New SIG P938 malfunctions: ideas?


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1KPerDay
August 10, 2012, 12:59 PM
A friend of mine just got a 938; we shot it for the first time last night. Impressively accurate, fun to shoot. First couple of mags no malfunctions, then had a FTE/Type 3 malfunction on the 4th magazine through, and again on the 6th magazine through. Then about magazine 8, last round FTE and remained partially in the chamber. Then about mag 11, last round FTF and was sitting on the magazine, slide locked back.

Ideas? First I was thinking extractor issue.....

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kokapelli
August 10, 2012, 04:41 PM
Brand new guns sometimes need breaking in and a good cleaning.

1KPerDay
August 10, 2012, 05:16 PM
It's clean and lubed. I guess we'll run a couple hundred rounds through it and see how it goes. The FTEs are what concerned me most.

kokapelli
August 10, 2012, 05:21 PM
It's clean and lubed. I guess we'll run a couple hundred rounds through it and see how it goes. The FTEs are what concerned me most.
Did you try more than one brand of ammo?

powder
August 10, 2012, 05:27 PM
Take the mags apart and clean them too.

bluecollar
August 10, 2012, 05:27 PM
Recently got a new 938 that I haven't shot yet. What I have heard and read is that they need a fairly extensive break in (200 rounds seems to be the number). I knew this going in so I'm prepared for it. Have been doing a lot of dry firing and the trigger seems to be crisper without the creep that it had when I got it.

1KPerDay
August 10, 2012, 05:42 PM
Did you try more than one brand of ammo?
Yeah, 3 different kinds. All brass cased

Skribs
August 10, 2012, 05:53 PM
That's better than what happened to my Dad. Firing pin retainer (I think the part is called) fell out and locked the slide back. He sent it to Sig, they said "it MUBAR" and sent him a new one.

I'm paraphrasing the conversation, of course.

WYO
August 11, 2012, 07:30 AM
I like my P938. It was a very tight gun from the factory, and here is my suggested break in. Load the magazine(s) as soon as you get it (them) and let it (them) sit until you use it (them). Clean it and liberally lube it, including the top of the barrel hood. Rack the slide a couple of hundred times. Clean the rails and hood again and liberally lube it the same way. Chamber a round if safety conditions permit so the extractor gets some tension on it until you finally shoot it. Shoot 124 grain full power ammo. Don't shoot it for extended shooting sessions unless you check it and it still is wet. I have had 5 malfunctions in mine, 4 from Wally World Winchester white box 115s. 3 were in the first magazine. I had one malfuntion with a Speer 124 gr. Gold Dot, and that was at about round 160. Since then, it has gone 250 124 grain Gold Dots and Blazer aluminum with no trouble.

1KPerDay
August 20, 2012, 07:10 PM
did you have any failure to extract?

Esoxchaser
August 20, 2012, 07:16 PM
I recently picked up a 938. 500 rounds through it now. Not one issue whatsoever.
Blazer FMJ, Cheap white box Federal FMJ, Magtech FMJ, Hornady Critical Defense.
All in 115's. Trust it enough I carried it today.

1KPerDay
August 22, 2012, 01:14 PM
Another 50 rounds through last night, only one malfunction this trip.
http://i12.photobucket.com/albums/a206/1KPerDay/Guns/SIG%20P938/28801257.jpg

Trigger still not the best. Pistol is pretty accurate for a little thing. Fun to shoot.

WYO
August 22, 2012, 01:37 PM
did you have any failure to extract?

