2011 problems...

[MosinVirus]

Here is what I have learned in my quest to make my 9mm 115 grain factory ammo run my compensated gun. Ultimately I had to reduce the weight of the comp to completely solve my cycling issues, but still.... Learned a lot. By the way this is a standard barrel, non-ramped.

My goals were to use standard factory ammo and have reliable feeding, extraction and ejection.

1. Make sure the barrel is not rubbing on the slide when the slide goes back. Basically perform a Schuemann timing test and see if the barrel drops low enough.
2. Reduce the weight of the slide by porting.
3. Use a variable power recoil spring. Basically to allow the slide to move more easily at the beginning of its rearward movement to gain more inertia (to have proper extraction and ejection)
4. Cammer hammer mod is wonderful. Same principal as pushing a door open. If you place your hand as far away from the hinges it is easy, and if you place your hand on the door near the hinge it is super difficult. Imagine the hammer face is the door, the hammer pin is the hinge and the FP stop is the hand. If the FP stop has a low point of contact with the hammer the slide will need to spend more energy pushing the hammer back, if the FP contact point is moved upward, it will take less effort.

Here is what I did to my hammer (this was first attempt and on the wrong hammer with large hole. Since then I got a different hammer with a smaller hole and it looks much better)



The FP stop got a straight (not rounded) slope on it. about 1/3 of thickness on the bottom going straight out to about 1/16" below the firing pin hole.

The bottom edge on the hammer face contacts the slope of the FP stop at the very top, and as the slide moves rearward, the contact point is basically always as far from the hammer pin as possible. I wish you could try racking my slide.

5. Reduce the amount of overcock pressure by reducing the face shown below. This will reduce the amount of friction on the slide as it rides over the hammer (suggested by Wilson Combat rep). It is not shown on this hammer. Like I said this was my first attempt and the wrong hammer for this... I can provide better pictures later. The slide should still overcock the hammer when traveling over it, but the amount of overcock can be reduced.



Ultimately, I was able to increase my recoil spring weight to 12.5lb after cutting the comp down. Here is the gun now. Since I was using plastic follower magazines and a .45 acp slide stop, they started to slip past the slide stop, so don't pay attention to slide not locking back sometimes. And that higher power recoil spring really helps prevent feeding or return to battery issues.

I could have left 2 ports on the comp, but I didn't feel like going through the motions anymore.

Shooting starts at 1:50 of the video.

[dwalker]

Interesting. Would like to see some more detailed shots of the hammer and FPS.

Pretty sure we are on to something here. I am also going to measure the protuberance of the firing pin above the FPS and how thick the FPS is and see if either is on the thick side of spec.

[MosinVirus]

Here are the pics of the 2nd hammer with a smaller hole through it. And FP stop slope. FP stop slope is rounded over on the bottom edge. I have noticed that the top edge of the FP slope should be a little higher than the bottom edge of the hammer face. This way, the rollover happens smoother.





Sorry, it is dirty. Hasn't been cleaned yet after my last range trip.

Bottom line, this was supposed to address my extraction and ejection issues while allowing me to go up in recoil spring weight to address feeding and return to battery concerns.

With .45acp or 10mm, you don't want to take your recoil spring up past 18lb on a gov size (because having the slide slam forward too fast and hard may not allow rounds to go up the magazine fast enough and trigger bounce could be inteoduced), so instead you lower the contact point between hammer and FP stop, by getting a square bottom EGW FP stop and leaving the hammer alone. I have even seen people discussing modifying the hammer face angle to make it go further in past 90 degrees to make it even harder for the slide to come back.

In any case, just sharing what I have picked up through my builds.

[dwalker]

So I spent some quality time with the files, dremel, polishing compound, etc.
First I noticed the surface the disconnector rides on was a bit rough from the cerakoting, so I polished that area back to mirror finish. The disconnector itself I had not polished as I thought it would be "good enough" right from egw. Well I polished it at the top and the trigger bow contact to mirror, polished the egw sear spring, etc. while I was there.
Next was the FPS. Mine was already rounded and polished but I filed it to a more 45deg angle and polished it back to mirror. Gun racks much easier, a definite difference in effort and much smoother.
I also found some smut in the barrel/slide lugs that I suspect is again from the cerakoting getting worn off the slide surfaces as the gun cycles.

Have not made it to the range as yet to test for function but hope to get out tomorrow am and throw a couple hundred rounds through it.

[cooper74]

Interesting that you mentioned the disconnector. On my 2011 build, I used EGW's Koenig ignition kit and on initial test firing, I noticed my slide hesitating on RTB. It would fully return, but I could tell it was getting caught up.

If the return to battery is the problem, I could definitely see how the disco might be what's contributing to that. On my build I felt the biggest difference when I rounded that middle prong.

I'm considering doing the marvel disco slot cut on the slide too... just for kicks and to make the return as smooth as possible

So I spent some quality time with the files, dremel, polishing compound, etc.
First I noticed the surface the disconnector rides on was a bit rough from the cerakoting, so I polished that area back to mirror finish. The disconnector itself I had not polished as I thought it would be "good enough" right from egw. Well I polished it at the top and the trigger bow contact to mirror, polished the egw sear spring, etc. while I was there.
Next was the FPS. Mine was already rounded and polished but I filed it to a more 45deg angle and polished it back to mirror. Gun racks much easier, a definite difference in effort and much smoother.
I also found some smut in the barrel/slide lugs that I suspect is again from the cerakoting getting worn off the slide surfaces as the gun cycles.

