Alllen Bundy
Member
Continuing from:
My Journey From Sig P365 to P365X and Modifications Beyond
(https://www.thehighroad.org/index.p...nd-modifications-beyond.891955/#post-11996270)
P365/X/XL/SAS Grip Module Modifications
(https://www.thehighroad.org/index.php?threads/p365-x-xl-sas-grip-module-modifications.892045/)
Extending the magazine release button Sig P365/X/XL/SAS
(https://www.thehighroad.org/index.p...zine-release-button-sig-p365-x-xl-sas.892113/)
Weighting the P365/X/XL/SAS Grip Module.
https://www.thehighroad.org/index.php?threads/weighting-the-p365-x-xl-sas-grip-module.892243/
Polishing the Stripper Rail - Sig P365/X/XL/SAS
I noticed that it was very difficult to insert a magazine loaded to capacity against a closed slide in battery. In fact, I measured the magazine insertion force to be as high as 35.7 lbs. I needed to give the magazine a hard rap on the bottom to make sure that it latched into the magazine well.
Because the magazine spring forced the cartridge against the stripper rail as hard as it did, it created enough friction that it was also extremely difficult to rack the slide over a magazine loaded to capacity, and it felt very gritty while racking. The stripper rail made deep scratches into the shell cases. Another person noticed the same thing, and yet another said that he was unable to even rack the slide over a full magazine. It's not a unique problem.
For people that carry with a magazine loaded to capacity and one round in the chamber it is a concern. For people that carry with a magazine loaded to capacity, WITHOUT a round in the chamber, and need to rack the slide before firing, this is an even greater concern.
I noticed that the stripper rail was rough enough that I could feel the roughness with my fingernails. The stripper rail originally had a Nitron finish. But the underlying stainless steel stripper rail was only ground, but not polished in any way, and it was the major cause the the friction making it difficult to rack the slide. After only 49 rounds, the black finish was already wearing off of the stripper rail.
This was the only photo that I had showing the stripper rail after firing 49 rounds. The quality isn't the greatest, but you can see that the stripper rail is rough and far from being polished.
I would normally be worried about sanding through any surface nitriding that may be present. But the stripper rail surface was way too rough to be concerned with any surface finish. It should have been finished more smoothly before the Nitron finish was applied. But then again, the P365 is a high volume mass produced weapon that gives you a lot of bang for the buck and at a relatively low price. You can't expect a finely hand crafted weapon at it's selling price.
Since the stripper rail was only going to be contacting dissimilar metals, such as brass or nickel plated brass as used for shell casings, it did not have a critical need to have a nitrided stripper rail surface to prevent galling and surface wear. Brass also has a tendency to be self lubricating and it is far softer than the stainless steel stripper rail, so wear of the stripper rail isn't a huge concern. After thousands and thousands of rounds, the brass shell cases would eventually polish the stripper rail anyway. But that is a very expensive way to polish something, and I didn't want to wait that long or spend that much money on ammunition just to polish the stripper rail.
I removed the striker assembly and the striker safety, and then masked off everything but the stripper rail. I cut thin strips of wet or dry sandpaper just a wee bit wider than the stripper rail. I wet the sandpaper and used a Q-Tip to push the sandpaper back and forth along the stripper rail. The eraser end of a new pencil may also work well to push the sandpaper back and forth along the stripper rail. I started with 220 grit and worked down to 2,000 grit sandpaper, which is almost a polish. With hindsight, I'm not sure that it was necessary to sand out as much of the grinding marks as I did.
I had originally thought that the force required to rack against a closed slide, with a magazine loaded to capacity, was well beyond the range of my force gauge, so I never tried to measure it. It didn't dawn on me, until AFTER I polished the stripper rail, that I could have simply removed the recoil spring and disconnector and then independently measured the force required to overcome the racking friction, which would likely have been within the measurement range of my force gauge. So unfortunately I cannot give you any before and after measurements. Live and learn.
I do plan to buy the longer XL slide in the future and at that time I will measure the force required to rack the slide before and after polishing the stripper rail. The next time I plan to start sanding with 1,000 grit and just polish up the surface a bit and then measure the racking force. If it is anywhere near as low as the racking force of my polished P365 slide I will stop there. If the racking force is still too high I will use a coarser grit and sand the surface a little deeper, followed by finer sandpaper, then remeasure the racking force required. Hopefully I can find the optimum amount of sanding and polishing required for minimum racking friction. Some surface roughness can aid in lubrication retention, so polishing to a mirror finish is not usually required.
After cleaning everything thoroughly, including the striker chamber, I reassembled everything and lightly lubed the stripper rail with Mil Comm TW25B synthetic grease.