Yes, 3 in the first magazine with 115 WWB, one at around round 60 with the same ammo, and 1 at round 160 with a 124 Gold Dot. I started using the TW25B (that was in the sample pack in the box with the gun) and Break Free, and shooting 124 Blazers and Gold Dots, and no more failures to extract.

hardluk1
August 23, 2012, 06:46 PM
The breakfree is what I use too. Did you take the mags apart and clean?? Since everything is ejection related besure there no burs or crud on or around the ejector . This trick has worked for me and others of decades. If you have a battery drill and some metal polish or jbs take a nylon bore brush and put it in the drill and wrap enough cotton patch around it to make a tight chamber fit and with the polish give the chamber and slow in and out for 10 seconds max. It will clean off any sharp edges during chambering and not hurt the chamber. Clean well and see if that stops the FTE. Use some 124gr for a while too. Try HP after you run a couple hundred fmj first. I have allways had good luck with magtec ammo for break in.

SN13
August 23, 2012, 09:01 PM
There are ALOT ALOT of guns (yes i said it twice).... With a Fail To Extract issue where the round fails to get out of the chamber and the next round gets jammed up behind it.

I called SIG Customer Support on mine. Here is what they told me:

"90% of the guns we get in with FTE issues, we cannot duplicate. We believe it is recoil sensitivity of the shooter."

YMMV.

Sergei Mosin
August 23, 2012, 10:48 PM
Didn't SIG initially blame the P238 problems on the shooters as well? Turned out to be a recoil spring problem, mostly.

It seems pretty obvious that there is a flaw with the extractor design and setup on the P938, but SIG is doing the "blame the customer" thing again. I sort of suspected this was going to happen with the change from an internal extractor on the P238 to an external extractor on the P938; they are also having problems with the longer extractors on other P-series pistols.

SN13
August 23, 2012, 11:43 PM
Shocking. My extractor was so long that in its MOST open position possible, that the spec Base Diameter of a 9mm cartridge (.392") was .004" wider than my maximum open position.... FOUR THOUSANDTHS.

Certaindeaf
August 24, 2012, 12:00 AM
There are ALOT ALOT of guns (yes i said it twice).... With a Fail To Extract issue where the round fails to get out of the chamber and the next round gets jammed up behind it.

I called SIG Customer Support on mine. Here is what they told me:

"90% of the guns we get in with FTE issues, we cannot duplicate. We believe it is recoil sensitivity of the shooter."

YMMV.
Yea, post #12 looks like it was because "the shooter was recoil sensitive". not

SN13
August 24, 2012, 07:46 AM
Obviously a Failure for the claw to drag the casing out of the chamber is a result of limp-wristing it! We all know that! :rolleyes: :banghead:

1KPerDay
August 24, 2012, 01:09 PM
Wild. However, why does a "too-long" extractor fail to rip the case out of the chamber? Is the rim camming the extractor outward too far so that the inside rear edge of the extractor is angled forward slightly or something?

Just trying to wrap my mind around this. If anything, my caveman brain says that if the extractor is too long (and the round chambers with the extractor in the rim properly) it should work TOO well, and maybe hold onto the case after the front clears the chamber or something.

Thanks for your help.

SN13
August 24, 2012, 03:49 PM
Wild. However, why does a "too-long" extractor fail to rip the case out of the chamber? Is the rim camming the extractor outward too far so that the inside rear edge of the extractor is angled forward slightly or something?

Just trying to wrap my mind around this. If anything, my caveman brain says that if the extractor is too long (and the round chambers with the extractor in the rim properly) it should work TOO well, and maybe hold onto the case after the front clears the chamber or something.

Thanks for your help.

Good Question.

All the casings I pulled out that Failed to Extract, looked as though the extractor scraped the rim from the base forward to .002" from actually jumping the rim. It was as if the extractor never made it completely over the rim and was just jabbing into the side. THAT would cause a FTE. That was my initial assumption.

Here is a Professional Artist's Rendering.

http://i.imgur.com/J1cMj.jpg (http://imgur.com/J1cMj)

Orion8472
August 24, 2012, 04:13 PM
That's how my mind imagined it. Nice drawing. :)

I wonder what percentage of the P938 pistols out there have this issue? May need to be addressed before I plunk down nearly $700 for one.

