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
(https://www.thehighroad.org/index.php?threads/polishing-the-stripper-rail-sig-p365-x-xl-sas.892413/P
Recoil Spring Assemblies, Sig vs Rival Arms/ISMI for P365/X/SAS
I was a little concerned when I found out that that Sig recommends the replacement of their recoil spring assembly after only 2,500 rounds, which seems like an awfully low spring lifespan. It appears that Sig is using a spring that is NOT heat treated and stress relieved AFTER forming. But worse still, I discovered that there is a failure mode where the recoil spring can coil over itself and cause the P365/X/XL/SAS to jam after as little as 200 rounds. I know of at least 6 cases of this defect happening.
ISMI makes a recoil spring that IS heat treated, shot peened and stress relived AFTER forming, which produces a longer lasting and more reliable spring. It is also a flat coil design which virtually eliminates the possibility of the spring coiling over itself. I am presently testing a Rival Arms guide rod with an ISMI recoil spring to replace the stock Sig RSA. I fired 6 different 115 gr 9mm cartridge brands/models with a total of 162 rounds without a hiccup. I didn't notice any difference between the stock Sig recoil spring assembly and the Rival Arms recoil spring assembly while shooting.
I did notice when comparing the stock double spring Sig RSA to the single spring Rival Arms/ISMI RSA, the Sig RSA could more easily pull the slide closed under adverse conditions. The Sig dual recoil spring assembly appears to have more spring preload than the Rival Arms/ISMI spring. After a short break-in period, the force required to rack the slide, with either the Sig or the Rival Arms RSA, was about 76 Newtons, which works out to be almost 17 lbs on the nose, which is what the recoil spring force is supposed to be. When the RSAs were new the spring force was about 1 lb more. FYI, I removed the disconnector to eliminate any friction that could cause measurement errors.
HOWEVER, the Rival Arms RSA is not without it's own problems. Unfortunately, contrary to it's claims of having an "Ultra Smooth" guide rod, it was very rough, still having the lathe turning marks on the guide rod, which makes racking the slide sound like dragging your fingernails across the grooves of a phonograph record. It very disconcerting and makes you think that there is something seriously wrong when you rack the slide.
I talked with Rival Arms and the guy claimed that the guide rod was supposed to be very smooth. They had me send them the RSA for exchange. The next RSA that I received was just as rough as the one I sent back. After a number of e-mails back and forth, someone finally admitted that they didn't polish their guide rod and just turned the guide rod on a lathe, as if that was supposed to be "Ultra Smooth" as advertised.
They said: "Hopefully after a good break-in period, several 1000 rounds, the rough sound will diminish."
I made a spring compressing fixture to compress the recoil spring so that I could have access to the recoil spring retaining bolt. I clamped a vice grips, with a leather pad on the jaws, to the flange on the end of the guide rod. While I was adjusting the second vice grips to clamp over the retaining bolt, the bolt turned! Rival Arms had used a red threadlocker on the bolt threads which is usually a high strength threadlocker. When cured properly, the red threadlocker is normally so strong that you will often snap off the head of a bolt if you try to unscrew the bolt without first heating the bolt to 450°F for 5 minutes. The threadlocker had NOT cured properly.
FYI, another person online had mentioned that the recoil spring retainer bolt on his Rival Arms RSA also came loose and that he had to reapply a threadlocker to the bolt.
The Rival Arms guide rod is stainless steel and the recoil spring retaining bolt is oxide coated steel. These metals will not usually activate the threadlocker, and you need to apply a primer to the threads to get the threadlocker to cure. I would say that it is likely that Rival Arms is NOT using a primer on the guide rod and bolt threads. It's a common mistake. I notified Rival Arms about the issue with the threadlocker not properly curing so hopefully they will correct the problem.
I then wet sanded the guide rod starting with 400 grit and working down to 2,000 grit sandpaper.
Here are the before and after photos:
The spring compressor that I made:
Top: Unpolished - Bottom: Wet Sanded to 2,000 grit.
Top: Unpolished - Bottom: Wet Sanded to 2,000 grit.
Top: Guide Rod After Wet Sanding to 2,000 Grit:
Bottom: Assembled Rival Arms/ISMI RSA After Polishing
I cleaned the guide rod threads with 99.9% isopropyl alcohol. I applied medium strength blue Loctite 243, with the primer already inside. It set up very quickly. I tested it at the range with 162 rounds and the recoil spring retainer bolt has not come loose. I compressed the recoil spring again and used a leather pad on each end of the guide rod for more traction and tried to turn the recoil spring retainer screw by the head. Try as I might, I could not turn it. I do not think that it's possible to generate enough torsional force to break the Loctite loose while the RSA is in use.
I believe that medium strength blue Loctite 243, with primer applied, is more than adequate for this application. But I think that Rival Arms doesn't want you to take their RSA apart so that is why they use the high strength red threadlocker.
It's best if the threads are free of oil. Oil on the threads will slow down the cure time and reduce the strength. Always solvent clean the threads before applying Loctite.
Loctite IS anaerobic. But in addition to a lack of oxygen, it also needs the presence of certain metal ions before it will cure.
