It should take very little pressure to move the firing pin block.
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Question about P938 Firing Pin Block.
Every time I have cleaned my firearms, I've always just cleaned around it. This past time, I let the clp soak on the slide for a little longer than normal, and really cleaned around the firing pin block with a qtip. I noticed it was so clean it was extremely easy to depress the spring for the firing pin block. Previous times I had cleaned, it basically seemed stuck stationary. Is it normal for it to move so freely, was it just gunked up previously?
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The firing pin holds the block in place. When you ask about movement previously unseen, is this movement in the firing pin or the block unseen before?
The block. I just never noticed how easy it can be depressed before. Maybe it's because it's a little stiffer on my other firearm. I was just curious.
The ejector pushes up against it to lock the firing pin. As you pull the trigger, the ejector moves forward slightly, releasing the block and freeing the firing pin. Could create some concerns if it gets jammed, it's a good idea to make sure it does move freely every time you clean or inspect the P938.
You are speaking of the firing pin block (the plate that holds the firing pin and firing pin spring in the slide, and not the firing pin lock (that prevents the pin from impacting the round if the trigger isn't pulled), correct?
If so, the firing pin under rearward pressure from the firing pin spring, holds the block in place. The firing pin acts like a detent preventing the block from sliding down and out of the two vertical grooves in the back of the slide. The block fits rather loosely in those grooves so some movement would be normal.
Be careful not to let much cleaner seep into the firing pin channel in the slide as, over time, the buildup could restrict the firing pin movement and prevent firing.
It's fairly easy to remove the block, firing pin and firing pin spring. Use a blunt pointed object slightly smaller in diameter than the firing pin to depress the firing pin. Start to slide the block down and remove the tool. Place your finger over the rear of the slide to catch the firing pin (which will shoot out) and slide the block out of the slide.
If so, the firing pin under rearward pressure from the firing pin spring, holds the block in place. The firing pin acts like a detent preventing the block from sliding down and out of the two vertical grooves in the back of the slide. The block fits rather loosely in those grooves so some movement would be normal.
Be careful not to let much cleaner seep into the firing pin channel in the slide as, over time, the buildup could restrict the firing pin movement and prevent firing.
It's fairly easy to remove the block, firing pin and firing pin spring. Use a blunt pointed object slightly smaller in diameter than the firing pin to depress the firing pin. Start to slide the block down and remove the tool. Place your finger over the rear of the slide to catch the firing pin (which will shoot out) and slide the block out of the slide.
2
The P938 naming conventions are a little bit skewed.
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You are speaking of the firing pin block (the plate that holds the firing pin and firing pin spring in the slide, and not the firing pin lock (that prevents the pin from impacting the round if the trigger isn't pulled), correct?
I stand corrected. I was incorrectly referring to the firing pin stop as the block.
My initial thoughts as well!
Thank you both for the information. And yeah I didn't let too much get down in there, mainly just let a thin layer soak on the underside of the slide, letting a little bit seep in to the block. It just seems to make a big difference on movement when lubricating it. Even if the "dirty" firearm has only had a few hundred through it.
dtanner2 - From experience with the 938 I can tell you to keep it clean and dry in the tunnel as well as the firing pin and spring. For me at least it caused a noticeable amount of failure to fires when I put a drop of CLP down there thinking I was doing good.
So if it is easy to press the firing pin block its good to go and if it is hard to you probably have gunk in it? Because the firing pin block is the part where you don't want any oil because it can cause light primer strikes right? Or is that the striker channel?
The block and firing pin both need to move freely, for different but inter-related reasons.
ETA: Sorry about the brief answer, I'll give a bit more detail now that I'm at a keyboard. You want to keep both the firing pin block and the firing pin/firing pin channel relatively free of oil. Oil will attract dirt and debris, which will adversely impact the proper function of these items. When the slide is closed and the firearm is ready to fire, the ejector is pressing up on the firing pin block. The firing pin block in this upward position is preventing the firing pin from traveling forward enough to poke out the end of the channel and strike the primer, sparking the load in the chamber. As you start to pull the trigger, the ejector moves forward just a bit, releasing the firing pin block, allowing it to be pressed downward by the spring behind it, freeing up the firing pin to move forward to strike the primer as the hammer hits it. If the movement of the firing pin block movement is restricted by a build up of debris, you could have one of two undesirable conditions: 1) the firing pin block is locked in the upward position, preventing the firing pin from traveling forward when needed, or; 2) the firing pin block could be frozen in the bottomed out position, allowing the firing pin to travel freely, and if the firearm is dropped, could potentially ignite the round in the chamber. The other component under discussion, the firing pin and firing pin channel, if clogged with debris, could inhibit the forward motion of the firing pin enough to cause a light primer strike, or, if clogged bad enough, prevent the movement of firing pin completely. None of these conditions would be desirable, and can be prevented by keeping oil from seeping into the channels in discussion. I hope this clarifies the concern we need to be aware of.
