Folks, I have a rusty recoil spring.
Anyone know how to replace it?

Brownells has it:
https://www.brownells.com/hand...ring-prod108020.aspx

Can the recoild guide rod be disassembled?
https://www.brownells.com/hand...uide-prod108028.aspx

The first Brownells link is to the outer spring for the Compact and Subcompact models, not the M17 and full size.

In any event, the 9mm full size P320 recoil spring is color coded with orange paint that can look like rust. I suppose it’s possible you have a rusty spring, but it’s unlikely unless you’ve been dunking the assembly in seawater and not rinsing it afterwards.

If you want to change systems, though, I recommend the Grayguns separate rod and 1911 type recoil spring that will avoid the supply complications of the factory recoil spring assembly.
And there’s no paint on the springs that can be mistaken for rust, mold, or grape jelly.

Thanks for this recommendation.

The grayguns fat guide rod allows you to spring the pistol for your load: if you choose to shoot light loads, you can run a light recoil spring. Some say that the P320 full size is oversprung, and that it tends to lead to front sight dip when the slide returns, after a shot. A lighter spring may be preferred. Grayguns ships their rods with a 15 round spring.

I'm running my full size P320's with 12 lb springs presently, and I know some who go down to 9-10 lbs. 12-14 seemed to work best for me, using relatively light 147 grain rounds.

I think the pistol cycles more smoothly with the fat guide rod, and it does mean that for future spring changes or adjustments, you can replace the spring for less cost than a complete assembly. The fat guide rod assembly uses 1911 springs.

Thanks for the suggestions folks.
I'll have to keep it stock as this is an M17 surplus. It's now soaking in kroil.

quote:

Originally posted by ybrik:
I'll have to keep it stock as this is an M17 surplus.

Ah. That might explain the rust. I hope you weren’t offended by my suggestion that it could be paint rather than rust, but it’s hard to know about some things based on short Internet posts.

Good luck with your project.

quote:

Originally posted by sigfreund:

quote:

Originally posted by ybrik:
I'll have to keep it stock as this is an M17 surplus.

Ah. That might explain the rust. I hope you weren’t offended by my suggestion that it could be paint rather than rust, but it’s hard to know about some things based on short Internet posts.

Good luck with your project.

Not really sigfreund.
This is my first surplus item. Had few trips at the range last year, cleaning every trips and put it on safe. After 3-4 months in the safe, I was surprised small rust spots developed at the back of sear housing and trigger. Was really disappointed as all my other pistols didn't have it knowing that they are all in the same conditions inside the safe.
Upon closer inspection at the other parts, recoil spring and striker assembly spring had them too but not too apparent as on the sear housing.

I detail stripped the FCU last night and was surprised to see a safety lever spring even if this is already using the new "captive" safety lever.

I've got to check my FCU now, thanks guys.

You may be able to see this safety lever spring as its 2 ends are visible from the FCU.
Something that caught my attention as sig guy's M17 disassembly in YT didn't have it.

I was able to replace the factory spring on my Sig 320 full-size recoil spring assembly. I had to use a small flat-blade screwdriver to pry the end of the spring over the end-flat of the double-D end. Once I got that started, I inserted a screwdriver into the slot on the round end, and essentially unscrewed the spring off the recoil spring guide rod assy. The hard part is prying the end of the flat spring over the double-D and trying to rotate the spring at the same time to get it ledged on top of the double-D flat. once you get it started, the rest is easy.

when you reassemble the spring onto the factory guide rod, you start with the end of the spring that's not flattened. it just screws on. when you reach the end, the spring end at the flat end snaps over the double-D. The flattened end keeps the spring from unscrewing itself.

I needed a 9mm full-size spring guide rod assy to complete my 320 9mm full-size FCU parts gun, but out of stock everywhere. I was able to get a .40/357/45 assy (green paint), and separately was able to get a 9mm full-size spring (orange paint). Needed to remove the green spring so I could install the orange one.

This message has been edited. Last edited by: rpoL98,