BFD's mkIII

bigfatdave · Post by **bigfatdave** » Thu Jun 04, 2009 2:06 am

This happened multiple times at the range last night, thankfully it was pointed into the backstop every time! I also got a few light strikes, if that might be related. It occurred with "slingshotting" and with the bolt stop lever. We were rather disturbed, and I was looking for any relevant experience before I:
-get into a detailed cleaning/troubleshooting
-take it to Gander for their "safety check and cleaning" they bundle in with firearms purchases
-contact Ruger

We were using federal bulk 550, and this was the first time the pistol had been shot since last cleaning. Previously we have had issues with the sear sticking after cleaning, leaving the pistol unable to properly cock or be placed in "safe".

Post by **Bullseye** » Thu Jun 04, 2009 6:59 am

The inadvertent firing could be related to premature sear release or sear sticking. Is this a metal framed pistol or a polymer framed one? Do you know if the hammer fell during each of these events? How many rounds were in the magazine when you closed the bolt? Was there any auto firing of remaining rounds in the mag? A weak sear spring or a improperly bent short leg of the sear spring could cause a similar event. The sear could be knocked off of the hammer hook upon closing the bolt. I would remove the sear spring and check it for damage/improper bends. I described a similar circumstance to a fellow with a 22/45 in this thread http://www.guntalk-online.com/forum/vie ... 2934#12934 His sear spring leg had be overclocked and bent too far forward causing similar results.

Hope this helps.

R,
Bullseye

bigfatdave · Post by **bigfatdave** » Thu Jun 04, 2009 2:11 pm

Bullseye wrote:1-Is this a metal framed pistol or a polymer framed one?
2-Do you know if the hammer fell during each of these events?
3-How many rounds were in the magazine when you closed the bolt?
4-Was there any auto firing of remaining rounds in the mag?

Thanks for the reply, Bullseye.

1-Metal-frame, unmodified mkIII (bull barrel)
2-I believe it did, but I'm not 100% sure
3-From 10 to 2
4-Wouldn't that meet the definition of full-auto?

You recommend a home detail strip before putting it in the hands of a professional? I haven't worked up the courage to go further than stripping for cleaning yet, but perhaps I need to. The only local pro is the gunsmithing service at the Gander Mountain I bought this pistol from, and I don't know how competent they are, or if they will just end up sending it to Ruger.
This pistol has been problematic since I purchased it. It will fail to eject the fired case, and then attempt to load a fresh one from the mag with the fired case wedged in next to the guide rod at the top of the receiver. The sear sticks during re-assembly. The bolt stop pin requires hammering in and out every time.
I have another mkIII (target model) and it doesn't have these issues. In fact, MrsBFD and I enjoyed the first mkIII so much, we bought another so we wouldn't have to share at the range. You would think that with all the stuff Ruger added to the mkII design to make the mkIII I wouldn't be having malfunctions that lead to a discharge!
Well, enough venting ... I know you know the Ruger rimfire pistols inside and out, should I do a detail strip, is there anything to check before getting that far in? Are there any pictures that would help?

blue68f100 · Post by **blue68f100** » Thu Jun 04, 2009 5:00 pm

Here is the link that bullseye put together. It's a very good tutorial. Just have your gun on the desk while you step through the guide and you will be fine.

http://www.guntalk-online.com/detailstrip.htm

bigfatdave · Post by **bigfatdave** » Thu Jun 04, 2009 5:45 pm

blue68f100, I nerved myself up and got MrsBFD reading me steps, your detail strip is easier than it looks, Bullseye!

The issues seems to be being caused by a bent/cracked sear pivot pin (part #49 on the exploded diagram). That was the only smoking gun I found in there, besides the sear being caked in crud.

Called Ruger in Arizona, after a few minutes on hold I talked to a very helpful representative (Lisa) who promises me a shipped replacement part in 7-10 days.

So now I get to have a pistol living in a plethora of baggies, and then to the re-assembly! I'm not afraid to do the mag safety delete or to install VQ parts now either, so hooray for consumer empowerment!

greener · Post by **greener** » Thu Jun 04, 2009 7:29 pm

Congrats on screwing your courage to the sticking place and successfully doing the detail strip, BFD. Bullseye's excellent instructions demystify the process. Now it's time to go for the VQ parts, you will like the results.

blue68f100 · Post by **blue68f100** » Thu Jun 04, 2009 8:00 pm

Glad you found the cause. And that you took the urge to do it. Now you can do a detail cleaning every 700-1000 rounds and keep it running smoothly. Bullseye's tutorial are very good.

