Odd 1911 malfunction

[mikejonestkd]

Good day all,
I usually only load 45ACp at the lower end of the spectrum, but I am going out with a friend tomorrow so I cooked up some hotter ammo so he can get a feel for full power loads.

The gun is a well loved Springfield Range officer, probably 10,000 rounds though it, and it hasn't failed in the past 2000 rounds or more.

I loaded some light, medium, and hotter loads to try out today so I can load more for the trip tomorrow.

The lighter loads need a 9lb spring so I did a quick spring swap and started with those. 50 rounds fed and shot perfectly.

I swapped springs and put in a brand new wolff 16 pound spring and reached for some 230 gr RN loads that are loaded near max with power pistol. They are stout - and chrono at 920+fps.

In the first three mags with this load i had one round each that failed to feed and literally popped out of the gun as the slide returned to battery.

I put that ammo away, and reached for the medium loads of 200 gr swc with 231 powder. The gun ran though 50 flawlessly.

I ran the remainder of the power pistol loads though the gun and it happened twice again.

So, The gun runs perfectly with mild and medium loads, but has problems with near +P loads.

Any opinions on the cause of this malfunction would be appreciated.

[HiBC]

I have a theory that could be wrong!
You say you have 10,000 rounds through the gun.
How old are the magazine springs?
Tired springs,It might be the recoil acceleration of the pistol is scooting it right out from under the top round in the mag.

That's why they put that little dimple on the follower of the original Colt mags so the last round would not do that.

[mikejonestkd]

HIBC, yes, I was thinking it might be a mag issue but I used one mag for all 150 rounds that I shot today.
The mag is a wilson 47D, and probably a year old, with only a few thousand rounds though it.

The mag runs perfectly in all my other 1911s and worked flawlessly for the light and medium loads today.

The failures were on the 3nd or 4th rounds from the mag, if I recall correctly.

[HiBC]

Clearly,I'm not there,and I don't know.

You have said this magazine worked for all 150 light to medium loads.Check!

I'd say the feed lips,etc are good!

It works in other guns.Check!

You only have bad luck with rounds jumping out (using this magazine?) in this gun with the heavy,hard recoiling loads.
OK.
I can see,and have suggested,that an increase in recoil could cause the cartridge to hold still from inertia while the gun backed out from underneath it.The counter to that would be a stronger magazine spring,IMO.

Of course,experimentation withother magazines or a new magazine spring might really prove me wrong...

But looking at how everything works,and your experience,I'm curious.What do you think it might be?I'm open to learning something here.

[mikejonestkd]

I can see,and have suggested,that an increase in recoil could cause the cartridge to hold still from inertia while the gun backed out from underneath it.The counter to that would be a stronger magazine spring,IMO.

I was pondering the same thing as above, and was also thinking that i might be limp wristing the gun. I am so used to shooting mild loads in 1911s that the hot ones may require a tighter grip. I think I may be the weak link....

I loaded up another batch for tomorrow, and will try again - first with the same mag, and then with an almost new one that I know is 100% reliable.
Thanks!!

[BillM]

920+ is pretty stout. 50ish higher than standard 230 hardball.
It's possible that the 16 lb spring is either affecting the guns timing,
or the slide is hitting the frame hard enough in recoil to partially
eject the top round from the magazine.

You might try a touch stiffer recoil spring---maybe 18 or 20?

[James K]

What may be happening is this. When the M1911 pistol is fired with a hot load, the slide moves back more rapidly than normal. The top round in the magazine will try to stay where it is due to its own inertia. (Variances in bullet and powder charge weight also play a part.) The round thus actually pulls itself out of the magazine lips and tries to pop out of the gun under pressure from the magazine spring.

If there is no "tit" on the magazine follower (often omitted by modern magazine makers), the round moves forward and pops up under the push of the magazine follower, creating the condition described.

Jim

[mikejonestkd]

I am going back to the range today with my friend, and will report back to you if it happens again.
I loaded another batch of the almost +P ammo that had issue, and another 50 with the charge reduced back to normal full power level for comparison.

[4V50 Gary]

Timing.

Methinks the slide is travelling too fast with that extra heavy spring and fast enough such that the magazine cannot feed the fresh cartridge reliably.

[mikejonestkd]

A followup:

I ran 200 rounds through it today without a hitch. no issues at all for any of the three loads I ran though it, including the hotter power pistol loads that had issues yesterday.

I think operator error was the cause, i am going to lodge a complaint with myself.

Three things were different for me today:
1. it was 15 degrees warmer
2. I did not wear bulky shooting gloves today
3. I held the gun much more firmly today than yesterday with the hot loads.

Thanks for the feedback guys!

[HiBC]

All good,and glad its working for you.
Question: Was your grip the only variable you changed,or did you try the different magazine?

[mikejonestkd]

I used the original offending mag, and a new one. Neither one had any problems with any ammo I tried.
I was not wearing gloves on Sunday. I think this was a significant factor.
I was focusing much more on my grip on Sunday than I was on Saturday.

[armedleo]

You mention that it hasn't failed in the past 2000 rounds fired.

So, prior to that last 2000 rounds, how many failures and what kind?

Ammo related?

[RickB]

When I was doing .45 Super load development, the gun ran great until I got to about 1100fps, when I got some last-round, live-round stovepipes.
I was shooting five-shot strings, and as long as I loaded seven and shot five, the gun ran fine.
The springs were just weak enough that they couldn't withstand the additional inertia effects of the heavy loads and heavy springs as the mag neared empty.
I've had the same issue, one time, with standard .45 ACP loads, and in that case the problem was slightly spread feedlips no retaining rounds sufficiently, resulting in a couple of live-round double-feeds.
If the mag tubes are in good shape, clean the mags thoroughly, no lube, and new springs.

[Unclenick]

In this case, though, it was third or fourth round failure, if I read it correctly. I suspect that is due to the spring and the weight of the remaining rounds getting into a bounce that compressed the magazine spring and its return to position with the remaining weight was just right to throw the top round out, which by then may no longer even have been parallel with the others, but could actually have been pointing up and through the front of the mag. Stranger things have happened, and I suspect anything that changed the timing might have stopped that process. Stiffer hold, stiffer recoil spring, recoil buffer, square or at least square-er bottom firing pin stop, stiffer main spring, etc. Just something to throw the timing or the strength of the recoil impulse off.

[mikejonestkd]

A quick follow up. I have been back to the range three or four times with the same gun, magazine and hot power pistol loads. I have run about 200 of them though the gun since the problem we first encountered.

The problem has not happened again, I am chalking it up to my grip and the gloves I wore the day that I experienced the malfunction.

[michaeldarnold]

I would try going back with the gloves and a tighter grip, see if you have any malfunction. Me thinks you won't.

Mike in STL