My P320 Full Size .357 SIG is approaching 10,000 rounds. I called SIG customer service to order a spare recoil spring since they are not in the store. The customer service representative I talked to said that the spring and the guide rod are sold separately. My spring is captured on the guide rod, and I can't see how it comes apart.

Am I missing something or was the customer service rep wrong?

I would order Gray Gun's rod that uses 1911 springs, but it appears they recommend them only for 9 mm.

Dunno nuthin' about P320's, but one of my Beretta's has a captured recoil spring and the guide rod and spring are sold separately.

The guide rod is three pieces, but snaps together once the spring is in place never to come apart again unless you cut or break it.

My 2015 P320 FS .40 has a captive spring as well. Could be that they replaced the captive with separate, given the following:

https://www.sigsauer.com/wp-co...ads/2016/07/P320.pdf

Page 62 of the Sig P320 Manual. Pics look like Compact/Sub-Compact have captive and FS looks like a separate rod/spring, even though they say "assembly".

EDITED: After checking my own FS recoil spring assembly, I can't tell from the pic in the manual whether it's captive or not. It's the angle. I'd call Sig CS and see if they know what's going on.

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I do have a GGI FAT rod that was designed for the 9 mm. I bought Wolff 17, 18,5 and 20# RS for it. Functions well (100%) with all three weights. The weights are close to P226 .40 and GM .40 1911's. DO NOT use the 9 mm RS for .40/.357 as it is way too light. I generally use the 17# at the range.

I use it with mid-range reloads, NOT factory. GGI considered the 9 mm factory pistols to be "oversprung" for competition purposes, which is why they developed theirs to provide less muzzle rise. This is not the case with the factory .40 RS.

GGI has done no testing with anything other than the 9 mm, so you are on your own if you choose to use it in .40/.357.

This message has been edited. Last edited by: Nipper,

 
I looked at mine, too, and I bet it comes apart. One end has a "hole" in it, like a tool could fit into, and the other end has two flats. I bet the captive parts screw together.
 
If so, it would be similar to my P220-10mm, which is also captive. I learned about how it goes together when it came apart during disassembly for cleaning. Spring itself aside, there are 3 pieces, the longer "solid" piece with two holes in the end (for some tool). Then a hollow piece that the "solid" one slides through. And looking carefully there is a tiny cap screw that threads into the long "solid" piece to bring it together. I put solid in quotes because it is not, completely solid. There is a threaded hole in one end to receive the little cap screw.
 

Wow. How does your 320 look, after all those rounds? By chance, any pictures you can post?

So, the customer service guy said he screwed up and should have sold me an assembly instead of just a spring. He is going to send me one for free, but they don't have them in stock. I guess SIG didn't expect us to actually shoot the pistols we bought.

I asked him for the part number so I could hopefully avoid confusion on future orders and he told me it is RSA-320F-9. This doesn't sound right to me since the "-9" would seem to indicate 9mm and not .357 SIG. I asked him if he was sure that was the correct number and he said it was.

Is there a good way to test it once I get it? How would I know if it was too light, and could it damage anything if I shoot it and it is too light?

I received my Gray Guns guide rod about a week ago and was just about to order some Wolff springs when I got a notice from SIG stating that my recoil spring assembly had shipped and should be here Tuesday. It is interesting to note that the part number noted is RSA-320F-4035745 and not RSA-320F-9 as I was originally told by customer service. I'm glad someone that knew what they were doing intervened and shipped the correct part.

I'll still probably order the springs for the Gray Guns rod just to see if the added weight makes any difference and to have as a backup.

I did a little guided tinkering... an 18-18.5#, trimmed to properly fit the 320F spring tunnel, works well with the GGI fat rod and the 320F in .45. I am going to take a similar approach to my 320F in .357. However comma short pause... I’m thinking .357 will need a 20# spring. Thoughts?

I'm finally getting back to this. I bought Wolff 18.5 and 20 pound springs. I had to take about 5 coils off of each to make them fit. The 20 pound feels stronger than stock. The 18.5 feels about that same. Hopefully I can get to the range this weekend to test.

quote:

Originally posted by RichN:
I'm finally getting back to this. I bought Wolff 18.5 and 20 pound springs. I had to take about 5 coils off of each to make them fit. The 20 pound feels stronger than stock. The 18.5 feels about that same. Hopefully I can get to the range this weekend to test.

if you cut coils then you changed the spring weight.

