Stovepipes with factory ammo SIG MPX PCC

[Fasthenk65]

After FTF with my loaded ammo now 3 stovepipes from the 100 shots with 115gn GECO factory ammo... Can anybody give me an idea what causes this? Slowly getting tired of the new Sig...

Edited September 29, 2019 by Fasthenk65

[ck1]

On 9/29/2019 at 11:55 AM, Fasthenk65 said:

After FTF with my loaded ammo now 3 stovepipes from the 100 shots with 115gn GECO factory ammo... Can anybody give me an idea what causes this? Slowly getting tired of the new Sig...

 

I would try running the bolt really wet (if you aren’t already), and letting your mags sit loaded for a few days to break in the springs, and then try some more factory ammo...?

 

I haven’t cleaned mine at all through 2000+ rounds and 2 matches now, and it has been flawless, but I’ve only shot factory stuff (cheap 115gr Tula and/or Syntech 130gr PCC-specific stuff), both well above 140pf and it still kicks like a toy nerf gun compared to a blowback gun. BUT I’ve oiled the bolt very wet (I mean lube all over the bolt) before every shooting session or match... so might be worth a try?

 

[Fasthenk65]

1 minute ago, ck1 said:

 

I would try running the bolt really wet (if you aren’t already), and letting your mags sit loaded for a few days to break in the springs, and then try some more factory ammo...?

 

I haven’t cleaned mine at all through 2000+ rounds and 2 matches now, and it has been flawless, but I’ve only shot factory stuff (cheap 115gr Tula and/or Syntech 130gr PCC-specific stuff), both well above 140pf and it still kicks like a toy nerf gun compared to a blowback gun. BUT I’ve oiled the bolt very wet (I mean lube all over the bolt) before every shooting session or match... so might be worth a try?

 

I will! Tomorrow I load all mags full and leave them for a few days... Bolt was wet since gun was cleaned just before... Mags can be the problem though the first 300 rounds were flawless..

[ck1]

1 minute ago, Fasthenk65 said:

I will! Tomorrow I load all mags full and leave them for a few days... Bolt was wet since gun was cleaned just before... Mags can be the problem though the first 300 rounds were flawless..

 

Cool, hope it goes well! Btw, when I said I run it “wet” I mean like almost dripping lol!

 

Thus far I’ve been lucky with my MPX as so far it’s been more reliable than other blowback guns I’ve had, and it’s just a joy to shoot because it’s so soft and flat shooting even at a higher pf, hope yours works too!

[vgdvc]

On 9/29/2019 at 12:55 PM, Fasthenk65 said:

After FTF with my loaded ammo now 3 stovepipes from the 100 shots with 115gn GECO factory ammo... Can anybody give me an idea what causes this? Slowly getting tired of the new Sig...

Can you describe your feed failures? What is your bullet profile? What were your loads? 115 can be kind of light in some factory loads. What I have noticed when reloading between 135 and 145 grain bullets didn't matter so much but I need it at least 3.1 grains powder to produce enough gas with these weights. This is with a medium fast powder such as Universal Clays or Sport Pistol. Anything less than that would not cycle the bolt enough. As soon as I hit 3.1 grains ejection was about 6+ feet away at a minimum due to the faster bolt cycle rate from a gas-operated firearm. This is also with the original Timney gold cased fire control unit which has a lighter hammer spring and yields on average 3.5 lbs pull. The black cased firiing control unit from Timney that came with the newer Factory MPX competition model has a heavier hammer spring, yielded 4.5 lbs and needed more powder to cycle the bolt fast enough for proper ejection.

[Fasthenk65]

no problems tonight with factory 115's after leaving the mags full one night and excessive oil on the bolt... hope this solves all...

[fbzero]

I was having similar problems with reloads when I first got mine, though I've never had a failure with factory ammo.  Sig rep happened to be at a steel match I was shooting and said to try running it "dripping wet".  I'm usually pretty conservative and don't run things dripping wet, but I went to a safe area and applied lube liberally, then got through the rest of the match without issues.  I have since been trying slide glide light, which I like because it stays in place pretty well, and have not had a failure with that either so far.

[Tattoo]

Factory 147’s run great in mine from day one.  

 

T