SN13
August 24, 2012, 04:25 PM
Now, keep in mind that a 9mm rim base within spec should be:

Rim diameter 9.96 mm (0.392 in)

(SEE 9mm Wiki (http://en.wikipedia.org/wiki/9mm) for more measurements)

0.392 Inch Diameter. My Extractor measured .388" from the claw to the other side of the breach face (AT maximum open).

I'm sure that most 9mm casings are .392" or less within some specified range. The FEW casings that were at the high-end of within spec, were having the issue (assumption).

You can see all my measurements here: http://www.thehighroad.org/showpost.php?p=8359968&postcount=29

CPshooter
August 24, 2012, 04:48 PM
I called SIG Customer Support on mine. Here is what they told me:

"90% of the guns we get in with FTE issues, we cannot duplicate. We believe it is recoil sensitivity of the shooter."
That just makes me angry when I read something like that. I'm very happy with my non-railed CPO P229, but I can't see myself ever buying another Sig. The way that company has been run over the last 6-8 years makes me sick.

1KPerDay
August 24, 2012, 04:50 PM
How would the length of the claw prevent full engagement? Wouldn't it be the horizontal length of the extractor shaft (parallel to the bore) that would determine that? thanks for your patience

1KPerDay
August 24, 2012, 04:52 PM
Wait, I think I get it. Friction of the too-tight claw on the outside edge of the rim? But wouldn't that hold the slide out of battery slightly?

SN13
August 24, 2012, 04:57 PM
How would the length of the claw prevent full engagement? Wouldn't it be the horizontal length of the extractor shaft (parallel to the bore) that would determine that? thanks for your patience
I originally thought this as well.

I removed the slide and took out the barrel. When I push the round into the claw, there is a little wiggle-room. Also the measurements of the space between the claw and the breach-face indicate that it is larger than a within-spec rim thickness.

So I looked at other possibilities.

SN13
August 24, 2012, 04:59 PM
Wait, I think I get it. Friction of the too-tight claw on the outside edge of the rim? But wouldn't that hold the slide out of battery slightly?
Yes, And I had 2 instances of failure to return to battery on my first outing as well.

The slide was 99% closed and I physically could NOT bump the slide closed with my hand. I had to remove the mag and sling-shot the slide onto the chambered round and reinsert the mag.

1KPerDay
August 24, 2012, 06:17 PM
Have we determined whether the extractor is surface-hardened? Did you do any hardening after your mods?

SN13
August 24, 2012, 07:38 PM
I only polished mine with a jewelers file after the initial reduction.

I'm not suggesting anyone do this with their gun. I'm only saying what I did and what i learned.

I removed some length and re-shaped the "angle" to make it easier to get out of the way.

Be careful of the fact that the lower "hanging" tab portion of the extractor claw is what actually pulls the round out of the chamber once the barrel tilts. It is NOT advised to remove as much from this area as from the top area which would be where the claw grabs when the chamber is in battery.

Remember there are no "Spare" parts. Only do this if you know that you may have to wait 6 months for a new extractor claw.

1KPerDay
August 26, 2012, 04:21 PM
Understood.

50 more rounds yesterday, 124 grain remington, 3 malfunctions. 2 left the round in the mag below the non-extracted case, and one left the nose of the incoming round against the rear of the non-extracted case. Guess I'm limp-wristing again. :rolleyes:

pic of the cases if it tells you anything. There are scratches both on the edge of the rim and on the deepest inside diameter of the groove.

http://i12.photobucket.com/albums/a206/1KPerDay/Guns/SIG%20P938/ad3b379b.jpg

http://i12.photobucket.com/albums/a206/1KPerDay/Guns/SIG%20P938/5a46cdc4.jpg
http://i12.photobucket.com/albums/a206/1KPerDay/Guns/SIG%20P938/2c589fc0.jpg

dcarch
August 26, 2012, 09:36 PM
This is why I always like to give a new gun a good year or so on the market before I pick it up.

