Help with Understanding Firing Pin versions

[JimGP100]

I’m down the rabbit hole of trying to figure out Ruger’s firing pin situation.

Q1: My understanding is that revolvers from about 15-20 years ago+ have the push fit system. The bushing (some appear to have a notch for a rod/pin too, some don’t), the spring and the pin. Newer revolvers have a screw in “plug,” and the spring and the pin. These have spanner wrench holes to unscrew, visible from under the hammer/transfer bar. Does all this sound correct?

Q2: The firing pin part itself…. Is not compatible between systems? Let’s say I had a “Ruger GP100 firing pin” spare part: it’s not interchangeable between the two systems. I need to have a bushing-era pin or a screw in plug-era pin. Is that correct?

Q3: Depending on Q2 anyway, are SP101 and GP100 firing pins theoretically interchangeable?

 

[contender]

Welcome to the Forum!

I'm not a double action expert. Far from it. And I focus mostly on the Old Model Single-Actions.
BUT,,, I'm sure one of our resident DA experts will chime in soon. One who does a lot will be RoninPa.

 

[rugerguy]

...yes, I was last working on "fixed" , "pivot"( rivet) and "rebound" style pins, sorry, but I'd guess ( hope) Ron will chime in...........:unsure:;)

 

[NikA]

Don't have a definitive answer, but Bowen lists 2 eras of Ruger DA firing pin (press-in and screw-in) and there is only one return spring available from the usual sources for SP, GP, RH, and SRH, so I'd say you're correct on Q2 and the answer to Q3 is yes.

 

[RoninPA]

From what I have found, the actual firing pin for the GP100 is the same for the different "generations", it is just how they are held in place that changed (from the press in with a pin to hold it in place to the screw in). I also checked, and even the firing pin for the .22 GP100 is the same, the only difference is where it is placed in the frame to correctly contact the rim of the .22 cartridge.

From checking a few places it looks like the SP101 firing pin has a different part number than the GP100 firing pin, so without having one of each in my hand I couldn't say for certain if they are different. And again, the SP101 firing pin is the same for the center fire and rim fire guns, just the placement of them in the frame is different.

Remember, Ruger was/is known for its fugality, if they can use the same part for multiple firearms, they will do it, that helps keep costs down. Oh, and the firing pin for the Redhawk and the Super Redhawk is the same firing pin as used in the GP100.

Some more giggles about Rugers frugality, the GP100 firing pin was originally used in the Six series revolvers (Security Six, Police Servicer Six and Speed Six) which came out in 1970. So you can see how long they hve been using that style of firing pin.

Oh, as for Q1, the push in bushings all had a pin to hold them in place. However, sometimes they are very, very hard to see without some type of magnification because the frame was polished so well by the technican.

Hope this helps.

 

[JimGP100]

It does help thanks. I’ve looked at a few versions of the PDFs of the users manuals. The firing pin part number changes. There are versions of both the SP101 and GP100 manuals that list “KH02100” as the firing pin part.

In the push fit system, the bushings, pins, and springs were all identical (at least if ordered from Numrich).

However, companies like TKCustom note that their extended firing pin for the GP100 is not compatible with the SP101.

 

[RoninPA]

The extended FP probably is not compatible because of the way the frame is made (size) and it would probably protrude from the frame and that might lock up the cylinder and not allow it to rotate in/out of the frame.

 

[JimGP100]

Quick follow up:

Oh, as for Q1, the push in bushings all had a pin to hold them in place. However, sometimes they are very, very hard to see without some type of magnification because the frame was polished so well by the technican.

I gave an old GP100 a look. I see these faint pin circles on either side.

So, how would you get this out?

- use a punch (from either side?)

Now that that’s out, how do you get the bushing out? Try to punch the firing pin from behind? And then with the bushing out, replace the firing pin and spring and then do the reverse?

(This is all hypothetical, I’m not actually doing this as we speak, just trying to learn)

 

[RoninPA]

Pretty much as you surmised but let me look at one of mine tomorrow to be sure. The hardest part is putting it back together and getting the pin back in and aligned so it matches up with the frame so you don't have to do much to have it "disappear".

 

[JimGP100]

Cool thanks. Super helpful; I looked for where the pin might go originally—it didn’t occur how faint they might be until you mentioned it.

 

[RoninPA]

The firing pin bushing fit is very tight also and is tough to see. Open the cylinder and clean thoroughly around the firing pin and you should see the outline of the bushing. To remove the assembly I don't see any way other than to remove the pin holding the bushing and then, using a punch, tap on the firing pint to drive the ssembly out of the frame. To replace the bushing with the pin, you put the spring in the bushing, then the firing pin and then install from the front of the frame tapping it in until it is flush. You have to be careful so that you insure the cut for the pin is located correctly. Then, when you put the pin in, you want to try to get it back in the way it came out to get as close to matching the contours of the frame.

For the screw in type, from what I see, you should be able to remove the threaded part and remove the firing pin and then the spring and leave the bushing in the frame (unless it is damaged). Replace the spring and then the firing pin and screw the back part in until tight. Because of the way it is made, I would think there is a tool made that is small enough to get at the holes in the threaded part but I'm not sure. I'll have to do some research on that or maybe call Ruger and talk to a tech to see what they say.

EDIT to add: I disassembled one of my GP's and looked at the hammer channel and then cleaned it up really good and I can see a small circle (like when looking at the bushing area on the frame) and so I would modify my saying how to remove the pinned in bushing is to drive it from the back using a punch that is a bit larger than the firing pin (to contact the bushing and NOT the firing pin) to drive the bushing out the front. I still think you have to drive it back in from the front.

 

[JimGP100]

Thanks for the insights. Good find on the hammer side busing. I know what you mean about how the circle on The front is barely visible. The back is even less so! Wouldn’t be the easiest process but that’s the process I’d say.

For the screw in, I’ve seen that people grab a similar type of screwdriver bit and then modify it slightly to get the two holes.

 

[RoninPA]

Here is the only place that I found who might (or might not) still sell them. https://parts.bowenclassicarms.com/index.php?main_page=product_info&products_id=61

I think most people just modify a screwdriver to do the job.

 

[JimGP100]

Thanks again for your help