STI DVC Steel recoil spring

[jrdoran]

I have a new DVC steel gun that has had some problems with stovepipe and also slide locking back on empty mag.  It locks back if manually pulled back w/mag in gun.   I've been shooting 115gr store bought ammo.  The gun does cycle somewhat better with 124 or 147 ( at least lock back ) but still from stovepipe and f2f issues. 

 

STI sent me a new recoil spring as it should have a 7lb and they thought maybe it got the wrong one.  I don't have a way to measure but see the pic.  The longer spring is the newly arrived 7lb spring from STI.  The coils do seem farther space / less dense.    The original spring is exactly 6".  I forgot to measure the new one, I'd estimate 6.75-7".

 

Is it reasonable to think the 7lb spring is the longer spring ?  Also as the gun is a 4.1" barrel, I'm wondering if they just sent me a generic 5" government spring and the stock one is a special length.

Edited December 12, 2017 by jrdoran
typo

[CamboSoup22]

I don’t think you will be able to go by length alone. I run a Shorty open pistol as well and I use the govt springs. The springs will develop a little memory after use. And compress a bit. Give it a shot and see if it performs better. The 115 just may not provide enough to work the slide properlywith the comp. May take some breaking in? I’m sure you have, but have you considered reloading? Comped pistols are much more entertaining when reloading. 

[cecil]

Ditch the upright scope mount... install a horizontal mount... stove pipe problems will cease... 

[jrdoran]

Yes, the scope mount has been a topic of considerable thought, either horizontal or offset.     Can I 'fine tune' the spring by cutting off coils 1 at a time and trying it ?   

115gr ammo seems to shoot flatter than the 124 given greater charge for the comp.   

[cecil]

if you use different head stamp brass.. there is just enough difference to cause problems.... I changed the scope mount for the same reason you stated... (stovepipes) since I change to the vertical mount on my STI DVC 9mm I have not had any more problems...

[Honkeymcgee]

I wouldn't cut the spring until trying it. 

 

A 7lb spring should be plenty light to run factory ammo. 

 

As for the scope mount, I have had 9mm open guns that ran just fine with the normal Cmore mount. Changing the Cmore mount is just an easy fix. 

[jrdoran]

Update:  With the new spring, the gun ran flawless tonight with 100 rounds of WWB 115gr and also some winchester 146gr training ammo.  I'm pleased. 

[Steelix]

Glad the spring changed got you going, without putting anymore more money into the gun. Now go have fun with the gun. 

[jrdoran]

Update:  Even with the spring change and now close to 1000 rounds ( I run it very wet ) I still have occasional stove pipes every 200-300 rounds.  

[CamboSoup22]

Interesting. I haven’t had to do it but I hear one of the options is to look up tuning the ejector. You can change it a little to get it to eject more reliably. One of the things people do when running a cmore. As others have stated you can also change to the 90 degree mount for the cmore. The ejected brass could possibly be hitting the cmore and causing the stovepipe. Those are the cheaper options. You could also change to a micro dot mount but that means you have to buy a microdot. 

[Steelix]

If you use mixed brass see if it's the same head stamp brass that's stove piping. 

[jrdoran]

7 hours ago, Steelix said:

If you use mixed brass see if it's the same head stamp brass that's stove piping. 

 

Can you educate me on how I determine this.  I'm using production ammo  ( Speer Lawman, WWB, Federal ) 115gr 9mm;  

 

Is production ammo 'mixed brass' ?   If so, could you explain what I should look for. 

[CamboSoup22]

I believe what steelix is referring to is the marking at the bottom of the brass. Most of us reload and use once fired brass so it comes from everywhere. Since you’re using factory ammo I don’t think that’s the case unless you are loading a couple from each brand/box and then shooting. Then you would need to track which one is failing. 

 

Your latest post only mentioned 115’s. Is that all you are shooting now? I ask since earlier you said the heavier bullets cycled better. Does the 115 that you are shooting allow the slide to fully lock back consistently? If it doesn’t maybe the issue is the slide short stroking and not allowing the brass to properly eject. 7lb spring should be enough but maybe there is something a little tighter that needs to be broken in on your pistol. You wouldn’t happen to be in the Dallas area would you? I’ve got some springs that I keep around for tuning purpose that I would loan you if you are. That way you wouldn’t have to wait for shipping or order more. 

[Steelix]

Yes sorry I thought you reloaded. But you said you run your gun wet. If the gun is still tight and it has to much oil on you could be slowing down the slide. Do you get the stove pipes after the gun gets hot form shoot a long string of rounds. You could try backing off the oil a little bit. 

[cecil]

I experienced the same problem with my DVC ... did lots of adjustments to the ejector .. still had stovepipes... changed the factory scope mount.. installed a vertical mount... stovepipes ceased .. 

 

 

[jrdoran]

@CamboSoup22 Thank you for the generous offer of help on the springs.  I did order a pack ahead of time with springs down to 5#.     Yes the slide lock is now working well with 115gr.   I'll take some pics, but I do notice marks on the bottom of the factory scope mount.    +1 Cecil 

 

I do test with 124gr, but honestly the stove pipe is so random that I can't say for sure if 115 or 124 has a higher frequency.   I do think 115 shoots flatter.

[jrdoran]

Assuming I change to a vertical mount for the c-more, which one does everyone recommend ? 

[CamboSoup22]

Not sure if you changed your thumb rest but here is some stuff to think about with pictures. Page 2 has more images. 

 

[jrdoran]

I'm left handed, so the mount is separate from thumb rest.  Beautiful guns in those pics. 

 

Ideas on 90 degree  mounts ?  Cheely with or without setback ?   BCG - Slipstream H (Horizontal) Scopemount ?

[CamboSoup22]

I haven’t used any of them but if you went with cheely I would have it set back. My thoughts is since you have a shorter pistol keep it as far away from the compensator for any blast. Also having the sight a closer to you makes the glass seem even bigger. When I first found myself doing the dot dance I would bring the pistol in a little closer to me to find the dot quickly then drive back to a normal shooting position. 

[jrdoran]

Found this very useful thread here on the forums;    

 

 

 

[Exlonghorn]

jrdoran, now that some time has passed, how are things progressing?  Did you switch out your optic mount?  

 

After doing some math, I find that my STI DVC-S doesn't like to cycle anything under a 140 power factor.  That knocks out almost all 115gr options, but there are several inexpensive factory 124gr loads I can buy in buik.  I"m still in the break-in period, but like you, I am having stovepipe/FTF issues with anything having a power factor under 140.

[jrdoran]

On 4/7/2019 at 1:09 AM, Exlonghorn said:

jrdoran, now that some time has passed, how are things progressing?  Did you switch out your optic mount?  

 

Yes, I went with the Cheeley Cmore Horizontal Setback Scope Mount and it was a game changer at eliminating stovepipe issues.   I also dropped the  recoil spring to 7lbs via a standard wolf spring.  I literally run almost any ammo in the gun regularly.   My normal load is atlanta arms 100gr at about 105 power factor.    

[geraldskip]

17 hours ago, jrdoran said:

 

Yes, I went with the Cheeley Cmore Horizontal Setback Scope Mount and it was a game changer at eliminating stovepipe issues.   I also dropped the  recoil spring to 7lbs via a standard wolf spring.  I literally run almost any ammo in the gun regularly.   My normal load is atlanta arms 100gr at about 105 power factor.    

105 PF? Dang that is crazy. I bet that thing is a blast to shoot.