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Discussion Starter · #1 ·
I have been following this web site for a while and now have a situation that I can use some help with. I have a Series 80 Colt Commander (all blued steel) that after my most recent range session has given me a new item to be concerned about. For the past few months this pistol has been shaving tiny flecks of brass which I find on the pistol and my hands. I traced this to gouges in the rim of each expended case and decided that someone with more experience than myself should look into it. I took it to a smith in a nearby town, that I have heard good things about, and the diagnosis was my pistol needed a reliability job. Since this pistol has never been reliable with anything other than FMJ ammo I agreed to the work, which was completed. In the time that I have had the pistol back, it will feed the few JHP brands of ammo I have tried, but I have noticed that the pistol still shaves brass. During my last range session I noticed that the rims of my expended brass still had a gouge, but some times the gouge did not go all the way to the front of the rim. This led me to the conclusion that my extractor is possibly too tight, and that I should look into this during my next cleaning.

I found the new item of concern when I removed the slide from the frame. I found that the firing pin was wedged out through the firing pin hole. The firing pin was truly wedged in place, as pressing the firing pin safety plunger did not do anything. In order to free the firing pin I had to remove the firing pin stop, press the safety plunger into the slide and press the firing pin back into the hole. It took a bit of force to free the firing pin. I removed the firing pin and looked at it, and it looked okay, so I reinstalled it, and pressed it forward beyond the safety plunger to see if it would catch again. It did, though it did not take the same amount of pressure to free it this time.

I have examined the firing pin hole in the breech face and it is no longer round. The hole now has a squared edge on its upper surface and there is a dent in the slide above the firing pin hole. I have looked at ten empty cases from my last range session and the primer strikes look deeper than normal, plus there is a raised area on the primer next to the strike that matches the dent in the slide. The primer strike is also the same shape as the firing pin hole. Looking closer at the breech face there are black marks that show the outline of the joint between the primer and the case below the firing pin hole. These marks are not just powder residue, since I rubbed them with a drift and they did not rub away, but they do not feel like cracks either.

After reassembling the pistol, I have not been able to get the firing pin to wedge out by dry firing, so this appears to be at least partially recoil induced. Also the pistol functioned fine during the last range session, all rounds fed properly, so this had to happen after the very last round fired, since I did not have any feeding problems from a fresh magazine. Needless to say this pistol has been retired from use until it is fully checked out, but I have some questions for all of you.

1. Does it seem reasonable that recoil would force the firing pin past the firing pin safety plunger? The ammo I have been shooting for the past 200 rnds in Fiocchi 230 gr. FMJ. I mostly shoot 230 gr. FMJ PMC or Speer Lawman, but always factory ammo. I am using a 20 lb. Wilson spring that has been shortened by two coils. The firing pin return spring was replaced fairly recently, but not with the last recoil spring change, since Wilson does not include a firing pin spring with the recoil spring.

2. Does it seem reasonable that a combination of the firing pin and recoil would dent, or otherwise mark, the slide? Is this indicating a slide problem that will need replacement?

3. Should I take this pistol to Dane, or take it back to the smith that did the reliability job? Dane is about 1/2 hour farther away.

Thanks in advance.
PaulB
 

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Paul,

Sounds like you have a number of problems, either serious, or it is possible,, that none of them are any big deal and easy to fix.

I would take it back to you original smith and show him the problems, have him fix them and test fire the pistol for you.

It is something much easier fixed by looking at the gun and taking the it apart than trying to do it over email.

I would be happy to look at it for you but I am jammed for time on any extra projects till after September. Sorry, hope that helps some.

My guess is John Lawson can fix you up in a jiffy. He is also close by and on this list.

regards,
Dane
 

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Paul:
The pattern of damage to your slide face is due, from what I saw, not to a pistol problem, but to an ammunition problem.
Yet, this is no ordinary ammunition problem, either. The damage seems to indicate a heavy rush of presure in the flash hole of a case before the case head was thrust back against the slide face milliseconds before complete powder combustion, because a primer shot out partway like a piston, then case pressure smashed the case head back and the partially displaced primer dented the slide face.
Sometimes, though rarely, if ammunition is stored in a vehicle primer down the powder will shake and grind tiny particles loose that can settle like dust in the flash hole. The effect of this buildup is almost like a detonation when that particular case is fired. The ammo you used was in the Plus P pressure level already.
You and I replaced all of the parts that were not performing properly and cleared the firing pin channel of its obstruction. Our preliminary range test with standard presure level ammunition seemed to go well. Unfortunately, you did not have any of the ammo that caused the problem in the first place. I would suggest discarding all of the ammo you had been firing and obtain a new batch.
 

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Discussion Starter · #5 ·
This is a follow up to this situation for everyone that is interested. John is correct concerning the overpressure ammuntion. John has now cleared the firing pin from my slide twice. This situation reoccurred after shooting another 150 rounds after he cleared the slide originally. Though the situation is worse than I anticipated, I looked at another pistol that has seen a lot of shooting and it too has a dent adjacent to the firing pin hole.

For everyones benefit the ammo is Fiocchi 230 gr FMJ, rated for 875 fps and 390 ft-lb (from http://www.fiocchiusa.com). The lot number on the partial box I still have is below. I will also post this information in the ammo section of the site.

Lot Information:
CIP 014
4012025-3100

I will post photos as soon as I can get the film processed and scanned.

PaulB

PS. A new slide is on order.
 

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Did you get a chance to chrono that ammo to see if it was way out of spec or anything?

Thanks...
 

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There is no way to chrono on the indoor range close to my shop where we fired the pistol.
This is a pressure problem that might not translate to abnormal velocity; the presure is peaking twice. There is a distinct possibility that the use of rifle primers in reloads will prevent this kind of damage.
I have looked over a great many 1911 slide faces in the last 50+ years, the slides having been removed from the earliest to the latest Colt production, but this is the first time I've seen this pattern of damage.
It would take more sophisticated test instruments than I have ever seen to pinpoint the actual cause. (Most firearms experts simply give educated guesses without scientific proof in situations like this.) Instrumental velocity is not a good indicator. The shooter (Paul) has stated that he was not doing double taps, which might result in partial lockup firing due to a defective disconnector. The timing seemed to be identical to that of my Gold Cup, which has fired a large number of double taps. And, headspace fell within the normal range. My informed speculation was an overpressure condition at the primer. When this lot of ammo was fired in several pistols, the firing pin marks on the spent primers were very deep and distorted to some extent. On the Colt, the damage was opposite the extractor only and deepest on the edge, not radially around the firing pin hole in the slide face. The case head was not distorted from 90 degrees as would happen if the slide face was at an odd angle.
This particular problem has not been recorded in Ordnance Corps or civilian manuals.
 

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Discussion Starter · #9 ·
gyp_c2

It may be a while before I can try to chrono my remaining ammo, as the only person I know with one is on vaction at the momment. I have recently gotten images of my slide and several empty cases of this ammo scanned and I will be posting them on this site. I will post the slide image here and the empty case images in the ammo thread that is running.

PaulB

PS. I e-mailed you one image. I hope the file size was not to big.
 

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Thanks...from what Mr Lawson says, it may be very difficult to pin down the cause anyway...It sure looks weird from those pics though...If you have trouble with the process, drop me another note and I'll post them for you...with YOUR PERMISSION of course...

:wink:
 
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