Fitting an extended firing pin block...

[Bapple]

Getting ready to tackle my new parts install/polish on my stock 2.  Only thing that has me a little concerned is fitting the new extended firing pin block.  Any tutorials or help that you can give or point me to would be greatly appreciated.  Thanks

[Bapple]

You got it.  That's what I will do.  I'll report back if any problems arise, thanks!

[MemphisMechanic]

Procedure I went with:

Polish and install it.

Dryfired it a few dozen times. Pulled the pin out, and found peening beginning to appear on it from striking the block.

Okay. So now I looked at how it works. Okay. This is the opposite of an M&P Glock or most striker guns: They block when down, and are lifted up to clear via the trigger bar. The Tanfo blocks when up, and is held there by the sear. When you pull the trigger the sear leg lowers, and the block drops so that the firing pin can hit the round in the chamber.

So...

Cock the hammer and poke it with a punch, and find the pin won't pass the block without trigger pulled. It goes in 1/2" and stops cold. Okay. Safety works. (This fact needs to remain when youre finished.)

Find the position where the hammer will barely fall, then hold the hammer back and keep your trigger in that spot. If your gun is like mine, you'll now feel a noticeable catch when attempting to poke the firing pin forward past the block. This means that the block is up too high when the trigger breaks and the pin is hitting it when you fire.

To fit the block, you have two choices on where to remove material:

I chose to fit the tab that engages the block, not the bottom where the sear lifts it. Reducing either spot will allow the pin to bypass the block earlier in the trigger pull, by placing less of the block in front of the pin.

It's important to keep either surface square, and to be very patient. A thousandth or two is a big change, and you don't want to disable the safety. 

Mine disengages completely 2/3s of the way through the trigger pull now, after a couple of hours of filing and double checking.

Edited December 8, 2016 by MemphisMechanic

[nydde]

On 2016-12-07 at 4:28 AM, MemphisMechanic said:

Procedure I went with:

Polish and install it.

Dryfired it a few dozen times. Pulled the pin out, and found peening beginning to appear on it from striking the block.

Okay. So now I looked at how it works. Okay. This is the opposite of an M&P Glock or most striker guns: They block when down, and are lifted up to clear via the trigger bar. The Tanfo blocks when up, and is held there by the sear. When you pull the trigger the sear leg lowers, and the block drops so that the firing pin can hit the round in the chamber.

So...

Cock the hammer and poke it with a punch, and find the pin won't pass the block without trigger pulled. It goes in 1/2" and stops cold. Okay. Safety works. (This fact needs to remain when youre finished.)

Find the position where the hammer will barely fall, then hold the hammer back and keep your trigger in that spot. If your gun is like mine, you'll now feel a noticeable catch when attempting to poke the firing pin forward past the block. This means that the block is up too high when the trigger breaks and the pin is hitting it when you fire.

To fit the block, you have two choices on where to remove material:

I chose to fit the tab that engages the block, not the bottom where the sear lifts it. Reducing either spot will allow the pin to bypass the block earlier in the trigger pull, by placing less of the block in front of the pin.

It's important to keep either surface square, and to be very patient. A thousandth or two is a big change, and you don't want to disable the safety. 

Mine disengages completely 2/3s of the way through the trigger pull now, after a couple of hours of filing and double checking.

Great post, thanks!

[MemphisMechanic]

13 minutes ago, nydde said:

Great post, thanks!

I just noticed that the image is incorrect though!

You either file down the bottom of the firing pin block which the sear pushes on. Thats the surface you see sticking out the bottom of the slide...

... or you file down the "tab" that is circled in the picture. That part is correct.

The larger circled area is wrong. That would be the top of the block where the spring hole lives, and removing metal here won't affect the firing pink block's timing.

[nydde]

Yea got that part, we have a saying here "misunderstand me correctly"  

[SCTaylor]

Memphis - Is that 2/3's of the trigger from the initial trigger position for DA? I would assume so. How far back from breaking an SA shot is the block de-activated? 

[MemphisMechanic]

As long as the firing pin isn't impeded when the DA shot breaks you won't have any issues. I made that happen and then clearanced just a hair more.

I threw "two thirds" out there mostly as a generalization.

[johnbu]

You should update the photo to avoid confusion!

3 hours ago, MemphisMechanic said:

I just noticed that the image is incorrect though!

You either file down the bottom of the firing pin block which the sear pushes on. Thats the surface you see sticking out the bottom of the slide...

