9mm overload

[joem]

This past Sunday at the range a fellow shooter had a incident where a 9mm had a case head failure. It almost blew of the grips off but the pistol held together. All he got was scorched fingers. It looked to me that the rounds were pretty hot from the get go. After he found he lost no fingers and tried another pistol, I gave him three on my 9mm reloads, chrono'd at 1050 FPS. The recoil was noticeably reduced. He said he was going to pull down the rest of his reloads and start over. LUCKEY! :icon_salut:

[Hefights]

Were there any other signs like flat primers? Were the bullets seated to correct OAL after chambering? Older 9mm cases reloaded many times can get weak and lose their tension, causing bullets to seat deeper upon chambering. In 9mm that can raise pressures. However I would think that would not happen on round, but could.

Many of the commonly refered to pressure signs, like flat primers, can be deceiving. However consistently extra heavy recoil and a blown case would be pretty definitive.

[joem]

I did note that there was increased barrel flip and a loud reports on previous shots. Another guy noticed what seemed like excessive recoil but that's a judgement call and he was at the other end of the range.

[p246]

My 9 reloads with 115 grain plated bullets run 1050 over my chrono. I did startt toss in brass after 4 reloads because I felt neck tension was waning. 9m is not near as forgiving as 45ACP is to reload in my experience. Glad no one was damaged beyond repair.

[da gimp]

I've reloaded my practice ammo brass over 10 times in 9mm para, using a moderate load of Unique powder under a 11 gr truncicated cone lead bullet, loaded to just under 1000fps. We segregate all brass, into duty brass (new, 1ce fired) & everything else practice brass..... but still separated.......

[p246]

I probably should seperate my brass, as its all mixed stuff. I might get more loads out of the better stuff. Right now I have lots of the stuff so I guess Im a little lazy there.

[win308]

I'm guessing a primer was not fully seated and the slide set the round off before being fully in battery. I load 5.4 gr Unique under a plated 124 gr fmj, which is hot enough to cycle all my 9s without flatening the primer.

It seems unlikely to have a case head seperation in a 9mm even with a hot load....most straight walled hand gun brass fails from splits at the case mouth from belling out, then crimping the brass...... over and over.

[Tuna]

If the bullet were to be forced into the case as it was loaded into the chamber the pressure will increase a lot when fired. I have had that happen with a Browning Hi Power shooting a reload in an old Browning case that had been reloaded quite a few times. The case let go at the head just forward of the extractor grove and the recoil was much more then expected. No damage to the pistol but the case was tossed a long way from where I was standing. In checking the rest of the reloaded ammo I found one other Browning case that I was able to push the bullet into the case. All the other mixed cases were fine.

[joem]

The case head failure I talked about didn't exit the gun. It was jammed in tight and when he finally got the slide open the case head was almost ripped off. The three rounds I gave him were fired and he could definatly tell there was a great difference. I suspect a double load.

[Tuna]

That's called case head separation and is what happens with rifle cases most often. But in a pistol like that is almost unheard of. Must have been some violent recoil with that and your right he was very lucky.

[joem]

"Must have been some violent recoil with that and your right he was very lucky".

It was excessive and the report was quite loud. I think it was only his third shot. The slide was really jammed tight.