1KPerDay
August 28, 2012, 06:29 PM
Update: owner took it back to the LGS/range today, they put 100 rounds of Remington bulk through it with no issues. 50 were shot by a 16-year-old girl, weak hand, strong hand only, both hands, etc. Both magazines. No malfunctions. LGS suggested we put another couple hundred rounds through it, and if we experience any more issues they'll send it back.

we'll see.

SN13
August 28, 2012, 08:25 PM
1kperday.

Good to hear.

Maybe it's just coincidence that my fine-tuning coincided with the break-in and it was coincidental that the gun worked well.... Maybe.

:)

YMMV

1KPerDay
August 29, 2012, 01:23 AM
:D...

1KPerDay
September 6, 2012, 12:57 PM
113 more rounds, no failures to extract, but one FTF on the last round in the magazine. 50 Federal, 50 Remington 124, 13 magtech 115 grain. I tried strong hand only, weak hand only, etc.

I guess it's "wearing in..."

Hopefully...

SN13
September 8, 2012, 09:10 PM
My round count is up to 550 now. And since my modifications, i've had NO failures to extract.

I did have TWO FTF with some 147gr Winchester White Box JHP. But both were quickly cleared with the Tap-Rack-Bang... way better than the FTE jam.

Flawless with the 115's and 124's and OTHER 147s I've used. The two FTF's nose-dived into the ramp.

1KPerDay
September 12, 2012, 07:36 PM
Another 50 rounds... one FTE. Dang it...

Federal 90 grain frangible. Doesn't give any issues in my other 9mms... but maybe an issue. The ones in the pics above are all Remington 124.

SN13
September 13, 2012, 10:59 AM
90gr Frangible? seems a bit light :)

1KPerDay
September 13, 2012, 11:16 AM
Oops... it's 98 grains. I remembered wrong. Like I said they run fine in all my other 9mms. Good for shooting steel indoors.

http://www.aimsurplus.com/product.aspx?item=AFED9F98&name=Federal+LE+9mm+Frangible+RHT+98grn+50rd+box&groupid=46

wtxj
September 13, 2012, 11:22 AM
Good price on the 98 grain. My little 938 had the FTE only with WWB. Used the American Eagle cheap stuff and had no problems. Have shot 115's up to 147's.
I do run it wet.

SN13
September 13, 2012, 01:01 PM
Good price on the 98 grain. My little 938 had the FTE only with WWB. Used the American Eagle cheap stuff and had no problems. Have shot 115's up to 147's.
I do run it wet.
I keep my guns as dry as possible.

Three thoughts on that:

#1, I don't usually find my pistols getting more-lubed as they sit in my pocket all day.
#2, I don't see as much lint caked inside the gun when it's dry as when it's wet.
#3, I don't like the thought that if i don't have Y-amount of X-product on the gun, it won't work. I like to know that even dry as the Sahara, it's going to run.

~SN13

wtxj
September 13, 2012, 01:17 PM
I used to worry about the link issue, but my pocket holster seems to have cured that. I don't know but I sure do like the grease that came with my P938. Run it on the rails, run it on all of my auto rails, at this time. Keeps the wear factor to a minimum on rails.

What I'm hoping is soon as I get another 200 or so rounds down range, I'm going to run another box of WWB. I had FTE time after time when the pistol was brand new in June only with the WWB. Hoping this P938 will shoot them without any problems at that time. ;)

The Lone Haranguer
September 13, 2012, 02:43 PM
Another 50 rounds through last night, only one malfunction this trip.
A double feed - caused by failure to extract - is an extractor problem. The case should still be pulled out of the chamber, regardless of how firmly you hold the gun.

SN13
September 13, 2012, 03:26 PM
A double feed - caused by failure to extract - is an extractor problem. The case should still be pulled out of the chamber, regardless of how firmly you hold the gun.
Precisely.

The extractor physically cannot open far enough to accept the rim of a within-spec rim on the large size.

