odd primer piercing

[megasupermagnum]

I've been loading handgun for about 8 years now, and this is the first time I've seen this. I can post pictures if required, but there is not much to see. The gun is an old S&W model 29 .44 mag, silhouette model with about a 10 inch barrel. This is the first time I've loaded for this gun before, but do not remember any problems with the S&W .41 mag with the same primers (I may have to check now). I was shooting cast bullets of an old SSK design, that casted just under 330 grains. I started below starting load at 9.5 grains of Blue dot, and went up to 11. Max is listed as 13 grains, and I never saw a flattened primer, or saw any indication of high pressure. The primers were some older Remington LP standard primers. The odd thing was that it was always 1 out of 6 with a pierced primer. Is it possible to have a bad batch of primers? When I say pierced, the indent simply looked black, and you could see a tiny crack if you looked close. Accuracy was still good, and everything seemed normal. I should mention that this gun doesn't do this with factory ammo.

[billyb]

My first guess is the brass cup of the primer has become brittle. I have had a few primer cup cracks like you mentioned in military ammo from the mid 40's.

[tazman]

A few years ago I had a bad batch of Remington small pistol primers that would pierce with any load heavier than light target loads in 38 special. Every single round pierced when used in 9mm.
Other primers , used with the same load, never pierced or showed other signs.
Bad batches of primers do happen.

[megasupermagnum]

I just wanted to be sure, thanks guys. I'll keep these for target loads, and buy some new primers. I also checked some spent .41 cases, and sure enough some had pierced primers. By the way, I'd guess these primers are from the 90's, but they could be older than that.

[osteodoc08]

Is it always on the same cylinder? Probably a primer issue if also on the 41.

[megasupermagnum]

No it was not always on the same cylinder, but oddly always 1 out of 6 (out of 4 groups). Must have been chance, as the .41 did it too.

[rintinglen]

I bought a sleeve of Remington SP a year or two ago that gave the same result--Pierced primers whenever I went beyond about 17,000 cup. With 38 target loads or 32 S&W loads, they are fine. In a 9mm or a .327, I got pierced primers. Nnot always, but often enough to be disconcerting. So yes Virginia, there is a thing called bad primer lots.