The sanding job made a night and day reduction in the amount of racking force required with a magazine loaded to capacity against a closed slide. The gritty feeling while racking the slide is also gone. It was well worth my time and effort to polish the stripper rail while I was listening to a podcast.
Some people will say that you should just let the stripper rail be polished by use. But can you really afford shoot the thousands and thousands of rounds of ammo just to polish the stripper rail and can you really afford to wait that long?
Some people don't want to carry with a round in the chamber. But do you have the strength to rack the slide over a magazine loaded to capacity? (Especially in a defensive situation where you could already be injured.)
People commonly carry with one round in the chamber and a magazine loaded to capacity. Let's say that you pull the trigger and the gun goes click, but no boom. You will need to rack the slide. But do you have the strength to rack the slide over a magazine loaded to capacity?
The recoil force might be enough to cycle the slide with an unpolished stripper rail under normal conditions. But polishing the stripper rail might mean the difference between your weapon cycling properly or not in a less than ideal defensive situation.
For example, if you accidentally let your thumb drag on the slide, or perhaps you dropped your pistol in the mud and you had to fire it before you could clean it, and grit worked it's way into the rails, or perhaps the cartridge had a weak load, with all of that extra stripper rail friction it might not complete the loading cycle. But if you had removed the substantial amount of resistance that the stripper rail was causing, by polishing the stripper rail, it might just allow the slide to cycle fully, even if you screwed up, and having polished the stripper rail could save your butt.
A few words of caution and common sense about polishing parts. Friction is usually lowest when dissimilar materials are contacting each other. If you have two stainless steel surfaces sliding against each other they tend to gall or result in a stick-slip chattering action. If you nitride at least one of those surfaces, it can eliminate or reduce that stick-slip chattering and/or galling. The nitrided surface may be a little rough and you may be tempted to sand it smooth. But you don't normally want to sand through this nitrided finish. Sanding off the high spots with ultra fine sandpaper may be all that is necessary, if that. You don't normally want to remove a significant amount of metal. You do not normally need to sand out every mark and scratch in the metal to make a significant reduction in friction. Just polishing the surface a bit with ultra fine sandpaper may be all that is necessary.
I prefer to carefully hand sand, which will usually result in maintaining flat surfaces. I prefer not to use power polishing tools to smooth surfaces, as they can sometimes result in uneven surfaces, which defeats the point of smoothing the surfaces.
There are some people that seem to think that you should NOT polish gun parts and that you should just let them wear in by themselves. They think that polishing parts, that were going to smooth out from use anyway, will somehow reduce the lifespan on the gun. Nothing could be further from the truth. Any time that you have rough parts, they have high spots that result in small surface contact areas that create high pressure points on metals that they are sliding against. The pressure is enormous and often high enough to exceed the film strength of the lubricant and then you have metal to metal contact and metal wear.
The high points will eventually be worn down, but not before they put scratches into the other piece of metal. Once the high spots have been worn down, the surface contact area increases dramatically and you have a much lower pressure over the surface contact area and usually low enough that it does not exceed the film strength of the lubricant anymore. At that point the wear basically stops. If you remove the high spots when the gun is new, those high spots will never be able to cause wear in the other piece of metal. This will result in LESS wear than if you let the parts wear in by themselves.
But you need to remain vigilant. Once contaminants enter the lubricant film, wear begins to occur again. Hence the importance of cleaning and re-lubricating sliding surfaces often.
In addition to polishing the stripper rail, while I already had the striker assembly removed, I polished the sides of the striker channel and the sides of the striker, as well as the sear engagement points on the striker. You do NOT want to sand through the finish on either the striker channel on the slide or the striker itself! Just give it a light wet sanding with 2,000 grit sandpaper. Don't try to sand these parts to a mirror finish. You are just trying to remove any high spots. This will help smooth out the trigger pull a little bit. I've indicated the areas to polish in the photos.
I recommend that you watch these videos below before attempting any work on the P365/X/XL/SAS.
