Problem with S&B primers

I am completely and utterly befuddled with some S&B primers that I have been loading. Have been using S&B for several years now and have never had any kind of problem whatsoever. So last week I developed a load for my G42 using primers from an old lot number and HP38 with a 100 grain flat nose bullet I got from RMR. Test loads worked perfectly so I loaded up about 600 of these, but with primers from a new lot number. When I got to the range, I got failures about 4 out of 7 rounds, or more. It appeared to be light strikes, so I tried it in another of my G42's and got the same failures. After 3 mags with 10 failures I went to another group of bullets loaded last year. All worked perfectly in either gun.
So I start to analyze what is going on. I ran out of primers that I had bought in 2016, a lot of 10,000, so I switched over to a new lot number that I bought just before Christmas. The new lot has tape over the ends of the big box of 1000 and each 100 pack also has tape over the ends. The old lot number did not. So that is one way to tell they are from a different lot.
So here is where it gets befuddling. Skip to a 9mm load. I loaded some 9mm with one of my hand casted 147 grain bullets coated with Hi-Tek, which should make no difference. Worked fine. The primer doesn't really care what load or bullet you have, it should go off if seated correctly, I assume. Ha ha. Well if I'm not mistaken, I loaded 50 rounds of 9mm with the 100g bullets with the new lot of primers and they all shot fine at the range last week. So today I load 5 with primers from the new lot and only about 1 out of 5 will fire. Then I load 5 rounds using CCI primers and all 5 fired. It appears I have bad primers so I load 5 with the S&B primers 9mm but using my 147grain and they all shot. What the heck? Only thing I haven't done yet is use the CCI with the .380 load and 100gr bullet.
The failures seem to be with the 100gr bullet and the new lot of S&B primers in either caliber, which just doesn't make any sense at all. All the rounds pass the plunk test and the primers are seated completely.
My main concern is not only the 600 rounds of .380 that is having failures, but also another 900 rounds of 9mm that I loaded from the same lot. But the 9mm seem to be working.

I took a picture of some primers from both lots and this what they look like.
Green ones are from the new lot and blue ones from the old. The green ones seem to have an odd shape to me. May just be my eyes.
Somewhere along the way it appears they changed the primer compound because of the color.

Blue68f100 said:

Are you sure there Pistol primers and not Rifle?

Click to expand...

S&B are listed on box for both rifle and pistol.
I just loaded 5 rounds each with CCI and the new S&B and the CCI go bang and 4 of 5 with the S&B fail.
I'm loading on a Dillon 650. Been loading for 5 years the same way. Just recently changed from a 95 RMR to a 100RMR. Have shot over 1000 of the 95 grain without a problem. It seems I ran out of the old lot number of S&B about the same time I decided to shoot some of the 100 grainers.
I'm going back to the shop and load some of the 95 with the new lot primers.

Maybe the primer cups are just a tad harder than the old ones. Primers seem to have a good dent in them.

Just loaded 5 rounds with a different bullet and 4 of 5 wouldn't fire. Ran them through 1 gun twice and a different gun one more time for a total of three cycles. Has to be the primers.

captain awesome said:

Do you have a different 380 to run them through? It sounds a lot like a combo of the 380 striking primers lighter than your 9mm, and harder primer cups than the last batch. But that's just one theory/possibility. Is this the same 380 brass you have loaded and successfully fired through your 380 before?

Click to expand...

We have 4 G42s between my wife and I. I shot them through both of mine. This is the same brass I have used several times before.

Fine Figure of a Man said:

What does it say on the 100 piece packages?
View attachment 827217

Click to expand...

Well, I think y'all have solved the mystery. I dug some boxes out of the trash and they said small pistol on the box. All the new ones are marked Small Rifle. From what some reloading friends have told me, small rifle will work in a pistol but have harder cups. So this must be what my problem is. I ordered these from Cabela's back in December and what they sent were the small rifle as marked on the box like in post #16. Boxes look the same and I didn't even notice it since the box says for rifle, pistol, or revolver. Now I'll know not to use these for the .380 but they seem to work in my G26 just fine, at least so far. I'm not really sure about the other 1200 or so I've loaded. I can use them in practice cause I don't want to try them in a pistol match.
Thanks for clearing this up for me.
And from what I understand, S&B primers are no longer available in the US. That's a shame because until this mixup, I never had any problems with them and they were sometimes $19.99 a K around Christmas time.
One friend of mine has been using the Fiocchi brand and really likes them. Maybe I should stick to Winchester and CCI.

captain awesome said:

I would say that's probably your answer, the g42s probably all hit the primers with the same or close to the same force. Probably not enough to reliably set off rifle primers.

Click to expand...

I did order an Extra Power striker spring from Wolff last week just to see if that would help. It has shipped so hopefully it will be powerful enough to ignite these 600 plus rounds I have loaded.
When I did my test loads, I used a few that I had in a partially empty box and they happened to be the old ones that were obviously marked Small Pistol. All the boxes look the same but I just was NOT paying close enough attention. This one is definitely on me, as much as I hate to admit it.