around firing pin hole. If you are getting good solid fireing pin hits on the rest I just clean the bolt up and see what happens.
I had this same problem with a m70. A small metal chip was floating around in the bolt, some times causing the pin not to fall all the way!! Removed it and works great
Damn slim chance! Again I say, check the amount of firing pin protrusion before you start any of the involved drills that others have suggested. This is the first, and simplest, check to make!!
IF you decide to check the headspce, have it done by a professional with the proper tools! Don't try to do it yourself by making up some jim-crack home-made gauge!
Since it is new, if anything is wrong with the rifle, MAKE RUGER FIX IT!!
