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Discussion Starter · #1 ·
I removed the retainer pin from the bolt head and can't get the firing pin free (Note: First time I've tried to remove the firing pin). It backs out about 1/4", but then seems to have some resistance and don't want to pry/force it without some better idea of what is going on. Tried to rotate the pin a few degrees -- all the way though 360, but still does not release from the bolt head. No failures to fire up to this point.

Read the owner's and armorer's guides, and can't find anything I've missed.

Anyone have suggestions on how to attack this issue?
 

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...you removed the retaining pin going through the "bolt shaft"...right...???...the "entire" pin it out now...it didn't break in half...or anything like that...

...take a brass punch or anything kinda soft...mabey a pen or cut down piece of wood...and "very" lightly tap the tip of the firing pin...while the bolt shaft is pointing away from you...add a few drops of CLP before you do this...it might help...
 

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Discussion Starter · #3 ·
Ullie,

Thanks for the advice!, That partially got it past the sticking point -- enough to finally coax it out with pliers after wrapping the base of the pin with a scrap of cloth.

Here's what I think was the root cause:

The front of the firing pin spring registers on a tapered part of the firing pin, as opposed to a flat base at the tail of the pin. The spring had ridden up on the taper and spread out enough to cause a bind in the bolt head. Also found a serious burr on that end of the spring. I corrected the burr with careful use of a needle file and that seems to have fixed it.

Should anyone else have similar issue, I suggest rotating the pin with pliers in a clockwise direction as you are face the rear of the bolt head. If the problem is a burr on the spring, this will keep the burr from digging in and galling the inside of the bolt head.
 

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I can't even get the retaining pin to budge through the bolt head. Tapping, pushing. Will not move an millimeter. Any suggestions?
 

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I'd soak it for a long time in hoppe's then after it was swimming in breakfree for an hour I'd go at it with one of my monitor adjustment tools (it's plastic and small enough to ride right through the bolt). Or I'd go with something like a bamboo skewer. From cleaning my rifle, I have to say the firing pin retention is the thing I hate most about it. And one thing I'll be sure to clean every time I shoot, even though it's a pita.
 

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KuroNeko said:
I'd soak it for a long time in hoppe's then after it was swimming in breakfree for an hour I'd go at it with one of my monitor adjustment tools (it's plastic and small enough to ride right through the bolt). Or I'd go with something like a bamboo skewer. From cleaning my rifle, I have to say the firing pin retention is the thing I hate most about it. And one thing I'll be sure to clean every time I shoot, even though it's a pita.
Thanks. I'll try it. But I somehow don't think it's gonna work. That retaining pin WILL NOT BUDGE ONE MILLIMETER. I've been pushing on that thing for the last hour and it just won't move. It really shouldn't be in there that tightly, correct? I'm a pretty big guy and I've been exerting all my force to push that pin out.
 

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bonehead said:
Thanks. I'll try it. But I somehow don't think it's gonna work. That retaining pin WILL NOT BUDGE ONE MILLIMETER. I've been pushing on that thing for the last hour and it just won't move. It really shouldn't be in there that tightly, correct? I'm a pretty big guy and I've been exerting all my force to push that pin out.
If you've fired it and not cleaned it each time, it's possible. I soaked the bolt in breakfree while I cleaned the rest of the rifle and when I got the pin out, lucky I was on a tile floor cause it went flying and rolling under the table... Once I got all the grease and fouling from the test fires out, it and the pin/spring go in an out easily as long as it's all lined up. Even if I just wipe out the gunk from firing etc, I'll do a thorough job on the bolt and spring every time :/
 

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bonehead said:
I can't even get the retaining pin to budge through the bolt head. Tapping, pushing. Will not move an millimeter. Any suggestions?
You are relieving the tension off of the pin by compressing the spring, right?
 

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Apocalypto said:
bonehead said:
I can't even get the retaining pin to budge through the bolt head. Tapping, pushing. Will not move an millimeter. Any suggestions?
You are relieving the tension off of the pin by compressing the spring, right?
Pushing the tip of the firing pin against the table, then trying to push the retaining pin through the bolt. Nothing.
 

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Any other ideas? This is extremely frustrating. The only thing left to clean/lubricate so I can put this thing back together and shoot tomorrow! :x
 

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It must just be really gummed up, or maybe they were made to max tolerances and are just that tight. Mine comes out with minimal effort, but I had a film of breakfree on everything prior to ever firing it. Good luck.
 

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Oh, this just hit me.... stick it in the freezer for a few hours as it soaks, then see if you can budge it. Works for dead hdd's so might work for metal rifle parts ^^v
 

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KuroNeko said:
Oh, this just hit me.... stick it in the freezer for a few hours as it soaks, then see if you can budge it. Works for dead hdd's so might work for metal rifle parts ^^v
Cold will make the metal contract. Add heat and maybe it will expand enough to release, use maybe a blowdryer.