Active Metals (Primers Optional)
Iron, Plain Steel, Copper, Brass, Bronze, Manganese, Monel, Kovar
Inactive Metals (Primers Recommended)
Plated Parts, Anodized Aluminum, Titanium, Stainless Steel, Galvanized Steel, Zinc, Pure Aluminum, Cadmium, Magnesium, Natural or Chemical Black Oxide, Magnetite Steel, Inconel, Silver, Gold
Threadlocking User’s Guide:
https://dm.henkel-dam.com/is/content/henkel/MRO_TL_Guide
More often than not, at least one thread surface is made of an active metal that will activate the Loctite to cure. But there are still plenty of occasions when both thread surfaces are made from inactive metals, and a primer is necessary to activate the Loctite so it will cure. Loctite now makes a few new formulations that contain primer so that you do not need to apply the primer separately.
---------------------------------
Stock Sig RSA:
The Pros:
It's cheaper.
It has a higher spring preload force so it will better be able to close the slide when the breach face is dirty.
The Cons:
Shorter lifespan
Possible failure mode of the recoil spring coiling over itself and jamming at low round counts.
Rival Arms/ISMI RSA:
The Pros:
More than double the lifespan of the Sig RSA.
It's recoil spring is virtually unable to coil over itself by design.
The Cons:
More Expensive.
As it comes out of the box, the guide rod is rough and very noisy when you rack the slide.
The recoil spring retainer bolt may come loose because of the threadlocker not being properly cured.
----------------------------------------
I would NOT recommend using the Rival Arms/ISMI RSA until you disassemble it, polish the guide rod, clean the threads, apply primer to the threads, or use a Loctite formulation with the primer already inside.
Would I ever buy a Rival Arms RSA again? Yes, without hesitation. But I would do so with the knowledge that I would disassemble it, polish the guide rod, apply Loctite to the threads and screw it back together before I used it. Is it reasonable that I should need to rebuild the Rival Arms RSA before using it? No. But that has often been my experience with aftermarket parts of many types. It's not that big of a deal to do some finishing work on parts before use. I could have polished the guide rod and rebuilt the Rival Arms RSA in less time than it took to write about it. If it helps me achieve my goals I'm willing to go through a little extra work.
All things considered I believe that the Rival Arms/ISMI RSA has less chance of a catastrophic failure than the stock Sig RSA in a defensive situation. For carry, I'll use the Rival Arms RSA with a low round count. But I'll use the Sig RSA for target practice until it breaks and/or the slide fails to cycle properly.
Next: Failure to Return To Battery Prevention - P365/X/XL/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
(https://www.thehighroad.org/index.php?threads/polishing-the-stripper-rail-sig-p365-x-xl-sas.892413/P
Recoil Spring Assemblies, Sig vs Rival Arms/ISMI for P365/X/SAS
I was a little concerned when I found out that that Sig recommends the replacement of their recoil spring assembly after only 2,500 rounds, which seems like an awfully low spring lifespan. It appears that Sig is using a spring that is NOT heat treated and stress relieved AFTER forming. But worse still, I discovered that there is a failure mode where the recoil spring can coil over itself and cause the P365/X/XL/SAS to jam after as little as 200 rounds. I know of at least 6 cases of this defect happening.
ISMI makes a recoil spring that IS heat treated, shot peened and stress relived AFTER forming, which produces a longer lasting and more reliable spring. It is also a flat coil design which virtually eliminates the possibility of the spring coiling over itself. I am presently testing a Rival Arms guide rod with an ISMI recoil spring to replace the stock Sig RSA. I fired 6 different 115 gr 9mm cartridge brands/models with a total of 162 rounds without a hiccup. I didn't notice any difference between the stock Sig recoil spring assembly and the Rival Arms recoil spring assembly while shooting.
I did notice when comparing the stock double spring Sig RSA to the single spring Rival Arms/ISMI RSA, the Sig RSA could more easily pull the slide closed under adverse conditions. The Sig dual recoil spring assembly appears to have more spring preload than the Rival Arms/ISMI spring. After a short break-in period, the force required to rack the slide, with either the Sig or the Rival Arms RSA, was about 76 Newtons, which works out to be almost 17 lbs on the nose, which is what the recoil spring force is supposed to be. When the RSAs were new the spring force was about 1 lb more. FYI, I removed the disconnector to eliminate any friction that could cause measurement errors.
HOWEVER, the Rival Arms RSA is not without it's own problems. Unfortunately, contrary to it's claims of having an "Ultra Smooth" guide rod, it was very rough, still having the lathe turning marks on the guide rod, which makes racking the slide sound like dragging your fingernails across the grooves of a phonograph record. It very disconcerting and makes you think that there is something seriously wrong when you rack the slide.
I talked with Rival Arms and the guy claimed that the guide rod was supposed to be very smooth. They had me send them the RSA for exchange. The next RSA that I received was just as rough as the one I sent back. After a number of e-mails back and forth, someone finally admitted that they didn't polish their guide rod and just turned the guide rod on a lathe, as if that was supposed to be "Ultra Smooth" as advertised.
They said: "Hopefully after a good break-in period, several 1000 rounds, the rough sound will diminish."
