P07/40 Duty issues

[Indy_Tim]

Last Saturday, I bought a used P07 Duty in .40 S&W with the intention of using it for my winter carry pistol.  On Sunday, I took it to the range and ran a quick 50 rounds through it.  All functioned well.  I also own a P07 Duty in 9mm and that pistol has been almost fully Cajunized by a local smith here in Central Indiana.  That is a fantastic pistol but since I don't often carry a 9mm in the winter, I decided to swap parts and move the Cajun goodies over to my new P07.  That was not a good idea it seems.  I swapped the trigger bar, springs, firing pin, roller, disconnector, FPS lifter and hammer over to the new gun.  It felt great.

On Thursday, I took it to the range and was having a lot of issues with it in that it now has a tendency to let rounds nose dive instead of chambering correctly.  If I put a slight be of rearward pressure on the slide, the round pops up and chambers normally.  Figuring that I should have left the two pistols be, I swapped most of the parts back between them but left the CGW slide parts (FP, FP safety spring, roll pin) and gold hammer spring in the .40 P07.  I'm still getting the FTC though and am wondering if the .40 needs the heavier hammer spring to slow the slide a bit.  Also, I did notice that this pistol launches brass about 25 feet as compared to my P09/40 that seems to drop it only about 10 feed back.

My next plan will be to swap the slide components and go back to the heavier main spring to see if that makes a difference.  Part of me is wondering if the first 50 rounds may have been a fluke though too.

Any thoughts on what would cause the rounds to nose dive instead of chambering normally?  I'm running the same reloads that work fine in my P09/40 and G23.

Thanks in advance for any advice you can give,

Tim

[copemech]

If it is throwing brass 25 feet, you need a recoil spring!

[Indy_Tim]

Does anyone know what the stock recoil spring weight is?  I see on CGW's site, that they offer a gold 15# and a yellow 18# spring.  Both of my P07s have a blue spring.  I'm assuming that the 18# would be appropriate, but am wondering what came in it from the factory.

[Indy_Tim]

Parts are inbound.  When done, it will sport the full CGW Property package minus the hammer. It will also get a SS guide and fresh spring

Sent from my SM-G930V using Tapatalk

[Indy_Tim]

This is getting to be quite frustrating.  I did another range trip and am still having issues with the P07 Duty in .40.  The gun has been polished internally and is running a mild CGW tune.  By that, I mean it has the SRS cams, .220 roller (replaced a .213), extended firing pin with light spring, lighter FPS lifter spring, yellow hammer spring, lighter TRS and upgraded FP retaining pin.  It feels great in the hand and cycles beautifully manually.  I replaced the recoil spring with a yellow 18# spring and SS guide rod.  It should be a fantastic shooter.  And when it's working, it is.

The issues are that it's getting a consistent FTF with the nose of the round diving into the bottom of the feed ramp.  Right now, this is happening with the stock 12 round mags, but the gun seems to run fine with the mags from either my 9mm P09 or my .40 P09.  The stock 12 rounders have been disassembled, cleaned thoroughly and lightly lubed inside with a spray on dry film lube.  They feel great, like a good Wilson Combat 47D.  I thought that maybe the mag springs might be tired and swapped the mag springs in a P09 mag with the mag springs in one of the P07 mags.  The P07 mags failed to run reliably and the P09 ran fine, so I think I can rule out the mag springs and followers.  I'll check the dimensions of the feed lips to see if there are any odd dimensions there.  They look correct to me visually though.

When manually cycled, the gun feels great.  If I cycle with the recoil spring removed, I cannot get it to jam even if I push the round down.  Even with the new recoil spring and guide rod, it's still throwing brass about 20 to 25 feet, which seems awfully far for a .40.  All of my other .40s seem to toss it about 10 to 15 feet, no further.

Are there any known issues with the early .40 P07s?

[M1A4ME]

I've got a DUTY P07 in .40 S&W.  All stock internally.  I've not had any feed issues with it, with any of my magazines (P07 12 rounds or P09 15 rounds).

