Ruger Standard misfire

[Kenstone]

It was worth a try, but I can't see or feel even the tiniest imperfection in or around the chamber.

Attachment 251030

Stoning a slight chamfer on the chamber edge to remove what looks like a knife edge might allow the casing to seat deeper so the bolt closes 100%, all the time.
Take a look at the corner on unfired brass and you'll see a small radius there.
Doing the plunk test will reveal if this is a problem.

[cupajoe]

Years ago I picked up a well used Mark 2 Target for a song. It had extraction issues, which is probably why the owner sold it. I detail stripped it, cleaned, lubed and checked for burrs, no change. I bought a popular aftermarket extractor and still the same problem. I bit my lip, bought a Ruger extractor and bingo, problem solved.

[fatelk]

I never did call Ruger; I just put it back in the safe and continue tinkering with it when I get a chance to get to the range.

I went out again, with all three guns: the Standard in question, my old Standard, and the newer MK2. I've swapped so many parts so many different times between them that I had to be careful to keep track of what goes where.

The chamber is perfect. Rounds plunk in nice and clean. Every little nook and cranny is perfectly clean. I've swapped all parts, including firing pins and recoil springs, from the bolts of the guns that work perfectly, into the problem gun. All to no avail. When I swap the bolt body from either other gun into it, it works perfectly. The bolt from that gun works fine in either other gun. I don't want to throw money into it on parts that don't seem to be a problem. I'm going to try to remember to call Ruger tomorrow, but I don't really expect anything from them.

[Dan Cash]

If swapping bolts between guns eliminates the problem, why not leave the parts swapped. Problem solved.

[fatelk]

The MK2 bolt is different. It functions fine, but the bolt hold-open doesn't work. My old Standard is nickel plated, and I've had it for over 30 years, would rather keep it as-is.

[fatelk]

After looking at all three guns carefully, I think I can finally see a difference. I was under the impression that the rim should always come up under the extractor, and the extractor should never pop over the rim, but when I look closely at slow motion videos of other guns on youtube, it really looks like when the bolt bounces on closing, it somehow releases and pops back over the rim.

When I have all three guns apart, put a round in the chamber, and push the bolt closed by hand, the problematic gun definitely takes slightly more force. It appears that's because it doesn't easily go into the bolt face. The edge of the bolt face opposite the extractor contacts the rim ever so slightly. This interference seems to be the problem. I just did some careful stoning and polishing of a tiny bevel on the edge. Now I can't make the bolt stop on a rim no matter how I try (cycling by hand), where I could before (only on that gun).

It makes sense in a way. I wondered if it was a tolerance stacking issue, since the same bolt works fine in the other guns. I'll give it a try next time I get to the range, and see how it goes.

[EMC45]

Sounds like you got it fixed.

I have a MK2 SS bull barrel my wife got me years ago as an anniversary present. It did not work well AT ALL!! I actually wanted to sell it to get something else it frustrated me so badly. It would hang up on every type of ammo I fed it.

I was shooting at a WMA range once and another shooter noticed my issue and told me to polish the feed ramp as his dad's pistol was doing the same thing and that worked for him. Sure enough my feed ramp had a series of ridges going across the ramp. I guess it was dull cutter day at Ruger. I am very wary about "polishing", with dremmel, anything on a gun. I used a Craytex cylinder and then a polishing bob with Flitz. It now feeds anything I put in it and runs like a champ. It prefers CCI Blazer, Federal Auto Match, but it will eat anything.

[fatelk]

I finally made it out to the range again today, fired 100+ rounds through it, without a single problem!

It's interesting, sure appears that it was a genuine manufacturing defect, in a 45 year old gun. I wonder if the previous owner or owners over the decades ever became frustrated with it.

[reivertom]

I finally made it out to the range again today, fired 100+ rounds through it, without a single problem!

It's interesting, sure appears that it was a genuine manufacturing defect, in a 45 year old gun. I wonder if the previous owner or owners over the decades ever became frustrated with it.

I have never heard of this problem. You might have a one in a million. Now you know how to fix it and never will have to again! :^)

[fatelk]

It was a weird one; that's for sure. It sure wasn't easy to figure out. The geometry of the bolt face was just slightly "off". It wasn't enough to make a difference in the other guns, but I suspect that was due to very, very small differences in tolerance between the guns. I was never able to measure any difference, but clearly they were there.

The amount of metal I removed from the bolt face was very, very small. It sure made a difference though.

[fatelk]

Just thought I'd add one last thing to this thread. I've had this gun out a couple more times now, shot at least a couple hundred more rounds through it, with absolutely zero malfunctions. I'm satisfied that it's fixed.

It also appears to be plenty accurate. I sighted it in today, tapped the rear sight over and filed a little off the top of the front sight. I was shooting 4 or 5 round groups while adjusting it. I think this is my personal best 25 yard handgun group ever:



Admittedly a lucky group, but most of the other groups weren't that much worse. Most were around 1.5". Historically that's the very best I've ever been able to do, open sights with a handgun at 25 yards.