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Discussion Starter · #1 ·
I got one of the new firing pins(61014) today and immediately installed it and headed to the range to test it. The results were not good. Of 30 rounds, 8 were FTF. I was using Federal automatch in my Mk.3 std. I deliberately used Automatch because it will often give one FTF out of 20 rds. I did not compare the dimensions of the new FP but it is definitely lighter and has a smaller contact patch. If I get motivated next week I will try it with some other ammo.
Stew
 

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I've had a few failures with Federal Automatch. Too bad I have soo much of it.

When I test my 22/45 for function I use CCI SV or Mini Mags. They always function 100%.

Even 1 out of 100 is not good. Your gun should fire Every time.
 

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I am not trying to turn this into an ammo thread, but I agree with AZ. Federal Auto Match is not a good ammo to get a base line with. I am not sure why it is so popular, but it sure isn't what I would call very reliable.

Test the gun with some CCI SV or Mini Mags, or something else from Federal, like game shock. You need to remove as many questionable variables as possible.

I am curious about the weight difference in the FP from the factory installed one to the one you just bought. It really should be within a gram or so, if it is the same metal.

Let us know

Rich
 

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Discussion Starter · #6 ·
Firng pin

I deliberately used automatch as a test because I often get a FTF in 20 rds. I use it for slow fire in bullseye matches, therefore if I got no FTF's in 30 rds. it is probably better. My 6" mk.3 has the original hammer, vq sear, sam's bushing and about 20K rounds. It is cleaned after every match and functions almost perfectly with CCI std (one FTF in 12 matches). The new firing pin has two holes in it, the second hole is for lightening and has material removed along the top which trims the weight down by 27% (according to SGW). My reason for replacing the original was to lessen FTF's (especially with automatch). I plan to put it back in and test it with CCI std. soon and will post the result.
 

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New pin also

I installed the new pin in my '79 RSP a few days ago. I went to the range the next day more to re-zero my sights than try out the pin. As it goes I shot Win 38 gr. HPs and Fed AM. I shoot a lot of AM. My experience just does not comport with many threads I see where numerous FTFs are reported. I typically use AM in my Medalist, BM, HS 103 (when I am out of SV), ATD, CZ 452s, CZ99s, Sav MKIIg, etc.. Other than practicing rapid fire in practice, I shoot pins twice a month in friendly competition. A misfire will kill your evening when a stove pipe, FTE or FTF occurs. The one ammo I do not use with my HS 103 when shooting pins is Aguila SV. It will fail to cycle the slide about 10% of the time. I find this interesting because I use Aguila SV 40 gr RN in my Medalist & BM with no problems. The CCI SV seems to have a little more oomph than the Aguila in cycling the action of the High Standard.

I did not have any FTFs with either ammo used. My firing pin spring and all other parts are original to the gun with the exception of a new extractor and trigger which I replaced along with the firing pin. For that matter, I shoot any and all brands of ammo in the RSP and I really don't even consider a FTF as a probability, but undoubtedly I probably have had some at some point in time. I have had the pistol since 1980.

I do have occasional FTFs, but I don't have enough to relate them to one brand of ammo to another, but as I shoot AM about 90% of the time, logic would dictate that the probability is AM to FTF is true.

As a final note, I looked at the firing pin indent on several cases when I started shooting. The indent was well defined and significant. I also inspected the nose of the firing before installation to see if there was a smooth surface based on the earlier post by SGW. It had no apparent issues at 30X with a lighted hand lens. I polished it a bit anyway with some 1500 grit W/D just for the H-of-it since I also polished the sides and edges of the FP, again mostly just to reduce any friction points that might slow down the lock time. I didn't observe any on the new pin.

VH :eek:man:
 

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addendum

I was at the range this afternoon... I went through 100 rounds of Fed AM through my BM and Medalist (didn't take the RST pistol) with no FTFs or anything else. I will take the Ruger tomorrow and run another 100 rounds.

VH :eek:man:
 

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While the brass might possibly be a bit harder in the auto match than CCI, I would argue that it very well might be your pistol not imparting enough ummph on the rim. When I have FTfs with my 22/45, I swap the "dud" to a 77/22 and try it again 180 degree offset from the last firing pin strike. When I first started shooting my 22/45 it was not uncommon for duds in the 22/45 to fire without issue in the 77/22. After a complete polish of the hammer, firing pin and addition of a tight fitting hammer bushing, the few duds I get, usually Winchester 333 bulk pack hps, are duds in the 77/22 as well. I have had 1 dud auto match round in the last 3 bulk packs.
Also, a lighter firing pin will be more susceptible to light strikes due to friction or gunk in the firing pin channel than a heavier fp.
I would recommend a full polish of the hammer and stock firing pin, a good clean of the extracted cutout in the chamber face, and a tight fighting hammer bushing. (Replace the mag safety if you havnt already.) Also, check the "dud" ammo in a different .22.
 

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I've had a few failures with Federal Automatch. Too bad I have soo much of it.

When I test my 22/45 for function I use CCI SV or Mini Mags. They always function 100%.