Actually this depends on which metal has to larger coefficient of expansion. It could go either way (hot or cold)
 

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The only other thing I could think of is using a big vise or bar clamp to compress the firing pin and tap it with a punch and mallet. You could just clean it out with clp and canned air, and try it when it's hot after firing.

And on fourth thought, I'd call sig before I took a mallet to the retaining pin just to see what they say. I suppose it might be possible the firing pin is rotated slightly in the bolt? I have no clue on the tolerances inside the bolt, but I'd want to know before I potentially damaged the firing pin.. :/.
 

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KuroNeko said:
The only other thing I could think of is using a big vise or bar clamp to compress the firing pin and tap it with a punch and mallet. You could just clean it out with clp and canned air, and try it when it's hot after firing.

And on fourth thought, I'd call sig before I took a mallet to the retaining pin just to see what they say. I suppose it might be possible the firing pin is rotated slightly in the bolt? I have no clue on the tolerances inside the bolt, but I'd want to know before I potentially damaged the firing pin.. :/.
I'm debating on whether or not I should just fire it tomorrow without having taken out the firing pin and cleaning/lubricating the spring/pin assembly. Part of me says this is a bad idea; if a piece doesn't work properly, don't shoot the gun. On the otherhand, as you said, getting the gun a bit hot may be all I need to jar that stupid thing loose.

What say ye?
 

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The whole thing as I see it, is, the retaining pin is doing it's job, to keep the firing pin in place. If the firing pin isn't binding, then its working as it should, it's just the retention pin is 'stuck'.

The thing I'd do is clean it out with something like hoppe's or other thin solvent, and really squirt it in every crevice with a modeler's syringe. Then drain it, and blow out the excess with canned air, then compress it and listen for sounds of binding or other improper function. It should move freely and not make any kind of clicking or other odd noises (this is of course beyond the spring's own odd compression sound). If it moves freely and isn't obviously caught on anything, I'd lube it with some breakfree and shoot it, then be ready to break it down at the range while it's hot/warm. Just don't loose the pin if it goes popping out at high speed heh.

This of course is my own humble opinion and in no way [insert proper legaleze here] means you should fire a broken weapon, but I think if it's clearly working as designed and you just have some badly caked in fouling or the tolerances are a bit too tight, it would be fine to shoot. And if you can't free the pin when the whole thing has been heated and shaken by firing, then you'd probably be best to go the more careful route and talk to a gunsmith and/or Sig.
 

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KuroNeko said:
The whole thing as I see it, is, the retaining pin is doing it's job, to keep the firing pin in place. If the firing pin isn't binding, then its working as it should, it's just the retention pin is 'stuck'.

The thing I'd do is clean it out with something like hoppe's or other thin solvent, and really squirt it in every crevice with a modeler's syringe. Then drain it, and blow out the excess with canned air, then compress it and listen for sounds of binding or other improper function. It should move freely and not make any kind of clicking or other odd noises (this is of course beyond the spring's own odd compression sound). If it moves freely and isn't obviously caught on anything, I'd lube it with some breakfree and shoot it, then be ready to break it down at the range while it's hot/warm. Just don't loose the pin if it goes popping out at high speed heh.

This of course is my own humble opinion and in no way [insert proper legaleze here] means you should fire a broken weapon, but I think if it's clearly working as designed and you just have some badly caked in fouling or the tolerances are a bit too tight, it would be fine to shoot. And if you can't free the pin when the whole thing has been heated and shaken by firing, then you'd probably be best to go the more careful route and talk to a gunsmith and/or Sig.
Thank you again for your input. I've been thinking the same thing. Just irks me that I can't remove the darn pin. That and struggling to remove the silly front pivot screw (which I have promptly replaced with the KNS pivot pin), has made for one bad experience thus far. And I haven't even shot it yet!
 

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bonehead said:
Thank you again for your input. I've been thinking the same thing. Just irks me that I can't remove the darn pin. That and struggling to remove the silly front pivot screw (which I have promptly replaced with the KNS pivot pin), has made for one bad experience thus far. And I haven't even shot it yet!
You're welcome. I've not shot mine either yet, and the firing pin maintenance... oooooh..... If you've not shot it yet, just hit it with hoppe's to clear out the grease and fouling left over from the test firing, and it should be fine to shoot.

If you break it down at the range, make sure to cup your hand over the other end so the pin won't go flying 3 feet like mine did when it came free the first time. And getting the pin back in, is trickier than getting it out imho.... I use a plastic tool that's the same diameter almost as the retention hole, and I stick that in and wiggle the pin proper before I seat the pin, if I see even a sliver of silver it won't re-seat.

I wouldn't look at it as a bad experience personally though. It's just new and tight, and that's good ;3 I'd be much more concerned if things were wobbly and rattled and 'too easy' to do.
 
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