Not sure what factory ammo/brass ejects like as I've never shot any.  My pretty hot 135 grain hollow points toss the brass way off to the right/up.  Sometimes they bounce off the roof of the pistol range overhead cover on their way 15 feet or more away from me to pile up on the ground off the concrete floor.

I think the factory recoil springs are pretty "tight".  If I remember correctly the spring in my P07 has just as many coils as the recoil spring in my P09 and they are already compressed in the shorter P07 slide/frame.  Then again, I ordered a newer "captured" recoil spring/guide assembly for mine and opened up the hole in the front of the slide to accommodate the larger diameter guide rod that unit uses.  I got tired of fighting that loose spring/guide on reassembly they used in the DUTY model guns.

[Indy_Tim]

I've got a DUTY P07 in .40 S&W.  All stock internally.  I've not had any feed issues with it, with any of my magazines (P07 12 rounds or P09 15 rounds).

Not sure what factory ammo/brass ejects like as I've never shot any.  My pretty hot 135 grain hollow points toss the brass way off to the right/up.  Sometimes they bounce off the roof of the pistol range overhead cover on their way 15 feet or more away from me to pile up on the ground off the concrete floor.

I think the factory recoil springs are pretty "tight".  If I remember correctly the spring in my P07 has just as many coils as the recoil spring in my P09 and they are already compressed in the shorter P07 slide/frame.  Then again, I ordered a newer "captured" recoil spring/guide assembly for mine and opened up the hole in the front of the slide to accommodate the larger diameter guide rod that unit uses.  I got tired of fighting that loose spring/guide on reassembly they used in the DUTY model guns.

I was measuring magazine feed lips tonight and found that the feed lips on a 9mm mag are about .030" smaller than the feed lips on the P07/40 magazines.  What's interesting is that the P09/40 magazine feed lips are .010 smaller than the early P07/40 Duty magazines.  Did CZ change the Spec on the 2nd version of the P07/40 magazines I wonder?  Does anyone have a P07/40 magazine that they could check the size of the feed lip at both the front and rear?  I was seeing .388 at the front and .386 at the rear on the P07/40 mags with the P09/40 mags measuring .378 even.  I hate to throw more money at this gun, but I think I need to buy at least one new P07 mag to see if that makes a difference.  .010 could cause the difference that I'm seeing in the feed issues P07/40 mags and the others with the smaller feed lips.

[M1A4ME]

I grabbed a couple of mine and unloaded them.  I doubt these are the originals that came with the pistol.  I bought several 12 round P07 .40 S&W magazines before it hit me I should be buying P09 magazines for the extra capacity (and to feed the P09 I knew I'd eventually get.)

These two were different, slightly.

mag 1 was 0.3885" at the rear and 0.3900" at the front (measured as close as I could get to where they start to round off and turn down)

mag 2 was 0.3845" at the rear and 0.3890" at the front (measured as close as I could get to where they start to round off and turn down)

Is that what you were looking for?

[Indy_Tim]

I grabbed a couple of mine and unloaded them.  I doubt these are the originals that came with the pistol.  I bought several 12 round P07 .40 S&W magazines before it hit me I should be buying P09 magazines for the extra capacity (and to feed the P09 I knew I'd eventually get.)

These two were different, slightly.

mag 1 was 0.3885" at the rear and 0.3900" at the front (measured as close as I could get to where they start to round off and turn down)

mag 2 was 0.3845" at the rear and 0.3890" at the front (measured as close as I could get to where they start to round off and turn down)

Is that what you were looking for?

Thanks, that's exactly what I was looking for.  It's safe to assume that these mags are working well for you, so I'll check mine again to see how they stack up.

[M1A4ME]

Yeah, they work great.  The only failure my P07 has had in almost 3 years was a swelled up reload I missed when I (evidently) had the bullet turn slightly on seating and it bulged the case.  Then I missed it as I handled it out of the press and into the box/jar/jug (not real particular about how I store my reloads/ammo.