... or you file down the "tab" that is circled in the picture. That part is correct.

The larger circled area is wrong. That would be the top of the block where the spring hole lives, and removing metal here won't affect the firing pink block's timing.

 

[MemphisMechanic]

34 minutes ago, johnbu said:

You should update the photo to avoid confusion!

Done. The photo in my first post is correct now.

Edited December 8, 2016 by MemphisMechanic

[MissionaryMike]

Don't know how I missed this one, but this is another great tutorial. Thanks, @MemphisMechanic.

 

 I just checked my firing pin with the position where the hammer will barely fall, as I can feel it catching on the hammer hooks.  I do feel the pain catching on the FPB just lately. Looks like I have more meddling to do on this gun. Yay!

[B_RAD]

Here's a pic of my stock FPB and the extended FPB I bought.  No fitting required. 

 

So, just like everything else Tanfo makes, there's a wide swing in tolerances.  

 

 

[Nathanb]

It does not appear I needed to fit mine either. I've got close to 500 rounds through to and there's no peening or signs of it impacting the firing pin

[taxil343]

Thanks for the info. I currently have the FPB out of the gun. Will re-install and do some dry fire tonight and check it out. 

[MemphisMechanic]

There's a simpler test than I described with the writings above:

 

Hammer cocked, ensure the firing pin stops cold if pushed forward 1/4" or so, with a small punch.

 

Pull the trigger slowly until it's in a point where the hammer will just barely fall, hold the hammer back with your thumb, and keep the trigger in that position. You should be able to push the firing pin all the way through without it catching on the block

[taxil343]

I'll try it out in a couple of hours. I'm hoping mine will not require fitting I'm thinking it may. I had some issues with DA light strikes with a brand new gun and a 12lb PD spring. I pulled the FPB and put in a 13lb Wolff spring I had and the gun has run 100% since. I'm hoping the light spring/new gun/good but not great polish job was to blame and not the FPB. 

[Avenida]

Just a quick shout out to MemphisMech! I hope he reads it.

With your videos and all these post, I was able to set my Stock II AUS with all extreme parts with a lot of confidence that I would do a good job. I took my time and I polished all the internals.

 

My DA trigger is a little bit over 5 lbs and my SA, well, very light.

 

I got a few light strikes with S&B primers, at least five in 300 rounds, Federal 100% ignition. However, upon my return I checked the gun and noticed a that the FPB and the FP were colliding into each other and there was peening on the FP. So I found this post. This is the only forum with all this info here.

 

I can't thank you enough and BTW, I love this pistol. It is a pleasure to shoot (I also owned a Shadow 2 and this pistol puts the shadow 2 to shame).

 

Cheers and thank you again!

[MemphisMechanic]

8 hours ago, Avenida said:

Just a quick shout out to MemphisMech! I hope he reads it.

 

With your videos and all these post, I was able to set my Stock II AUS with all extreme parts with a lot of confidence that I would do a good job.

 

Cheers and thank you again!

 

Glad to hear the videos and our discussions here on BE have helped someone else. That’s what they’re intended for. Enjoy the gun!

[Avenida]

cheers !

 

[Avenida]

On 2017-02-01 at 3:40 PM, MemphisMechanic said:

There's a simpler test than I described with the writings above:

 

Hammer cocked, ensure the firing pin stops cold if pushed forward 1/4" or so, with a small punch.

 

Pull the trigger slowly until it's in a point where the hammer will just barely fall, hold the hammer back with your thumb, and keep the trigger in that position. You should be able to push the firing pin all the way through without it catching on the block

 

Ok well, after ruining my 3rd extended safety, I think I am finally getting the hang of this. lol

 

I need a little bit of help, I have all extreme parts on my stock II so this is not a problem of parts in-compatibility.

 

I tried trimming the little notch and also the head (of course, in different safeties), I have had the same results with both however trimming the head is much easier and faster once you know the dimensions you need to trim for.

 

After 3 trials, I have decided that the best way to trim this (this is costing me a fortune) is by trimming the head, I always take my time and  I know now, after a meticulous 3rd attempt that the safety starts failing after it is shorter than 0.501.

 

I guess I need to figure out now, what do you guys mean with 'when the hammer barely falls' to properly trim the safety. My guess is this would be at 0.502 in my case. However, if I leave it that long, I can push the pin through but I can feel a slight drag in between the safety and firing pin.

