Best Cartridge Designs?

[Alex Wheeler]

Agreed. In F Class, 7PRCW (6.5prc/7mm) also won the South African Nationals, Texas State Championship as well as the Southwest Nationals this year. It also took at least 2 of the top 5 spots at the European Championship this year.

To paraphrase (sorry Alex I can't find your exact quote) @Alex Wheeler, the 7prcw wasn't made to be a magnum cartridge, it was made to be a more stable and longer lifed 284 shehane to which it's done admirably. Brass life is insanely long, barrel life has been great for most using it and tuning is largely easy with a number of powders. It has huge flexibility. I've seen it hammer in the 2700's, 2800's, 2900's and surprisingly I've even seen a few hitting the 3,000's with accuracy although brass life will probably suffer.

Yes, thats about right. The most important part of cartridge design is optimizing the case size. Through testing you find what speed a bullet performs at. At some point if you push them too fast the agg suffers. So if we know a 180 hybrid shoots well around 2800-2950 you want a case that maxes out there. Thats why the BRA and PPC work so well too, they are maxed out. If it was up to me the 7-6.5prcw would be a hair smaller yet but the brass forming op would hurt more than it would help. The shorter powder columns help with consistency. The longer they get the more es and consistency suffers. Thats why the prc case is proving to edge out the 284 for raw accuracy. Probably the perfect cartridge would be a max charge to get you the velocity you want in a round case. But we are stuck with the brass we have. I dont think taper or shoulder angle have a role in accuracy but they do in other things like pressure handling and brass stability. Neck length doesnt play a role either but it does effect throat wear so you could say less wear measure less chasing and staying in tune. We saw a huge difference in the dasher vs bra with throat movement.

 

[NZ_Fclass]

I'm of the (mostly unfounded) opinion that case design is mostly about capacity, and that certain features contribute to quality of life, utility, and brass life. You can make just about any common case shoot really well if it's the right size for the bullet/barrel you're using. A good sharp (30ish degrees) shoulder and relatively straight taper with a long enough neck to avoid the donut are all positive features in my book.

What I don't believe (again, anecdotal) is that within reason the case geometry impacts ignition or barrel life. I would happily be proven wrong on that, but it just doesn't seem to matter.

I agree - but there's further to go. It's not just about the case - It's the chamber, freebore and twist rate that goes alongside.

 

[Will Henry]

I think that most military cartridges are very well designed. The Mauser cartridges are pretty close to perfection. The 7x57, 8x57, the 6.5x55. The Newton cartridges were pretty well designed, and would be fine cartridges even today. WH

 

[Joe Salty]

How about Barrels and Bullets. I know a lot of guys with a ton of different case configurations that shoot lights out.

Joe Salty

 

[Dave M.]

Give it time. It has only just won the World Champs. And there's no SAUM brass.

I suppose but at 1000 yards I think the choices are plenty for rounds that can consistently win.

 

[Dave M.]

Agreed. In F Class, 7PRCW (6.5prc/7mm) also won the South African Nationals, Texas State Championship as well as the Southwest Nationals this year. It also took at least 2 of the top 5 spots at the European Championship this year.

To paraphrase (sorry Alex I can't find your exact quote) @Alex Wheeler, the 7prcw wasn't made to be a magnum cartridge, it was made to be a more stable and longer lifed 284 shehane to which it's done admirably. Brass life is insanely long, barrel life has been great for most using it and tuning is largely easy with a number of powders. It has huge flexibility. I've seen it hammer in the 2700's, 2800's, 2900's and surprisingly I've even seen a few hitting the 3,000's with accuracy although brass life will probably suffer.

I’m running a straight .284 win at 2875fps and it is an absolute hammer and a joy to shoot. In 1000 yard events this year the same rifle and same load have shot 1987 out of a possible 2000 points. Tough to get much better than that, and the barrel wear thus far has been very good.
Dave

 

[Infrequent Shooter]

Look at the 6 XC. That is perfection! Imagine if Hornady had control of the marketing : ) There would be no better cartridge design in history!

I have been told this by some very sharp guys on this forum.

 

[Infrequent Shooter]

Yes, thats about right. The most important part of cartridge design is optimizing the case size. Through testing you find what speed a bullet performs at. At some point if you push them too fast the agg suffers. So if we know a 180 hybrid shoots well around 2800-2950 you want a case that maxes out there. Thats why the BRA and PPC work so well too, they are maxed out. If it was up to me the 7-6.5prcw would be a hair smaller yet but the brass forming op would hurt more than it would help. The shorter powder columns help with consistency. The longer they get the more es and consistency suffers. Thats why the prc case is proving to edge out the 284 for raw accuracy. Probably the perfect cartridge would be a max charge to get you the velocity you want in a round case. But we are stuck with the brass we have. I dont think taper or shoulder angle have a role in accuracy but they do in other things like pressure handling and brass stability. Neck length doesnt play a role either but it does effect throat wear so you could say less wear measure less chasing and staying in tune. We saw a huge difference in the dasher vs bra with throat movement.

been reading that neck length was one of the advantages of 222 rem over 223, and other designs. I do not question your comment re neck length. maybe neck length makes it easier to achieve low(er) runout.