The sear pin is suppose to have a interface fit on the right side. So there should be 1 end that will not install freely in to hole.

Now is the time to do upgrades while you have it torn apart.

If you have your parts laid out in a way to help in reinstalling, take some photos so it will jog your memory.

bigfatdave · Post by **bigfatdave** » Thu Jun 04, 2009 8:48 pm

I found the detail strip much easier than I feared. It is too late to take pictures, but the exploded diagram from Ruger was a help, we used it to double-check everything as we labeled and bagged it.

I've been thinking about those VQ parts, particularly the sear and hammer assemblies, plus removing the mag interlock. Right now, I'd like to get the whole thing back together and working in stock configuration before ordering the (surprisingly inexpensive) upgrade components, and then upgrade one pistol completely before moving on to the next. I had planned on ordering the Accurizing Kit and an extractor for both.
Has anyone used the VQ magazine ejector?
https://www.volquartsen.com/products/87 ... uger-mkiii

greener · Post by **greener** » Fri Jun 05, 2009 12:05 am

It will go back together slightly harder than it came apart. I've pinned the thumb safety and hammer assembly with a jeweler's screwdriver or finishing nail to hold them in place while I inserted the hammer pin. Holds them in place and makes them a bit easier to line up.

Post by **Bullseye** » Fri Jun 05, 2009 6:47 am

Good job! Mustering up the courage to go beyond what you are comfortable with is a monumental task. Just follow my instructions carefully and all will be well, and if there's a problem just post here and I or one of the many members will assist you with the reconstruction of your pistol. Practice taking it down several times and you won't have to look at the detailed stripping diagrams very often.

R,
Bullseye

bigfatdave · Post by **bigfatdave** » Thu Jun 11, 2009 7:20 pm

Well, the part arrived from Ruger in the mail today.
I got the pistol back together with only minor wailing and gnashing of teeth (damn tiny parts! Damn tiny gaps in the frame!) and I got a good function check, so off to the range we went.
No more slam fires, nice crisp trigger (it was always a bit off compared to our other mkIII, I had chalked that up to a lack of wear-in) ... but now the bolt won't quite make it back to battery about 1/3 of the time. The trigger will lock back after a shot, and the bolt will be ~1/4" away from the full forward position ... the slightest tap, or even wiggling the trigger will generally allow the bolt to snap forward that last bit.

So I can't report 100% success, but I did get the main problem fixed ... now to diagnose what I did wrong during re-assembly. Perhaps I de-lubed something and didn't re-lube?

Post by **Bullseye** » Thu Jun 11, 2009 10:05 pm

Check the left grip panel and the hammer pivot pin. The pivot pin may not be all the way in and that has the hammer cocked slightly. The grip panel must be tight against the frame to keep the hammer pivot pin secure.

R,
Bullseye

bigfatdave · Post by **bigfatdave** » Mon Jun 15, 2009 8:37 pm

Bullseye wrote:Check the left grip panel and the hammer pivot pin.

Bullseye, you are my hero today, That explains why the L panel didn't sit flat during assembly as well.
Off to the range to test, your diagnosis was correct. If I didn't know better, I would think you were sneaking into my safe as I sleep to poke about the internals of my Rugers.

Post by **Bullseye** » Mon Jun 15, 2009 8:40 pm

Lots of experience Dave. Your detailed description of the problem's symptoms allows me to deduce the problem and make corrective suggestions.

Have fun shooting that pistol!

R,
Bullseye

bigfatdave · Post by **bigfatdave** » Tue Jun 16, 2009 12:11 am

Worked like a charm, now the only issue is the upward ejection resulting in a little tiny trainwreck behind the chamber*, hopefully VQ will get my box of parts shipped soon, because I'm really hoping their extractor fixes the ejection issue.

*less than 5% of the time, perhaps once in 3 magazines.

GunTalk-Online.com

BFD's mkIII

BFD's mkIII

broken sear pivot pin

Repair and range report