I made a spring compressing fixture to compress the recoil spring so that I could have access to the recoil spring retaining bolt. I clamped a vice grips, with a leather pad on the jaws, to the flange on the end of the guide rod. While I was adjusting the second vice grips to clamp over the retaining bolt, the bolt turned! Rival Arms had used a red threadlocker on the bolt threads which is usually a high strength threadlocker. When cured properly, the red threadlocker is normally so strong that you will often snap off the head of a bolt if you try to unscrew the bolt without first heating the bolt to 450°F for 5 minutes. The threadlocker had NOT cured properly.
FYI, another person online had mentioned that the recoil spring retainer bolt on his Rival Arms RSA also came loose and that he had to reapply a threadlocker to the bolt.
The Rival Arms guide rod is stainless steel and the recoil spring retaining bolt is oxide coated steel. These metals will not usually activate the threadlocker, and you need to apply a primer to the threads to get the threadlocker to cure. I would say that it is likely that Rival Arms is NOT using a primer on the guide rod and bolt threads. It's a common mistake. I notified Rival Arms about the issue with the threadlocker not properly curing so hopefully they will correct the problem.
I then wet sanded the guide rod starting with 400 grit and working down to 2,000 grit sandpaper.
Here are the before and after photos:
The spring compressor that I made:
Top: Unpolished - Bottom: Wet Sanded to 2,000 grit.
Top: Unpolished - Bottom: Wet Sanded to 2,000 grit.
Top: Guide Rod After Wet Sanding to 2,000 Grit:
Bottom: Assembled Rival Arms/ISMI RSA After Polishing
I cleaned the guide rod threads with 99.9% isopropyl alcohol. I applied medium strength blue Loctite 243, with the primer already inside. It set up very quickly. I tested it at the range with 162 rounds and the recoil spring retainer bolt has not come loose. I compressed the recoil spring again and used a leather pad on each end of the guide rod for more traction and tried to turn the recoil spring retainer screw by the head. Try as I might, I could not turn it. I do not think that it's possible to generate enough torsional force to break the Loctite loose while the RSA is in use.
I believe that medium strength blue Loctite 243, with primer applied, is more than adequate for this application. But I think that Rival Arms doesn't want you to take their RSA apart so that is why they use the high strength red threadlocker.
It's best if the threads are free of oil. Oil on the threads will slow down the cure time and reduce the strength. Always solvent clean the threads before applying Loctite.
Loctite IS anaerobic. But in addition to a lack of oxygen, it also needs the presence of certain metal ions before it will cure.
Active Metals (Primers Optional)
Iron, Plain Steel, Copper, Brass, Bronze, Manganese, Monel, Kovar
Inactive Metals (Primers Recommended)
Plated Parts, Anodized Aluminum, Titanium, Stainless Steel, Galvanized Steel, Zinc, Pure Aluminum, Cadmium, Magnesium, Natural or Chemical Black Oxide, Magnetite Steel, Inconel, Silver, Gold
Threadlocking User’s Guide:
https://dm.henkel-dam.com/is/content/henkel/MRO_TL_Guide
More often than not, at least one thread surface is made of an active metal that will activate the Loctite to cure. But there are still plenty of occasions when both thread surfaces are made from inactive metals, and a primer is necessary to activate the Loctite so it will cure. Loctite now makes a few new formulations that contain primer so that you do not need to apply the primer separately.
---------------------------------
Stock Sig RSA:
The Pros:
It's cheaper.
It has a higher spring preload force so it will better be able to close the slide when the breach face is dirty.
The Cons:
Shorter lifespan
Possible failure mode of the recoil spring coiling over itself and jamming at low round counts.
Rival Arms/ISMI RSA:
The Pros:
More than double the lifespan of the Sig RSA.
It's recoil spring is virtually unable to coil over itself by design.
The Cons:
More Expensive.
As it comes out of the box, the guide rod is rough and very noisy when you rack the slide.
The recoil spring retainer bolt may come loose because of the threadlocker not being properly cured.
----------------------------------------
I would NOT recommend using the Rival Arms/ISMI RSA until you disassemble it, polish the guide rod, clean the threads, apply primer to the threads, or use a Loctite formulation with the primer already inside.
Would I ever buy a Rival Arms RSA again? Yes, without hesitation. But I would do so with the knowledge that I would disassemble it, polish the guide rod, apply Loctite to the threads and screw it back together before I used it. Is it reasonable that I should need to rebuild the Rival Arms RSA before using it? No. But that has often been my experience with aftermarket parts of many types. It's not that big of a deal to do some finishing work on parts before use. I could have polished the guide rod and rebuilt the Rival Arms RSA in less time than it took to write about it. If it helps me achieve my goals I'm willing to go through a little extra work.
All things considered I believe that the Rival Arms/ISMI RSA has less chance of a catastrophic failure than the stock Sig RSA in a defensive situation. For carry, I'll use the Rival Arms RSA with a low round count. But I'll use the Sig RSA for target practice until it breaks and/or the slide fails to cycle properly.
Next: Failure to Return To Battery Prevention - P365/X/XL/SAS
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