 

[Infrequent Shooter]

Yes, thats about right. The most important part of cartridge design is optimizing the case size. Through testing you find what speed a bullet performs at. At some point if you push them too fast the agg suffers. So if we know a 180 hybrid shoots well around 2800-2950 you want a case that maxes out there. Thats why the BRA and PPC work so well too, they are maxed out. If it was up to me the 7-6.5prcw would be a hair smaller yet but the brass forming op would hurt more than it would help. The shorter powder columns help with consistency. The longer they get the more es and consistency suffers. Thats why the prc case is proving to edge out the 284 for raw accuracy. Probably the perfect cartridge would be a max charge to get you the velocity you want in a round case. But we are stuck with the brass we have. I dont think taper or shoulder angle have a role in accuracy but they do in other things like pressure handling and brass stability. Neck length doesnt play a role either but it does effect throat wear so you could say less wear measure less chasing and staying in tune. We saw a huge difference in the dasher vs bra with throat movement.

shorter powder column>> so would a 25 Souper theoretically be a better(accurate) case than others of close or same velocity/capacity? kicks the hornet nest a little here. looking at a cartridge diagram, the 25 Saum looks to have a shorter powder column of the larger cap cartridges.

 

[jackieschmidt]

In Short Range Group, optimum capacity appears to mean everything.

If it didn’t, then the 6BR could stand toe to toe with the 6PPC, and the 22 PPC and 22BR could stand toe to toe with the 22PPC short.

They aren’t.

The 30 degree shoulder seems to work just fine in the PPC and BR cases.

The short fat thing attributing to extreme accuracy seems to get it’s roots in the PPC. However, its smaller case head diameter is also conducive to minimum bolt thrust, allowing shooters to shoot at extreme elevated pressures and still get the bolt open.

This is a downside in the large capacity short bodied cases. As case diameter increases, bolt thrust increases at a substantial rate. Todays actions actions seem to handle this problem.

 

[kountryboy2]

In Short Range Group, optimum capacity appears to mean everything.

If it didn’t, then the 6BR could stand toe to toe with the 6PPC, and the 22 PPC and 22BR could stand toe to toe with the 22PPC short.

They aren’t.

The 30 degree shoulder seems to work just fine in the PPC and BR cases.

The short fat thing attributing to extreme accuracy seems to get it’s roots in the PPC. However, its smaller case head diameter is also conducive to minimum bolt thrust, allowing shooters to shoot at extreme elevated pressures and still get the bolt open.

This is a downside in the large capacity short bodied cases. As case diameter increases, bolt thrust increases at a substantial rate. Todays actions actions seem to handle this problem.

The late great Ron Holem felt like the length and diameter were as equally important. He felt like the 6 br was just enough larger in diameter than the 6ppc and that was why the 6br wasn't as accurate as the 6ppc at short range bench. He felt like the 6 br also didn't have enough case capability for longer range either. I think he was right. Look at the 6bra.

 

[Forpest]

I'm of the (mostly unfounded) opinion that case design is mostly about capacity, and that certain features contribute to quality of life, utility, and brass life. You can make just about any common case shoot really well if it's the right size for the bullet/barrel you're using. A good sharp (30ish degrees) shoulder and relatively straight taper with a long enough neck to avoid the donut are all positive features in my book.

What I don't believe (again, anecdotal) is that within reason the case geometry impacts ignition or barrel life. I would happily be proven wrong on that, but it just doesn't seem to matter.

Case geometry is quite important for ignition, and the more powder burning in the barrel will reduce barrel life. A good discussion of this can be found in this patent:

https://image-ppubs.uspto.gov/dirsearch-public/print/downloadPdf/7086336

It explains why short fat cases are more efficient and discusses shoulder angle and why some angles work better in some cases. This was developed by a rocket scientist who Designed and studied studied ignition in space shuttle boosters

 

[mauser284]

.308 Norma Mag....just right case capacity, neck a bit longer than one caliber, fits 30-06 length action, very efficient. However 300 Win Mag eclipsed it in short order for a lot of non-performance reasons. Read Ken Waters articles about the case in the Pet Loads book. If you don't have it and shoot a lot you should.