 

Please note that it is not grabbing, but it is dragging, meaning it is slightly slowing down the firing pin.

 

My problem is that I do not know what is the correct setting for this and I keep on trimming it too short.

 

If I keep trimming until I cannot feel any drag, then, the safety will fail and can be pushed through when the hammer is  cocked (there is a bit of resistance still but it is possible to poke it through).

 

This is extremely difficult to explain by text but I am hoping that my explanation is clear.

 

 

 

HELP! 

 

thanks guys

 

 

Edited October 17, 2017 by Avenida

[johnbu]

Just to be sure.... you are pulling the trigger FULLY to the rear while holding the hammer back while poking the firing pin... right?

 

If so, have you also backed the trigger OT screw way out, so the sear can fully lift the safety?

[Avenida]

On 2017-10-17 at 10:24 PM, johnbu said:

Just to be sure.... you are pulling the trigger FULLY to the rear while holding the hammer back while poking the firing pin... right?

 

If so, have you also backed the trigger OT screw way out, so the sear can fully lift the safety?

 

Hi John, I was using Memphis mechanic description as in 'barely falling', or in other words, no, the trigger was not being pulled fully, just enough to barely clear the hammer hooks because that was my interpretation of 'hammer barely falling' as described above.

 

I did contact Memphis for help - Lol - and he said that his  description is not accurate, so I am not going to hold him to it, he probably wrote that as he was learning the mechanics of the guns, the same I am doing it now.

 

By the writing above, I thought that the hammer would be quicker than my finger depressing the trigger fully and once the hammer is released the firing pin would impact the safety if the block was not fit to clear when the sear barely clears the hammer hooks (WHAT A MOUTHFUL THAT IS ) , which is why I was setting the safety to clear on that point, on the 'barely falling point'.

In my mind I was battling with the question: what is the point of the safety if it clears completely once its barely disengages the hammer hooks? I could not understand how that would help anything,  and it seemed a very silly useless safety if that was how it worked. So I experimented with this using the guidelines posted. Again, no hard feelings. It was probably a combination of things and I do not blame Memphis, he writings, not only on this matter but also on other tanfoglio things, is what brought me to this forum and I appreciate his help very much. Thank you.

 

So, in regards to the over travel screw, I did notice the over travel screw and how that would affect the sear 'dis-engagement', this is something I learned with the Shadow 2 as you can tune this gun to release the sear 'just barely' to clear the hammer hook, as this gun has no firing pin safety. So yes I was aware of it and made sure it had enough space. However, I have not modified the screw position (left it as it came from the factory) as in my opinion is has enough clearance (there is a visible gap of maybe 1.5 mm when the trigger is fully depressed).

 

Perhaps you could give me an idea of how much clearance should I allow? Maybe I am exceeding it and I should tune for 1/4 less than what I have now. Just to improve trigger feel.

 

I did try pulling the trigger fully, and, during this test, all my safeties where clearing without touching the firing pin when the hammer is depressed fully so that is reassuring, but perhaps a minimum adjustment would be required just to maximize reliability. I guess that the best way to test this would be by dry firing and see if there are marks on the pin or safety. That would certainly make it easy.

 

To recap:

Based on your comment above, I can assume that the firing pin should pass the punch test while the trigger is pressed fully (which I was not doing). That makes more sense, as it will catch the firing pin in the event the hammer inadvertently falling.

 

 

 

 

Edited October 19, 2017 by Avenida

[johnbu]

6 hours ago, Avenida said:

To recap:

Based on your comment above, I can assume that the firing pin should pass the punch test while the trigger is pressed fully (which I was not doing). That makes more sense, as it will catch the firing pin in the event the hammer inadvertently falling.

 

 

Yes, that's how i do it.

 

I REMOVED the OT screw completely from mine. Trigger feel is much more modulated by sear and hammer hook interface. A light buff (sear face is only surface hardened and polishing can burn through the hard part).

 

Using the patriot defense reduced power sear spring and trigger spring will also lighten up the SA.

 

Mirror bright polishing the all the pins and holes will make it crisp like a high dollar custom gun. Do that and check every 500-1000 rounds, polish any parts that show signs of rubbing. 

[Avenida]

Thank you!

[Trinimon]

Necro thread awakening.

 

Thanks for this write up. I found out that after installing a Titan hammer in my Ltd. Custom, my factory FP block safety no longer functions. I've ordered an Xtreme block so I'll be referring to this thread when I have to fit it.