The web cross sectional area must stand up to the bolt thrust axially combined with the hoop stress radially. The small rimless cases with large primer pockets, like the 10mm handgun and the 30 Rem, cannot take much pressure before the primer pocket gives it up.

The 6mmBR, OTOH, was designed with this in mind, and magnum small rifle primers will pierce as the weak link, and the firing pin holes need to be bushed to go to the next level.

quote:

Originally posted by tnekkcc:

quote:

Originally posted by Kabluewy:

quote:

Originally posted by tnekkcc:

[QUOTE]Originally posted by tnekkcc:
What does it all mean?
It is not easy to find out that the 30-30 case is strong enough for extremely high pressures and the 30 Rem case is weak case only capable of wimpy pressures.

Uhhh - What?
Try saying that again, please, because I'm not sure what you meant?

Surely it's common knowledge the 30-30 brass is designed perfectly well for it's intended purpose and the pressure levels for the Win 94, and Marlin lever guns.

That's the point - exceed that pressure even in a stronger action, and the brass is subject to fail.

It looks confusion will follow you on this topic.

Confusion - what confusion?

Must be that if one stays in such condition long enough, it seems normal.

Seems as though everyone has his mind made up on some subjects, and the relative strength of 30-30 brass is one for me. It would take specific technical proof for me to think otherwise, not someone's private experience using overloads in a tight chamber, and consistantly getting away with it. There's plenty of guys who do that, but I ain't one of them. There are design specs and limitations for a reason. People choose to ignore the obvious in all aspects of life, for whatever subjective reason. That's why they have the Darwin awards, for the extreem cases.

KB

Funny thing. About 2 years ago I was at a gunshow. I ran across a little WesternAuto (Savage) .30-30 bolt rifle. It had an extra clip, looked brand new and the seller wanted $200 for it. It was late Sunday afternoon and the guy looked motivated I looked the gun over and thoughts of reshaping the stock started going through my head. Maybe just using original stock for the begining of a pattern and making it look like a little mannlicher schoenauer and having that duplicated. It was the model that already had the spoon bolt handle and they have the split rear ring reciever. The idea sounded like a lot of fun and would make a neat little brush gun. I didn't buy it but I still think it would be a fun little project.

Terry

quote:

Originally posted by Kabluewy:

quote:

Originally posted by tnekkcc:

quote:

Originally posted by Kabluewy:

quote:

Originally posted by tnekkcc:

[QUOTE]Originally posted by tnekkcc:
What does it all mean?
It is not easy to find out that the 30-30 case is strong enough for extremely high pressures and the 30 Rem case is weak case only capable of wimpy pressures.

Uhhh - What?
Try saying that again, please, because I'm not sure what you meant?

Surely it's common knowledge the 30-30 brass is designed perfectly well for it's intended purpose and the pressure levels for the Win 94, and Marlin lever guns.

That's the point - exceed that pressure even in a stronger action, and the brass is subject to fail.

It looks confusion will follow you on this topic.

Confusion - what confusion?

Must be that if one stays in such condition long enough, it seems normal.

Seems as though everyone has his mind made up on some subjects, and the relative strength of 30-30 brass is one for me. It would take specific technical proof for me to think otherwise, not someone's private experience using overloads in a tight chamber, and consistantly getting away with it. There's plenty of guys who do that, but I ain't one of them. There are design specs and limitations for a reason. People choose to ignore the obvious in all aspects of life, for whatever subjective reason. That's why they have the Darwin awards, for the extreem cases.

KB

I know a physicist that blows various guns up for a study. You'd be surprised at what is though of as brute strong and is not.

My friend decided to do a blowup test on a 1944 round receiver Mosin Nagant. Starting with the normal rifle powders we found out that you could literally dip the case full of ANY rifle powder and shoot the Mosin. The worse we got was a little hard bolt lift. Notice I said little hard. By now this was quite a few shots and not damage. I said quit messing around and do the case full of bullseye like the NRA done on a Jap rifle. We did. Results: jammed the bolt and we had to screw the barrel off. Nothing broke,but there was a slightly noticeable bulge in the barrel in the chamber area. No brass let go. They didn't even blow the primer out. Some blue pills (test rounds) are unbelievably high in pressure. Do you think Mr. Mauser designed his 91, 93, 93, 96, and 98's to take the high pressures of modern cartridges today. Hardly, nothing in that time and age had very high pressures like today. I doubt they had any suitable method to test the strength of their steels used in their rifles. Ever our own 30-06 is running much more pressure then it was originally designed for. Did they change the brass composition much from those days? I'm sure they did. The brass today will take it if the gun is designed right and the chamber is correct.

quote:

Originally posted by gzig5:
Not that it matters to the discussion at hand, but I am pretty sure the 6ppc originally uses the 220 Russian as the parent case. It is the the 220 necked up and blown out. The Grendal takes it another step up in diameter and pushes the shoulder even farther forward.

Pretty sure isn't accurate. That's the parent case alright The 22 PPC cartridge was designed by Dr. Louis Palmasano and Ferris Pindell in 1974. The intention being to design an efficient benchrest cartridge. It was based on the 220 Russian case, which has a smaller head size than the 308 with a small rifle primer, a 30-degree shoulder and necked down to .224 calibre. The fact that the 22 PPC cartridge is winning benchrest matches support the theory of efficient case design.

So they made some changes some noted here and others not like the intention to try match the primer flash cone to the powder column diamter at the base.

A suitable substitute that will certainly hold it's value is a Pre-64 Model 70 in 308. They go for around $1,500.