Recoil Spring Life Expectancy

[brisix]

What is the round count we can get out of the Scorpion recoil spring?  What type of malfunctions would we expect to see once its starts to go bad?

[armoredman]

Hmm, no idea, but I think the industry standard has been for some time about 25,000 rounds before needing repair/replacement wear parts, which the recoil spring would be. Good question.

[wyoung]

The CZ rep I spoke to said 10k rounds to be safe and 20k max.

[SouthernScorp]

well !@## I guess in another 3k rounds I need a new spring 

[armoredman]

Yep, I'd better get one too.

[wyoung]

Don't take it as the gospel. Lol
I'm just passing along the message.

[brisix]

With the amount I shoot, it would be a twice a year thing.

Any videos out there showing a full break down of the bolt?

[Ghostv2]

These things were made pretty robust for the high rate of fire they see in military and law enforcement use. I mean look at the giant bolt for instance. For the amount of stress we put on them as civilians in semi only mode has to extend service life to some extent. So did they specify under what conditions those estimates are for?

[wyoung]

These things were made pretty robust for the high rate of fire they see in military and law enforcement use. I mean look at the giant bolt for instance. For the amount of stress we put on them as civilians in semi only mode has to extend service life to some extent. So did they specify under what conditions those estimates are for?

No he didn't and I got the impression it wasn't something he was extremely knowledgeable about. I think that's why he gave me the 10-20k range.

[brisix]

I have an answer... at least for my rifle.   I am around 8k rounds.   I started to have failure to feed with my 30 round mags in practice but I contubuted that to the rifle being dirty.   It had at least been 5k round since I cleaned it.  I figured the FTF were due to the rifle being dirty.  I cleaned it before my first major USPSA match shooting PCC, Oklahoma sectional.  I did a reliablity check with my taylor freence +10 mags and 30 round mags right before the match and everything worked.   The first day of shooting, 6 stages, no issues.  The second day of shooting I had 3 FTF on 3 of 6 stages with two different TF mags.  My first thought was the extended mags springs had worn out but the jam would happen in the first 7 of 40 rounds.  From what I can remember, the round would enter the chamber but the bolt would not be able to engage the round fully.

After chrono I started to think it was the recoil spring.   I chrono'd an average of 1100 across three rounds.  My average back in February was 1189 across 10 rounds.   The rifle had about 2-3k rounds on it.

I replaced the recoil spring.  I chrono'd 1164 across 10 rounds.  The number I would expect. 

The rifle runs 100% again.

I will start to replace the recoil spring every 5k rounds, or once a quarter.   This is the same round count I replace the recoil spring in my SP-01.   

Load
Berry's 124HBRN, 4.0Gr Titegroup, OAL 1.160. Mixed brass

https://youtu.be/-UGEV4t4GVc

   

[wyoung]

I have an answer... at least for my rifle.   I am around 8k rounds.   I started to have failure to feed with my 30 round mags in practice but I contubuted that to the rifle being dirty.   It had at least been 5k round since I cleaned it.  I figured the FTF were due to the rifle being dirty.  I cleaned it before my first major USPSA match shooting PCC, Oklahoma sectional.  I did a reliablity check with my taylor freence +10 mags and 30 round mags right before the match and everything worked.   The first day of shooting, 6 stages, no issues.  The second day of shooting I had 3 FTF on 3 of 6 stages with two different TF mags.  My first thought was the extended mags springs had worn out but the jam would happen in the first 7 of 40 rounds.  From what I can remember, the round would enter the chamber but the bolt would not be able to engage the round fully.

After chrono I started to think it was the recoil spring.   I chrono'd an average of 1100 across three rounds.  My average back in February was 1189 across 10 rounds.   The rifle had about 2-3k rounds on it.

I replaced the recoil spring.  I chrono'd 1164 across 10 rounds.  The number I would expect. 

The rifle runs 100% again.

I will start to replace the recoil spring every 5k rounds, or once a quarter.   This is the same round count I replace the recoil spring in my SP-01.   

Load
Berry's 124HBRN, 4.0Gr Titegroup, OAL 1.160. Mixed brass

https://youtu.be/-UGEV4t4GVc

 

Did you test using the TF extensions after you replaced the recoil spring or factory mags? Do you have an aftermarket mag release?

I have a friend that had an aftermarket mag release and TF extensions who had FTF issues during a USPCA, USPSA or some such competition. He reinstalled the factory mag release and ran flawlessly after that.

[akuser47]

I am approaching 10000 rounds on mine and I haven't had issue yet but I guess I will need to replace mine or at least keep a spare ready.
Thanks for this thread I will be ready.

[brisix]

I tested with both TF extension and factory mags.  I use a Yetiwuks mag release.