Trying to figure out what when wrong with my reloads. I had loaded up 50 rounds of 40S&W and 50 rounds of 10mm the night before.
The 40 was a load I have shot about 50 or so rounds with no problems. It's a 140 grain lead round nose loaded to 1.125 oal with 6 grains of 700X. Got the data from: http://data.hodgdon.com/cartridge_load.asp They don't list the exact bullet, but it should still be close to a starting load according to them. Chronographs out of my Beretta 96 at 1170fps. No signs of high pressure with any of my brass out of any of my guns.
My 10mm load was a 200 grain lead flat point loaded to 1.250 oal with 5.8 grains of 700X. This is the Lyman listed max and did 1090fps out of my S&W 1076. I had only shot six rounds of this load previously having worked it up from the starting load of 4.4 grains.
So I took this ammo to the range along with a bunch of other guns I was shooting. When I go to the 40, on my fourth round I felt a gust of hot gas in my face and noticed that the gun had jammed. If you look at the first picture below you can see that it took the back end of the case off right at the extractor groove. It knocked the transfer bar part way out of the frame, but did no actual damage to the gun. I disassembled it and checked everything when I got home.
Switching to the 10mm I had shot a few mags through it when on my 16th round had a similar experience as the 40. The case blew out right where the feed ramp is. Only thing it did to the gun was knock a spring loose from the decocker.
It was pretty obvious with the 10mm that I was just running to hot of a load. About half of the brass that I shot has a visible bulge where the feed ramp is. The 40 is the one I was going to ask about, but I think I figured it out while writing this. Looking at my notes, the oal seemed a little long. I had originally developed a load with this bullet for my HK USP. The ammo drops freely into the chamber of the USP, but not in the Beretta. I'm pretty sure that the Beretta fired out of battery.
My plan now is to work up a new load for both calibers. The 40 with the bullet seated deeper and with the 10mm I'm switching to Blue Dot to try to get more velocity at a lower pressure (I'll watch the brass a lot more carefully this time).
The 40 was a load I have shot about 50 or so rounds with no problems. It's a 140 grain lead round nose loaded to 1.125 oal with 6 grains of 700X. Got the data from: http://data.hodgdon.com/cartridge_load.asp They don't list the exact bullet, but it should still be close to a starting load according to them. Chronographs out of my Beretta 96 at 1170fps. No signs of high pressure with any of my brass out of any of my guns.
My 10mm load was a 200 grain lead flat point loaded to 1.250 oal with 5.8 grains of 700X. This is the Lyman listed max and did 1090fps out of my S&W 1076. I had only shot six rounds of this load previously having worked it up from the starting load of 4.4 grains.
So I took this ammo to the range along with a bunch of other guns I was shooting. When I go to the 40, on my fourth round I felt a gust of hot gas in my face and noticed that the gun had jammed. If you look at the first picture below you can see that it took the back end of the case off right at the extractor groove. It knocked the transfer bar part way out of the frame, but did no actual damage to the gun. I disassembled it and checked everything when I got home.
Switching to the 10mm I had shot a few mags through it when on my 16th round had a similar experience as the 40. The case blew out right where the feed ramp is. Only thing it did to the gun was knock a spring loose from the decocker.
It was pretty obvious with the 10mm that I was just running to hot of a load. About half of the brass that I shot has a visible bulge where the feed ramp is. The 40 is the one I was going to ask about, but I think I figured it out while writing this. Looking at my notes, the oal seemed a little long. I had originally developed a load with this bullet for my HK USP. The ammo drops freely into the chamber of the USP, but not in the Beretta. I'm pretty sure that the Beretta fired out of battery.
My plan now is to work up a new load for both calibers. The 40 with the bullet seated deeper and with the 10mm I'm switching to Blue Dot to try to get more velocity at a lower pressure (I'll watch the brass a lot more carefully this time).