My extractor had a 4 thousandths of an inch short-fall on it opening enough per rim diameter spec. The Rim Diameter should be .392" (9.96mm).... My claw could only open to .388"... Doesn't take a genius to know you can't fit a 9.96mm circle into a 9.85mm hole.....

Remllez
September 14, 2012, 07:05 PM
OP,

Could it be a tight chamber in your P938? When you have the barrel out of the gun and hold it chamber up, will your ammo of choice drop in with a plunk? Everything I've read here points to a tight chamber, the extractor running over the rim is indicative of a chamber problem.

Just a thought and it's easy enough to check yourself. I'm pretty sure it isn't limp wristing, that seems to be the new go to excuse for gun manufacturers.

1KPerDay
September 14, 2012, 10:23 PM
I'll check it... but I'm pretty sure it's an extractor issue as noted above.

TimboKhan
September 14, 2012, 11:40 PM
"professional artists rendering"


Lol, informative and funny!

SN13
September 17, 2012, 02:43 PM
OP,

Could it be a tight chamber in your P938? When you have the barrel out of the gun and hold it chamber up, will your ammo of choice drop in with a plunk? Everything I've read here points to a tight chamber, the extractor running over the rim is indicative of a chamber problem.

Just a thought and it's easy enough to check yourself. I'm pretty sure it isn't limp wristing, that seems to be the new go to excuse for gun manufacturers.
The extractor jumping the rim durring extraction would point to a tight chamber.... but this is not the case.
The extractor sometimes fails to get ONTO the rim in the first place.... it's an extractor issue.

gcburt
September 17, 2012, 06:28 PM
Anyone ever use FrogLube on their P938?

kokapelli
September 17, 2012, 08:08 PM
Anyone ever use FrogLube on their P938?
How would that relate to the subject of this thread?

gcburt
September 19, 2012, 11:03 AM
I asked about anyone using FrogLube on their P938, because there are entries about cleaning, firing wet and firing dry in this thread.

A friend suggested FrogLube and I'm wondering if that will help prevent potential FTE malfunctions when I go to fire my P938!

tomrkba
September 19, 2012, 12:12 PM
Call SIG and have them work on it. They will tweak it so it works.

kokapelli
September 19, 2012, 01:28 PM
I asked about anyone using FrogLube on their P938, because there are entries about cleaning, firing wet and firing dry in this thread.

A friend suggested FrogLube and I'm wondering if that will help prevent potential FTE malfunctions when I go to fire my P938!
I see, but I can't believe that a specific brand of lubricant could make the difference and if it did I sure wouldn't want that pistol.

1KPerDay
October 22, 2013, 02:06 PM
Update: Just got the pistol back from SIG for the second time. First time they inspected the pistol, "detailed the breech face", replaced the extractor SPRING, and test fired 50 rounds.

Got it back, still FTE. Sent back to SIG and they had it a couple months. Replaced extractor and included a spare extractor in the box.

Cleaned, lubed, and test fired yesterday, around 160 rounds. 40ish rounds Herter's select brass cased 115 FMJ (made by Fiocchi I believe, possibly S&B), 100 rounds PMC bronze 124 FMJ, and 6 rounds Hornady 115 Critical Defense, 15ish rounds Speer Gold Dot.

Results... ZERO FTE!! Yaaay!

However, one FTF with hornady, one failure to return to battery with PMC (extractor didn't slip over the rim), and multiple light primer strikes/failures to fire with Herter's. All herter's fired when re-struck a second time.

Primer strikes have always been very light on this pistol, and I had one failure to fire in previous shooting. Is a longer firing pin available? I don't suppose a lighter firing pin spring is a good idea... right?

Video for any interested.
http://www.youtube.com/watch?v=2oZ1cBlCxSo

decoy562
October 23, 2013, 01:12 PM
Sorry to hear of your issues. My wife loves her's after we broke it in, I believe we had a few FTE's at the beginning.

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