That bullet fed, but wouldn't chamber.  Not a magazine issue.

[Indy_Tim]

Another range trip today.  This time, I ran 70 rounds through the gun with two changes.  I swapped the CGW yellow hammer spring out and reinstalled the factory spring.  I picked up a minute amount of weight on the SA pull but the DA pull is back over 10lbs.  The other change was to stretch the spring in one of the mags.  Overall, there's a big improvement but I still had two FTFs, one with each of the mags.  The mag with the stretched spring had one instance of a premature lock back on the slide and the other mag had 3 instances of the slide failing to lock back after the last round was fired.  The heavier hammer spring brought the brass in about 3 feet, but  it's  still tossing them a good 20 feet.

I'm thinking that I need a heavier recoil spring.  I read that the factory spring is 20#, and it does feel lighter than the 18# spring I got from CGW.  My current theory is that the gun is under sprung and that the mag springs are weak as well.  One one of the FTF, I noticed a ding on the side of the projectile where it looks like it may have impacted the side of the slide stop.  What I think may be happening is that under fire, the slide recoils back hard against the stop torquing the gun back to the right.  As that happens, the round in the chamber is moving to the left as the gun recoils up and to the right.  With a weak mag spring, the bullet impacts the slide stop nose and rebounds down into the mag barrel where it hangs on the front lip.

I don't see any extra power mag springs offered by anyone, nor have I seen a recoil spring rated at over 18#.  With 540 rounds fired this month alone in testing, I'm starting to lose interest in this gun.  I've resolved issues in many guns before, but the cause and fix were generally obvious.  This is the first that just seems like it may be a lemon, but I'll keep trying until I figure it out.  It's sad that as good as my 1st gen P07/9mm is, this 1st gen P07/40 is the polar opposite.  As much as I hate to say, this has me thinking that I'll steer clear of the P10 until it's been proven. 

[M1A4ME]

Now that you mention the slide stop, they are different.  I noticed when I bought my P07 and then bought a spare slide stop for a 9MM P07 top end I bought that the tips (that stick through the frame so the follower can push them up and lock the slide back) were shaped differently.

There's been more than one discussion here about issues with the some slide stops.  Some of them stick too far out and are contacted by the bullet and get pushed up to lock the slide back.  Are you (somehow) holding the slide stop down when you shoot the gun?  If you mentioned the slide sometimes locking back with bullets still in the magazine I missed it.

[Indy_Tim]

I have had at least one instance of the slide locking back prematurely.  I got a new mag in last week and after 100 rounds, only had one feed issue.  This issue was different than the others though and may have been a bad reload.  I have a bad habit of chambering the round and shooting it instead of collecting the round for analysis like I should.  Every previous FTF would stick the nose of the round down inside the mag against the front lip.  This one FTF was a more common 3 point failure to feed.  I need to run 100 rounds of commercial ammo through it before I'll start thinking that the issue is behind me.  I'm thinking about putting 50 rounds through it using the old mags and the slide stop from my P09/40 to see if that makes a difference too.  If so, I'll order a new slide stop to see what that does.

[M1A4ME]

I haven't tried this with P07 magazines, but it works with Beretta 92 magazines.

Load some of your 9MM magazines up with .40 S&W and shoot them through the .40 S&W P07.  I've bought surplus military Beretta 92 magazines (9MM) for my son and he's used them without issue in his Beretta 90-Two (.40 S&W).  The larger diameter rounds sit a little lower in the magazine but the slide still picks them off the top and shoves them into the chamber.  Don't know if that would work in your P07 or not, but it might be worth a try as another way of pointing the finger at the magazines.

I have had magazines (new ones) with "bad" springs.  I replaced all my original P14 (14 shot 1911 from Para Ordnance) magazine springs.  The new ones were made different so evidently PA was aware the original versions had some shortcomings.

Or even put a spring from a working 9MM magazine into one of the malfunctioning .40 S&W magazines.