ETA: Sorry about the brief answer, I'll give a bit more detail now that I'm at a keyboard. You want to keep both the firing pin block and the firing pin/firing pin channel relatively free of oil. Oil will attract dirt and debris, which will adversely impact the proper function of these items. When the slide is closed and the firearm is ready to fire, the ejector is pressing up on the firing pin block. The firing pin block in this upward position is preventing the firing pin from traveling forward enough to poke out the end of the channel and strike the primer, sparking the load in the chamber. As you start to pull the trigger, the ejector moves forward just a bit, releasing the firing pin block, allowing it to be pressed downward by the spring behind it, freeing up the firing pin to move forward to strike the primer as the hammer hits it. If the movement of the firing pin block movement is restricted by a build up of debris, you could have one of two undesirable conditions: 1) the firing pin block is locked in the upward position, preventing the firing pin from traveling forward when needed, or; 2) the firing pin block could be frozen in the bottomed out position, allowing the firing pin to travel freely, and if the firearm is dropped, could potentially ignite the round in the chamber. The other component under discussion, the firing pin and firing pin channel, if clogged with debris, could inhibit the forward motion of the firing pin enough to cause a light primer strike, or, if clogged bad enough, prevent the movement of firing pin completely. None of these conditions would be desirable, and can be prevented by keeping oil from seeping into the channels in discussion. I hope this clarifies the concern we need to be aware of.
Sig had cautioned me to only use a very light coat of oil on the firing pin and in the firing pin channel to help prevent powder residue from building up. They also changed the firing pin spring for me after I had fired about a 1,000 rounds, they said it was weak.
Thanks for the information guys, and thanks for this detailed response. I definitely didn't put a crazy amount of lubricant in there, but I oiled underside of the slide and made sure to clean around the block with a qtip. I know it's bad for excess oil to get in there, but figured a tiny bit around the block wouldn't hurt since it always seems to not move as freely as after a little lubricant around it. Plus I like it to depress easily with a qtip so I can get the gunk around it. I did the steps mentioned a few posts above and removed the firing pin as well, just curious as to if there was any lubricant on it, and there was not. I will keep this in mind though, but for the most part it seems from the response, that it's perfectly normal for the block to move easily, and if it's stuck is when it's a problem (which looking back I have encountered before, or at least it was hard to depress).The block and firing pin both need to move freely, for different but inter-related reasons.
ETA: Sorry about the brief answer, I'll give a bit more detail now that I'm at a keyboard. You want to keep both the firing pin block and the firing pin/firing pin channel relatively free of oil. Oil will attract dirt and debris, which will adversely impact the proper function of these items. When the slide is closed and the firearm is ready to fire, the ejector is pressing up on the firing pin block. The firing pin block in this upward position is preventing the firing pin from traveling forward enough to poke out the end of the channel and strike the primer, sparking the load in the chamber. As you start to pull the trigger, the ejector moves forward just a bit, releasing the firing pin block, allowing it to be pressed downward by the spring behind it, freeing up the firing pin to move forward to strike the primer as the hammer hits it. If the movement of the firing pin block movement is restricted by a build up of debris, you could have one of two undesirable conditions: 1) the firing pin block is locked in the upward position, preventing the firing pin from traveling forward when needed, or; 2) the firing pin block could be frozen in the bottomed out position, allowing the firing pin to travel freely, and if the firearm is dropped, could potentially ignite the round in the chamber. The other component under discussion, the firing pin and firing pin channel, if clogged with debris, could inhibit the forward motion of the firing pin enough to cause a light primer strike, or, if clogged bad enough, prevent the movement of firing pin completely. None of these conditions would be desirable, and can be prevented by keeping oil from seeping into the channels in discussion. I hope this clarifies the concern we need to be aware of.
Good to know. Mine was basically dry, so obviously what I'm doing is not going to cause enough excess oil in that channel for there to be an issue.Sig had cautioned me to only use a very light coat of oil on the firing pin and in the firing pin channel to help prevent powder residue from building up. They also changed the firing pin spring for me after I had fired about a 1,000 rounds, they said it was weak.
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