But But But But But
Primers cratering even after spring replaced/ Rem 700-223
- Thread starter ACES&8S
- Start date
- Status
It is too large, will try to get a photo of it tonight.
My first though was it was the reloads but we tried a few factory loads and got the same results.
It is doing the same thing with all factory ammo we tried.
Odd part about it is, we were shooting some rifles and my son noticed the cratering and we looked at all my fireformed cases about -20 or so- for the rifle.
Like many of you have said, it has always done it but with them being in one container we couldn't tell if it was progressive or not because
some were only slightly cratering and ok to look at, but some were definitely into the concerned level, epically the ones I had just fired.
This is where it gets paranormal - just kidding - I didn't get 4 more shot done for comparison and it went completely into light strikes
which wouldn't crank another round, not one more.
What are the chances of noticing it just before the spring went out!!! Well, I usually look at the cases but had gotten lax lately, been shooting
a lot so I let it slip and this rifle had always done perfect. But my oldest boy is a stickler for details and grabbed them out of the air for inspection.
We also thought the reload primers were the problem at first.
Yep, cci #400 box # 162014H from the case #162014A. = the date bought and the letter for the 100 card.
My way of keeping up with every case and every card of 100 even by date, in case a case has some defective
primers or they were handled badly after shipping. It has paid off 2 times in all these years but worth the effort.
But the reloads weren't the only cratering, the next 4 rounds were various FACTORY ammo, then it went to light strikes
and wouldn't fire any more.
Nature Boy
Member
- Joined
- Apr 21, 2015
- Messages
- 8,244
They will all crater if you have slop between the firing pin and hole but the CCI 400s have a higher likelihood of piercing if used in cartridges that generate over 40,000 psi. That risk is greater if you’re also cratering them, a lesson I learned…..
You aren’t blanking your primers but @Pivot Dr is.
Everyone should read this article on primers
https://www.accurateshooter.com/technical-articles/primers-and-pressure-analysis/
You aren’t blanking your primers but @Pivot Dr is.
Everyone should read this article on primers
https://www.accurateshooter.com/technical-articles/primers-and-pressure-analysis/
They will all crater if you have slop between the firing pin and hole but the CCI 400s have a higher likelihood of piercing if used in cartridges that generate over 40,000 psi. That risk is greater if you’re also cratering them, a lesson I learned…..
You aren’t blanking your primers but @Pivot Dr is.
Everyone should read this article on primers
https://www.accurateshooter.com/technical-articles/primers-and-pressure-analysis/
Pardon my ignorance, but what is blanking my primers? I’m running right at .0015 headspace with my rifle. It is chambered in 260 Remington improved. I have large primer brass in Lapua, Hornady, Peterson, and have formed most all other kinds of 308, 7-08, and 243 with no issue whatever. I found a deal on some Peterson 260 Remington small primer cases, that’s when my trouble began. I prefer RP 7-1/2’s so they were the first to show problems, next S&B small rifle, same thing. Moving on to WW and Federal Small rifle primers. Finally I loaded some with the CCI Mill spec small rifle primers. Same thing. I too tried a heavier firing pin spring with no change. I go back to any piece of large primer pocket brass and I’m back to normal looking fired primers. I guess until I figure out what is happening and find a remedy I’ll just keep using large primer brass and maybe use the ones not fire formed yet for something else, 243, 7-08, or 308. Seems strange to me but something repeatable is obviously going on here.
Hmmmmm?
Compare your case capacity. The srp brass might be lower. I see cratering like that on several Remington rifles I've reloaded for. All did it with factory ammo. Mag primers aren't as bad about it.
Nature Boy
Member
- Joined
- Apr 21, 2015
- Messages
- 8,244
Blanking = Piercing
Leaving the cratering aside for the moment, can you tell us what small rifle primers you are piercing?
If they are CCI 400 or WSR then don’t use them. The cups are too thin to use with high pressure cartridges like the 260 Rem
So do you think an oversize firing pin might be large enough to take up space and remove the slop?
I don't know these things.
See my answer above your photo of cratered primers, it started with the cci #400 and when I went to factory ammo -which cratered 3 shots-
it stopped firing on the 4'th shot because the spring let go and it was only slightly touching the primer after that.
Tried to take a good photo of the bolt face but no good.
Measured inside the firing pin opening, it is .080".
I need to look up what size the pin is.
I have considered getting an oversize firing pin because the -pilot hole- is too large and seems to have always been my
problem. That idea can change however, with the feedback I get from here and from my gunsmith.
I have so many extra parts for so many possibilities, for rifles and revolvers, I have had to organize them.
Don't need to keep this gathering nest material, got plenty as it is but then things like this come up that
I know nothing about.
If you read my post you will see which primers I’ve used. RP 7-1/2, (my first choice). S&B, WW, Federal, and the CCI Mill spec. (I don’t recall the number just this second, white box, thick cups) for AR type rifles. Why no large primers pierce but any small primers do? Same brand of brass, i.e. Peterson. Got to have something to do with internal physics during firing the cartridge. I’ll form a few that haven’t been fired yet and make say. 243 or 7-08, 308 out of them and see what happens. One is a Sako, one a Remington 700, and one a Springfield M1a. I’ll see what happens then.
Nature Boy
Member
- Joined
- Apr 21, 2015
- Messages
- 8,244
Because the cups are thicker.
Also, most rifles that are designed to shoot small primers have a smaller diameter firing pin. Don’t recall the dimensional difference but I’ll bet your rifle has the larger pin
Never heard about smaller firing pins in say my 222, or 223. You’ve got my curiosity up now. I’ve got both Sakos and Rugers that are chambered in both small and large primer cartridges. Won’t take long to find out wheather mine are different or not.
This rifle is a change barrel. Originally a 22-250, next a Wildcat 22 based on the 308, then 22Br, now the 260 Improved. Never had a problem until now with Peterson brass. Maybe I can find some other brand 308 family small primer brass and see what happens?
Nature Boy
Member
- Joined
- Apr 21, 2015
- Messages
- 8,244
@Pivot Dr
Like a lot of failure modes, it’s usually a combination of several factors that contribute to blanked primers.
For instance:
Firing pin slop to hole and/or weak firing pin spring = cratering.
then
cratering + CCI 400 primers + higher pressure = blanked primer
or
cratering + any small primer + higher pressure + large firing pin = blanked primer
I would doubt it’s the brand of brass but you could buy a box of Lapua Palma 308 and give it a try.
Good luck in isolating the variables. Let us know what you find.
Like a lot of failure modes, it’s usually a combination of several factors that contribute to blanked primers.
For instance:
Firing pin slop to hole and/or weak firing pin spring = cratering.
then
cratering + CCI 400 primers + higher pressure = blanked primer
or
cratering + any small primer + higher pressure + large firing pin = blanked primer
I would doubt it’s the brand of brass but you could buy a box of Lapua Palma 308 and give it a try.
Good luck in isolating the variables. Let us know what you find.
jdsingleshot
Member
This image shows the primers of two cases that were fired with the same
light cast bullet loads. The gun is a Remington model 93 that I fitted and chambered a .30-30 barrel to. One case was fired with the original firing pin. The other was fired after the firing pin hole was bushed and fitted with a new pin.
light cast bullet loads. The gun is a Remington model 93 that I fitted and chambered a .30-30 barrel to. One case was fired with the original firing pin. The other was fired after the firing pin hole was bushed and fitted with a new pin.- Status
