Weak case or Double charge

[bert304]

Yes the mag was damaged so I put it the contanier with the broken grips and the 2 cases. I won't be using it again. So I may not have seated the primer all the way in to the pocket. Thats kinda what I was thinking and the shock set it off.

[roland]

I put my reloads into plastic cartridge boxes with the bullet side down, that way you can give a quick look oveer them to see if their are any problems with the primmers, sometimes are upside down or they fall out, and that they are generally the same length, all the bases are flush or in the same plane.

[bert304]

I do the same thing They were stored bullet down in a 45acp plastic box. The only good thing is I only have 200 left in boxes to check.

[Joe]

Used to see stuff like this all the time with IPSC shooters in the days of unsupported 38 super barrels. From the shooters description, the key is the case in the chamber was bulged at the bottom rear on firing. It bulged because there was hugely, way too much pressure in the case from too hot a load. As the the ejection cycle started the barrel moves backward driving the bulged case with it and helped by the extractor. (I bet there is also a damaged rim on this case where the extractor tore loose, a big sign of excessive pressure in a 1911.) The bulged case catches on the bullet nose of the next round to feed at the top of the mag. This drives the the round in the top of the magazine back very forcibly until it hits the back of the magazine and the frame. Every 1911 mag I have ever seen has a welded seam up the center of the back. It doesn't have to be rough just a little higher than the surrounding sheet metal. As the loaded round is driven back the base deforms briefly until the primer impacts the seam causing the primer to detonate and set off the powder. A high primer would make this even more likely to happen. Because this case has virtually no support it blows out the weakest spot (the side of the case & the primer), taking the grip panels with it, but leaving the bullet in the case. He's really lucky that he didn't have hard plastic grips or he would be having a conversation with a surgeon to get the pieces out of his hand.

Cure:
1) Double check the weight / volume of the load you are using.
2) visually verify powder level.
3) Seat your primers to the correct depth.
4)If a primer doesn't seat completely right, get rid of it.

[bert304]

Ok so it sounds like I double charge the case. Could be, I think I am going to take apart and dump the rest in the group.
JOE does it do any damage to the gun besides the mag getting damaged?
I found a local gunsmith I am going to take it to just to be sure. If he finds anything, I will ship it to Springfield Armory.

[Joe]

Yes that much pressure can do a lot of damage. Have your smith check the lower lug and link thoroughly. Look for cracks in both especially at the point the lugs join the barrel. If the blow out was big enough you could also have possibly sprung the frame and slide, damaged the rails, slide stop,extractor,ejector, top lugs. Any or all. Best to have it completely checked out before you do much with it. If you shear the lower lugs its a nasty SOB to get the gun apart without causing more damage.

[bert304]

Well I had 84 rounds left in the box out of 100, I pulled 34 random cases and took them apart. I scaled each one and inspected the cases, The charge was 5.3 to 5.5 grains which is ok because I was going for 5.4 grains. I took the gun to a local gunsmith and he check it and said it probaly a weak case. He was nice and did not even charge me for his time. If the roads are clear I am going to take it to another gunsmith tomarrow just to be sure.

[Joe]

Glad your gun wasn't damaged. Never heard of a "weak case", sound like "I'll be damned if I know. . All it takes is 1 dbl charge though. On stuff I'm bulk loading I always try to use a powder that fills the case enough that a dbl charge will overflow the case. Using Bullsey always gives me the heebie-jeebies and I use extra caution.

[bert304]

I have heard of cases splitting right at the base where this one blew out, but that is normally with rifle cases that are shot with hot loads. I guess it can happen with any brass. I shot these cases before with power pistol in them and that is a some what of a hot load. Maybe I did double charge only that one. I am going to scale the rest of them to see if any are heaveir than the others.

[RJH245]

So what happened? Is your gun ok? Are you still shooting it? What do you think was the cause of the problem?