Best way to remove a Sig P320 or P365 magazine release button
(www.youtube.com/watch?v=FZYBWC6pCdg)
How to remove new and old style P365 striker assembly
(www.youtube.com/watch?v=83hAANDK-zI)
SIG Sauer P365 COMPLETE disassembly. Part 1 of 2
(www.youtube.com/watch?v=fV4UFjgPx3Q)
SIG Sauer P365 complete reassembly. Part 2 of 2
(www.youtube.com/watch?v=tWZMzN8Nlzs)
Next: Recoil Spring Assemblies, Sig vs Rival Arms/ISMI for P365/X/SAS
My Journey From Sig P365 to P365X and Modifications Beyond
(https://www.thehighroad.org/index.p...nd-modifications-beyond.891955/#post-11996270)
P365/X/XL/SAS Grip Module Modifications
(https://www.thehighroad.org/index.php?threads/p365-x-xl-sas-grip-module-modifications.892045/)
Extending the magazine release button Sig P365/X/XL/SAS
(https://www.thehighroad.org/index.p...zine-release-button-sig-p365-x-xl-sas.892113/)
Weighting the P365/X/XL/SAS Grip Module.
https://www.thehighroad.org/index.php?threads/weighting-the-p365-x-xl-sas-grip-module.892243/
Polishing the Stripper Rail - Sig P365/X/XL/SAS
I noticed that it was very difficult to insert a magazine loaded to capacity against a closed slide in battery. In fact, I measured the magazine insertion force to be as high as 35.7 lbs. I needed to give the magazine a hard rap on the bottom to make sure that it latched into the magazine well.
Because the magazine spring forced the cartridge against the stripper rail as hard as it did, it created enough friction that it was also extremely difficult to rack the slide over a magazine loaded to capacity, and it felt very gritty while racking. The stripper rail made deep scratches into the shell cases. Another person noticed the same thing, and yet another said that he was unable to even rack the slide over a full magazine. It's not a unique problem.
For people that carry with a magazine loaded to capacity and one round in the chamber it is a concern. For people that carry with a magazine loaded to capacity, WITHOUT a round in the chamber, and need to rack the slide before firing, this is an even greater concern.
I noticed that the stripper rail was rough enough that I could feel the roughness with my fingernails. The stripper rail originally had a Nitron finish. But the underlying stainless steel stripper rail was only ground, but not polished in any way, and it was the major cause the the friction making it difficult to rack the slide. After only 49 rounds, the black finish was already wearing off of the stripper rail.
This was the only photo that I had showing the stripper rail after firing 49 rounds. The quality isn't the greatest, but you can see that the stripper rail is rough and far from being polished.
I would normally be worried about sanding through any surface nitriding that may be present. But the stripper rail surface was way too rough to be concerned with any surface finish. It should have been finished more smoothly before the Nitron finish was applied. But then again, the P365 is a high volume mass produced weapon that gives you a lot of bang for the buck and at a relatively low price. You can't expect a finely hand crafted weapon at it's selling price.
Since the stripper rail was only going to be contacting dissimilar metals, such as brass or nickel plated brass as used for shell casings, it did not have a critical need to have a nitrided stripper rail surface to prevent galling and surface wear. Brass also has a tendency to be self lubricating and it is far softer than the stainless steel stripper rail, so wear of the stripper rail isn't a huge concern. After thousands and thousands of rounds, the brass shell cases would eventually polish the stripper rail anyway. But that is a very expensive way to polish something, and I didn't want to wait that long or spend that much money on ammunition just to polish the stripper rail.
I removed the striker assembly and the striker safety, and then masked off everything but the stripper rail. I cut thin strips of wet or dry sandpaper just a wee bit wider than the stripper rail. I wet the sandpaper and used a Q-Tip to push the sandpaper back and forth along the stripper rail. The eraser end of a new pencil may also work well to push the sandpaper back and forth along the stripper rail. I started with 220 grit and worked down to 2,000 grit sandpaper, which is almost a polish. With hindsight, I'm not sure that it was necessary to sand out as much of the grinding marks as I did.
I had originally thought that the force required to rack against a closed slide, with a magazine loaded to capacity, was well beyond the range of my force gauge, so I never tried to measure it. It didn't dawn on me, until AFTER I polished the stripper rail, that I could have simply removed the recoil spring and disconnector and then independently measured the force required to overcome the racking friction, which would likely have been within the measurement range of my force gauge. So unfortunately I cannot give you any before and after measurements. Live and learn.
I do plan to buy the longer XL slide in the future and at that time I will measure the force required to rack the slide before and after polishing the stripper rail. The next time I plan to start sanding with 1,000 grit and just polish up the surface a bit and then measure the racking force. If it is anywhere near as low as the racking force of my polished P365 slide I will stop there. If the racking force is still too high I will use a coarser grit and sand the surface a little deeper, followed by finer sandpaper, then remeasure the racking force required. Hopefully I can find the optimum amount of sanding and polishing required for minimum racking friction. Some surface roughness can aid in lubrication retention, so polishing to a mirror finish is not usually required.
After cleaning everything thoroughly, including the striker chamber, I reassembled everything and lightly lubed the stripper rail with Mil Comm TW25B synthetic grease.
