4th Round Eject Problem - SOLVED

I'm having a recurring problem with the 4th round in a five round load failing to eject.  Not every string, but often enough its a problem.   The brass is usually caught between the breech and hood, lying on top of the 5th round, sometimes crosswise with case mouth out.  The problem is not mag specific and extraction itself is not a problem.

Pistol is an STI 1911 with 10# recoil spring.  Load is .45ACP with 3.7gr Vhita Vuori N310 and Magnus 185gr BN or Zero 185gr SWCHP. 

Thought i might be limp wristing, but seems like that would show up on 1st , 2nd or 3rd rounds too.  I'm beginning to think it's something to do with how the 5th round is presenting and maybe dragging more on the slide than the top four rounds. Tried a limited test with loading four or six rounds to see if the third or fifth had similar failures, but have not seen the problem yet.

Thanks for any advice and ideas,

Tom

have you tried different magazines.. also have your extractor tension checked

Magazines is a good guess.

Maybe short stroking with that load? Does the slide lock back every time that the magazines run upty?

The problem is not magazine specific, happens on three different magazines.  Slide locks back on an empty mag, but the last case often does not eject as strongly. 

Thought about short stroking, but can't figure out why it is specific to the 4th - or next to last - round.

Will have to check extractor tension.

Iron sight or optics?  If optics, what mount and dot?  Do you have reduced power magazine springs in the mags?  Are the follower's at the correct angle?  Let's start with those and go from there.

One issue I ran into that gave me fits was a mag catch that was a bit to long. The mag spring would sometimes catch it and slow cartridge lift just enough to throw the loading cycle out of time and screw things up. Few strokes with a fine file and repolish and problem solved

KC.

Burris Fastfire III on the Burris 1911 Novak mount.

Wilson 47D magazines with original springs.  Followers are good as far as I can tell, none are different that the others.

10&Xs,

Mag catch does not seem to be contacting the mag springs.

Tom

Hand your gun, ammo, and magazines to the best shooter you know and see if s/he can reproduce the issue.

john bickar wrote:Hand your gun, ammo, and magazines to the best shooter you know and see if s/he can reproduce the issue.

That was going to be my next suggestion.

John, KC,

Are you thinking I may be contributing with a weak grip?  I thought about that, but figured that would affect other than the 4th/next to last round.

A fellow i talked to this morning thought maybe a 1# lighter recoil spring.  Earlier I had a shock buffer on the guide rod, but took that out and still had the problem.

Will let you know if I find a solution.

Thanks,

Tom

The TAB wrote:Are you thinking I may be contributing with a weak grip?  I thought about that, but figured that would affect other than the 4th/next to last round.

Hard to tell. I can't diagnose the "how", "why", or "what" over the Internet, but my suggestion was intending to take the shooter out of the equation.

I have no idea what's going on with your gun, but I do know that one difference between Sharpshooters and High Masters is that the latter pick up on subtle details that the former miss. No offense intended.

A second set of experienced eyes can't hurt.

John,

No offense taken.  I've been shooting bullseye just over a year and welcome your comments.  The first few times the problem occurred, I suspected I was the problem and paid more attention to my grip.  After several failures always with the 4th round, I began suspecting other causes.  Although I may still be contributing. 

Tom

Shot in the dark..
Check the contour of the slide stop catch that may perhaps be extending too far into the magazine. It can at times make contact with the nose of the bullet as it is feeding upward.
Determine /observe extraction/ ejection without the magazine.

Gentlemen,

Thank you all for joining in on solving my 4th round eject problem.  Early on, jglenn21 asked about extractor tension.  I checked that and found it very weak and the extractor tunnel dirty beyond words.   I cleaned it and reset the extractor tension and have now been to the range a couple of times with no ejection problems.  Correct tension also pretty much eliminated the problem with the last round missing the catcher.

I have no idea why the problem was limited to the 4th round, but correct extractor tension fixed it.

Thank you all,

TAB