I would never cut coils on a mainspring. Per majette, you have no baseline or even a guess as to what poundage you're running. No man's land.

Second, the GGI guide rod and 1911 spring(s) ARE more difficult to install than the captive. I have the same size P320 and Wolff springs for my .40. Be sure you have eye protection so that you don't end up with a GR in your eye.

Depending on the springs, the number of coils is only one component that determines he spring spec. Diameter, distance between coils and material can also come into play.

I bought GGI's GR/spring (9mm) and used a Wolff 1911 GM spring kit. With my own testing (17, 18.5, 20), it was difficult to detect major differences when using my standare handloads. While it seemed slightly happier with the 18.5 (subjectively and the ejection pattern) the differences were not great. Regardless of which Wolff spring I used, the recoil seemed to be slightly less with the factory OEM captive RS assembly. Folks that bought the GGI 9mm kit and used it in a nine stated that it did reduce muzzle dip, which is what it was intended to do.

The reason Bruce researched and developed his version for the P320FS 9mm was that the factory 9mm is "oversprung" for optimum results. The .40/.357 is not. Couple of years ago, Bruce posted in responce to my Q that he had done NO testing with the .40 since there was no issue to correct.

One way to determine if your pistol is happy with a given weight is ejection pattern. See Item 3:
https://www.gunsprings.com/index.php?page=FAQ

The problem is that SIG is not producing the 357/40/45 recoil spring assemblies with any kind of regularity, and they are next to impossible to find. I don't think Top Gun Supply even lists them, and the last time I ordered one from the SIG store they sent me a 9mm spring in a package labeled for 357/40/45, but now they are showing out of stock, even if I trusted them to get it right.

I know cutting the spring changes the weight, but it won't work at all if left at full length since it stacks solid before the slide has moved far enough. Also, since I'm using a non-factory spring, and SIG doesn't publish values, knowing the exact value isn't really important anyway. The only way to figure it out is going to be by experimentation.

As I said, I could tell that the 20 pound spring was noticeably harder to both unlock and to retract the slide to slide lock position. The 18.5 pound spring feels about the same as my last remaining factory spring, so I'm going to test it with some live fire before I wear out my last factory spring and have no baseline to compare to.

Again, I'm not looking for a competitive edge, I just want to shoot a gun I enjoy and SIG is apparently only supporting 9mm P320s now.

Hmmm. SigStore shows a kit with the .357/.40 RS assembly, but out of stock. TGS shows RS, but it's just the spring, not an assembly. I'm confused. Didn't think the assembly could be disassembled.

https://www.sigsauer.com/store...357-sig-45-auto.html

https://www.topgunsupply.com/s...-size-40-357-45.html

Regardless, from my own experience with my FS .40, the 18.5 would be my choice. I believe the .357 uses the same factory weight as .40 in other pistols. At least it will tide you over through the drought. Bummer. PITA trying to buy something as exotic as a Sig RSA.

Wish it was 1996 again when I bought my Sig P229. Life was simpler then.

I've been running the 18.5 pound spring for about a month now. I have about 500 rounds on it, a mix of full power and some slightly downloaded (1,250 fps) practice ammo. I've not had a single malfunction. Ejection has the same consistency as the factory spring, but the pile is about a foot closer, so I think that means the slide velocity is a bit slower, which should mean I have plenty of spring.

Glad it worked our for you.

Don't know if the shorter ejection distance has any significance. It's a single spring compared to a dual-spring RSA. The characteristics through the recoil cycle are different.

All that matters is that it works.

quote:

Originally posted by Nipper:
Glad it worked our for you.

Don't know if the shorter ejection distance has any significance. It's a single spring compared to a dual-spring RSA. The characteristics through the recoil cycle are different.

All that matters is that it works.

Actually, the full size has a single, flat spring from the factory.

Actually, you are actually right. My fingers got my dual-spring P320 9mm Compact mixed up with my FS .40.

Wonder why Sig did that. My Gen4 G19 and G34 both have dual-spring RSA's.

Don't know about you, but I long for the good ole simple days when I bought my P229 .40 in 1996. Sigh...

the OEM flat spring unscrews over the double-D end. on the full-size 320 OEM guide rod assy. the guide rod doesn't come apart. the slot on the end is to help you unscrew the spring off the guide rod.