The sanding job made a night and day reduction in the amount of racking force required with a magazine loaded to capacity against a closed slide. The gritty feeling while racking the slide is also gone. It was well worth my time and effort to polish the stripper rail while I was listening to a podcast.
Some people will say that you should just let the stripper rail be polished by use. But can you really afford shoot the thousands and thousands of rounds of ammo just to polish the stripper rail and can you really afford to wait that long?
Some people don't want to carry with a round in the chamber. But do you have the strength to rack the slide over a magazine loaded to capacity? (Especially in a defensive situation where you could already be injured.)
People commonly carry with one round in the chamber and a magazine loaded to capacity. Let's say that you pull the trigger and the gun goes click, but no boom. You will need to rack the slide. But do you have the strength to rack the slide over a magazine loaded to capacity?
The recoil force might be enough to cycle the slide with an unpolished stripper rail under normal conditions. But polishing the stripper rail might mean the difference between your weapon cycling properly or not in a less than ideal defensive situation.
For example, if you accidentally let your thumb drag on the slide, or perhaps you dropped your pistol in the mud and you had to fire it before you could clean it, and grit worked it's way into the rails, or perhaps the cartridge had a weak load, with all of that extra stripper rail friction it might not complete the loading cycle. But if you had removed the substantial amount of resistance that the stripper rail was causing, by polishing the stripper rail, it might just allow the slide to cycle fully, even if you screwed up, and having polished the stripper rail could save your butt.
A few words of caution and common sense about polishing parts. Friction is usually lowest when dissimilar materials are contacting each other. If you have two stainless steel surfaces sliding against each other they tend to gall or result in a stick-slip chattering action. If you nitride at least one of those surfaces, it can eliminate or reduce that stick-slip chattering and/or galling. The nitrided surface may be a little rough and you may be tempted to sand it smooth. But you don't normally want to sand through this nitrided finish. Sanding off the high spots with ultra fine sandpaper may be all that is necessary, if that. You don't normally want to remove a significant amount of metal. You do not normally need to sand out every mark and scratch in the metal to make a significant reduction in friction. Just polishing the surface a bit with ultra fine sandpaper may be all that is necessary.
I prefer to carefully hand sand, which will usually result in maintaining flat surfaces. I prefer not to use power polishing tools to smooth surfaces, as they can sometimes result in uneven surfaces, which defeats the point of smoothing the surfaces.
There are some people that seem to think that you should NOT polish gun parts and that you should just let them wear in by themselves. They think that polishing parts, that were going to smooth out from use anyway, will somehow reduce the lifespan on the gun. Nothing could be further from the truth. Any time that you have rough parts, they have high spots that result in small surface contact areas that create high pressure points on metals that they are sliding against. The pressure is enormous and often high enough to exceed the film strength of the lubricant and then you have metal to metal contact and metal wear.
The high points will eventually be worn down, but not before they put scratches into the other piece of metal. Once the high spots have been worn down, the surface contact area increases dramatically and you have a much lower pressure over the surface contact area and usually low enough that it does not exceed the film strength of the lubricant anymore. At that point the wear basically stops. If you remove the high spots when the gun is new, those high spots will never be able to cause wear in the other piece of metal. This will result in LESS wear than if you let the parts wear in by themselves.
But you need to remain vigilant. Once contaminants enter the lubricant film, wear begins to occur again. Hence the importance of cleaning and re-lubricating sliding surfaces often.
In addition to polishing the stripper rail, while I already had the striker assembly removed, I polished the sides of the striker channel and the sides of the striker, as well as the sear engagement points on the striker. You do NOT want to sand through the finish on either the striker channel on the slide or the striker itself! Just give it a light wet sanding with 2,000 grit sandpaper. Don't try to sand these parts to a mirror finish. You are just trying to remove any high spots. This will help smooth out the trigger pull a little bit. I've indicated the areas to polish in the photos.
I recommend that you watch these videos below before attempting any work on the P365/X/XL/SAS.
Best way to remove a Sig P320 or P365 magazine release button
(www.youtube.com/watch?v=FZYBWC6pCdg)
How to remove new and old style P365 striker assembly
(www.youtube.com/watch?v=83hAANDK-zI)
SIG Sauer P365 COMPLETE disassembly. Part 1 of 2
(www.youtube.com/watch?v=fV4UFjgPx3Q)
SIG Sauer P365 complete reassembly. Part 2 of 2
(www.youtube.com/watch?v=tWZMzN8Nlzs)
Next: Recoil Spring Assemblies, Sig vs Rival Arms/ISMI for P365/X/SAS
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