Have not made it to the range as yet to test for function but hope to get out tomorrow am and throw a couple hundred rounds through it.

[foxtrotuniformlima]

My bet is on the disconnector / sear / trigger bow arrangement.

Your observation of the surfaces needing polishing is spot on but don't forget that the trigger needs a bit of over travel to allow all that stuff to function. So many shooter try to achieve zero over travel and the result can be a gun that doesn't reset consistently.

Bob has a nice write up on it as well as the other parts of the trigger adjustments http://www.brazoscustom.com/magart/0407.htm

[MosinVirus]

I am no expert, but the way I set my overtake is by adjusting the screw until the hammer can't fall, then turning the screw out until the hammer has no drag on the sear as I hold the trigger pulled back and pull the hammer down and up with my thumb. When there is no drag I turn the screw abother 1/4 - 1/2 turn out. Usually results in pretty reliable overtravel adjustment

[dwalker]

My bet is on the disconnector / sear / trigger bow arrangement.

Your observation of the surfaces needing polishing is spot on but don't forget that the trigger needs a bit of over travel to allow all that stuff to function. So many shooter try to achieve zero over travel and the result can be a gun that doesn't reset consistently.

Bob has a nice write up on it as well as the other parts of the trigger adjustments http://www.brazoscustom.com/magart/0407.htm

The reset was one if the first things I checked, but again the fact that it will not fire when the hammer is hand re-cocked and will not fire until the slide is racked makes that seem unlikely. I believe Mosin virus was on the right track with some additional firing and refining needed. My slide is full weight and that's likely to heavy for factory/gamer 9. It's likely to be reliable now but I will likely need to cut or change the slide to get it to shoot the way I want it to.

[dwalker]

I am no expert, but the way I set my overtake is by adjusting the screw until the hammer can't fall, then turning the screw out until the hammer has no drag on the sear as I hold the trigger pulled back and pull the hammer down and up with my thumb. When there is no drag I turn the screw abother 1/4 - 1/2 turn out. Usually results in pretty reliable overtravel adjustment

My trigger does not have an overtravel screw fitted at the moment. I'm really not worried about the trigger until the gun is reliable. Once it runs 100% iv will pull the Haber and sear and do the trigger job, but for now it is as delivered from EGW.

[MosinVirus]

Wait, so you are still having issues with hammer not falling if you cock by hand?

[dwalker]

Wait, so you are still having issues with hammer not falling if you cock by hand?

Hammer falls gun does not go bang. I really believe the hammer was falling with the gun slightly out off battery so the hammer dies not contact the firing pin squarely.

[ojisan]

Crud in the locking lugs will keep the back end of the barrel low, causing offset primer strikes / misfires.
I fixed a friend's RIA .45 with this problem, there was a blob of what seemed to be epoxy or hardened varnish stuck in one of the slide locking grooves.

[dwalker]

Crud in the locking lugs will keep the back end of the barrel low, causing offset primer strikes / misfires.
I fixed a friend's RIA .45 with this problem, there was a blob of what seemed to be epoxy or hardened varnish stuck in one of the slide locking grooves.

Yeap, I was shocked to find the crud there to, until I realized the cerakote is probably getting rubbed off, mixing with oil and turning into some sort of slurry. Cleaned it out out and it seems fine.

To the range! (tomorrow )

[dwalker]

Whelp, I ran a bunch of rounds through it today doing dot drills and not one issue. Ran like a champ on 124gr target HP's moving about 1050/1100.

I think what was happening was a Failure To Return to Battery completely. The gun would, on a semi full mag or maybe if I limped it, almost return to battery, enough so the disconnector was up, but ever so slightly out of battery so that when the hammer fell it did not strike the FP squarely. Hand cocking the hammer had no effect, because the slide was still out of battery slightly. Only when the slide was racked or pushed into battery would the gun go bang.
So what I believe was causing this is a combination of things. The 115gn UMC ammo may have had hard primers, and might have been a little on the weak side for the slide weight/springs/etc.. The major issues I believe were the disconnector, sear spring, and Firing Pin Stop. The FPS was already rounded but filing the near 45deg angle to it and polishing it to a mirror finish really helped. The disconnector, sear spring, area the disconnector rides on, etc were all polished to mirror. I really think these things had the most effect, because the slide was noticeably easier to rack and felt smoother.
The last thing I changed was the Wilson 10lb spring to a 1911springs.com 11lb spring. Honestly the 11lb spring feels lighter than the 10lb Wilson spring, but at least now there is some confidence the spring rate is what it is supposed to be. I am going to order the "light" spring kit as well and see if going slightly lower, maybe 9 or so, will work.

At some point I am very likely going to have to lighten the slide a bit further, but I will cross that bridge when I come to it.

Anyway, thanks for all the input! It really helped.

[bigbob76]

No, unfortunately during the match I was not able to tell my ejected rounds from anyone elses so was not able to pick them up and even look at the primer or try to make them shoot.

I didn't understand that, were other shooters ejecting live rounds also?

It sounds like the problem is gone now though, right? When I have a problem my most basic thinking is "what is the last thing that I did with this gun?" I remember on one of my STI 9mm pistols the last thing I did to it was to clean it and after that it sometimes wouldn't completely return to battery. I field stripped it and realized I had used grease instead of the oil I usually used on that pistol. I wiped the grease off, used oil, and it was good to go again.