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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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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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Discussion Starter · #10 ·
Firing pin

Ran 20 rds. of Automatch in slow fire this evening with one FTF W/old firing pin. Ran 40 rds. of CCI std. in timed and rapid with no FTF W/ old firing pin.
 

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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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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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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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Discussion Starter · #22 ·
That would work as they are the same part but would probably not prove anything as they would both have the old style pin in new or almost new condition (my wife hardly uses her 22/45). Good thought though. I will probably order a new mainspring for my Mk.3 and replace it at the end of the matches in March. As it is now, with the new/old style pin it is functioning well but it should work with the new style pin also.
Stew
 

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Discussion Starter · #26 ·
New mainspring makes a difference

That would work as they are the same part but would probably not prove anything as they would both have the old style pin in new or almost new condition (my wife hardly uses her 22/45). Good thought though. I will probably order a new mainspring for my Mk.3 and replace it at the end of the matches in March. As it is now, with the new/old style pin it is functioning well but it should work with the new style pin also.
Stew
I finally got around to replacing the mainspring and now the pistol with the "new style" firing pin will fire Automatch with no FTF in 100 rounds (including some from the same batch as the original test). FYI- the new mainspring measured at 2.341 and the old one at 2.269, meaning that the old one was .072 shorter. There were aprox. 50,000 rounds thru this pistol before the spring was replaced.
Stew
 

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Discussion Starter · #32 ·
Stock spring

Just to clarify, my replacement spring is a stock Ruger part and the difference in length is due to set/wear. BTW, in the absence of a neat fixture for spring replacement like yours I drilled two holes 1/16"apart on opposite sides of the housing and used two small screwdrivers to "lever" the spring down in the housing
far enough to allow replacing the ball and lever and put the pin back in. In any case, with the "new style" firing pin and the new mainspring my pistol now runs 100 Automatch without a FTF.
Stew
 
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