Even 1 out of 100 is not good. Your gun should fire Every time.
And so do I, along with many other savvy Ruger Mark pistol owners. CCI Mini-Mags are the BEST benchmark that can be used to test a Ruger Mark pistols function. Why is that? Because those rounds are so dog-gone reliable, and if you have any functional hiccups with Mini-Mags, you know, it's more often than not, a mechanical issue.

Some will try and argue with that, but that's normally just a bunch of flatulence to foul the air and cause strife. Most know the record of those two by now. ;)
 

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Hello again Stew, after reading your thread ( and needing some parts myself) I ordered 2 spare Mk firing pins. I now see exactly what you are speaking about. There is a lightening hole in it, and the top is cut on 45 degrees to lose weight too. I noticed that the portion that strikes the brass is much more "pointy" than the original pin. It appears to have about 50% of the striking area of the original.

One day ( when it warms up and my hands thaw) I will do a side by side comparison on my gun.

Until then, I await your feedback!!

Rich
 

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Discussion Starter · #13 ·
Anouther test

First, regarding the weight. The new firing pin weighed 2.7 gr. or .10 oz.
The old firing pin weighed 3.8 gr. or .13 oz.
Since the first test I put the old pin in for a match and had 1 FTF out of 20 in slow
fire with Automatch and no FTF w/CCI std. in 40 rds. in timed and rapid.
The next day I put the new pin in and tested again. Had 11 FTF out of 30 w/Automatch and 4 FTF out of 30 w/CCI std. I also measured the pins and the
LOA was the same but the distance from the stop pin to the tip of the new pin was
possibly shorter.(hard to measure with a caliper). If SGW or another member has
better instruments they can check this. I have new/old style pin on its way and I
will attempt to repeat measurement again.
 

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I installed one of the new firing pins into my Ruger Mark III Hunter this afternoon and grabbed a full box of Federal Auto-Match.



Using 4 magazines where I loaded each magazine twice with 10 rounds each time, I had absolutely no failures to fire, but I did have one stovepipe and one failure to feed. This pistol was not cleaned after the previous testing a couple of days ago, and the factory extractor is still in this pistol.

After 80 rounds of Federal Auto-Match, and each rim was hit perfectly and deep enough to my satisfaction. No failures to fire. I did polish the very top edge of the firing pin, and then polished the bottom edge of the recoil spring assembly brace that the firing pin slides across. The firing pin does not ride upward as one previous post erroneously reported that they do.

 

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Discussion Starter · #16 ·
Reason for swap

Was to eliminate FTF's with Automatch. There may be some other factor for my results,
perhaps my mainspring is weak? or something else. I did receive the new/old style
firing pin I ordered and measured it in comparison to my original and the new pin and found that the LOA on it was 1.977 as compared to the old and new at 1.975.
So the new style is .002 shorter and my old pin had worn/peened by .002. The new/old style pin is in now and I will use it in the next match and then also test it
with Automatch.
 

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Was to eliminate FTF's with Automatch. There may be some other factor for my results,
perhaps my mainspring is weak? or something else. I did receive the new/old style
firing pin I ordered and measured it in comparison to my original and the new pin and found that the LOA on it was 1.977 as compared to the old and new at 1.975.
So the new style is .002 shorter and my old pin had worn/peened by .002. The new/old style pin is in now and I will use it in the next match and then also test it
with Automatch.
Stew,

I have a couple of suggestions you might try, if you don't mind. When you have some time, send me an email at [email protected]. That way I can send clear pictures from a camera to maybe help with a solution.

There are actually a myriad of things that can, and will, cause light primer hits.
 

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Measuring and comparing the over-all length of each firing pin doesn't take into account where, and how, the firing pin stop pin hole is located in each firing pin. It would be a lot to ask for if that firing pin stop pin location would be the same for every firing pin Ruger has made. That location also controls "firing pin protrusion", which is more important. So, the difference of 0.0020 inch may not mean much, if anything at all.

More important to me, is how deep the rim hit is by the firing pin tip. That can all be calculated once you know what headspace measurement is, firing pin protrusion distance and then rim thickness of the rimfire ammunition you're using.

If anyone is interested in a simple technique used to measure .22 rimfire rim thickness, here's a fairly easy method:



I use a .223 fired case. A .22 rimfire round will slip into the case mouth very easily. I faced the head of the case off to make sure it was perpendicular to the centerline.



Measure the overall length of the cartridge case.



Set your calipers at "ZERO".



Install a cartridge into the 223 case mouth and then measure the case rim thickness.
 

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Discussion Starter · #19 · (Edited)
I like your method of using the .223 case as a fixture. Thanks for sharing it. My method has been to directly measure the case(not quite as accurate). The attached photos show measurements on a case which fired with the new pin and was later chambered and dry fired with the new "old style" pin. The impression from the "new style" pin was .006 (enough to fire) but the new "old style" was .012.
I shot in a match last night using the new "old style" pin and had no FTF's on 20rds. of Automatch and 40 rds. of CCI std.
I plan to test the new pin using Automatch and a newer mainspring assm. (will borrow from my wife's 22/45).
The photo of the case shows the hits from the new" old style on top and the new on the bottom.
Stew
 
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