Ken Water's Pet Loads Complete Volume

SLIGHTLY DAMAGED. Ken Waters PET LOADS Complete Volume. This is Ken's monumental lifetime work in the handloading field andcontains loading procedures, tables, tips, precautions and commentary; over 150 cartridgesare detailed. No handloader's library is complete without this comprehensive book...

www.wolfeoutdoorsports.com

My first day with my 300WM around 1994 or 1995 I was shooting at my local range and having a blast. I had not started reloading yet so it was likely 1994. I was trying out every factory 300 Win Mag ammo I could find from 150gr to 220gr. at the range. Normaly outside of competition when I am at a range I am normaly the guy shooting the tightest groups. I look down range through my spotting scope and see these tight little groups like 2 stalls to my right. I get off my scope and up fromt he bench to see who the heck is out shooting me. It is a little old guy mostly bald covered with liver spots with thick glasses and a beautiful rifle. When he is done I walk over to him and ask him what he is shooting. This little old man 75-80 years old tells me 308 Norma Mag and I had never heard of it and he tells me that it is similar to a 300 Win Mag and I said oh that is what I am shooting. It was a sporterized 1903 Springfield with a satin finish blueing on a satfinished oiled walnut stock and a Douglass Barrel. I do not remember the scope know only that it was elite for it's time but definetly vintage. It had very nice sporterized iron sights on it.

I have not come across anyone else that has owned one since then. I was young 20 something at the time. The owner, the cartridge and the rifle made such an impression on me because of the excellence of all of them combined that as a 50 year old I still remeber it well.

I used a paper punch and nails on my home made target ficture so I could track the accuracy of my Broawning A Bolt and I was impressed that everything from 150gr. to 220gr. I was able to keep all groups inside 1.75 inch of each other at 100 yards. Best group was around .6 Moa and the worst was 1.2 MOA at 100 yards but all landed inside 1.75 MOA of each other. That old man with his custom rifle and handloads was putting up clover leaf 3 shot groups as if it was a Sunday picnic! He told me the secret was hand loading and with in the year I had purchased my first reloading equipment.

Even though I have never owned a 308 Norma Magnum it is a fantastic design especially for the time it was brought to market!

 

[mauser284]

All of that said. I am intriqued by this cartridge!

 

[mauser284]

All of that said. I am intriqued by this cartridge!

I have not competed since Covid-19 hit and it damn near killed me. It actual made me diabetic and the 79lbs. I had lost in the 2 years previous I regained. I now have a persistent cough and high blood pressure as well that I did nothave before Covid-19. I am a metabolic mess now.

I miss competting in F Open, NRA High Power, Silhoutte, and Bullseye. I am so out of date and rusty and I know it!

I do like how this site allows me to keep up with trends even if I am late tot he party! God Bless!

 

[BobT]

As far as bigger cased hunting cartridges go I think the 7mm Mashburn Super Magnum is very well designed.

 

[harro]

There are many ways to define “ Best “ .
Most numerous and long lived would have to be the .22lr.
Functional / efficient/ prevalent and probably most utilitarian .223 rem .
Short range accuracy 6 PPC
Long range 1000 yrds etc 7mm bore , you choose the cartridge
Deer slayer 30 cal , you choose the cartridge ( personally don’t like it )
Best general all rounder 6.5 CM , or 6.5x55 ( I own both so I’m biased )
Dangerous/ Large/ Exotic etc has no interest to me .
12 gauge Shotgun ( even though I love the 28ga )

 

[VA_XTC_Shooter]

What I don't believe (again, anecdotal) is that within reason the case geometry impacts ignition or barrel life. I would happily be proven wrong on that, but it just doesn't seem to mamatter.

Draw a line along the shoulder toward the case mouth. If the line is above the case mouth, it will have shorter barrel lid than if line intersected below the case mouth and into the neck wall.

 

[Will Henry]

The shoulder angle combined with neck length thing, and it's relationship to throat erosion, is something I read about sixty years ago. I never saw any reason to doubt it, but I've also seen no concrete evidence to back it up. Plenty of anecdotal evidence and the excessive throat erosion seen in 243 Winchesters certainly points that way. It's all good though. In my 30/40 Krag, that shoulder angle line can about hit twice before it gets out of that neck. I don't load the hunting rifle all that hot, but the two target guns (one one a PGW action, the other on a modified Ruger 77) push 155's right at 3000, and 175's to 2800+. No more than I shoot them, they will never wear out. WH

 

[CJ6]

Case geometry is quite important for ignition, and the more powder burning in the barrel will reduce barrel life. A good discussion of this can be found in this patent:

https://image-ppubs.uspto.gov/dirsearch-public/print/downloadPdf/7086336

It explains why short fat cases are more efficient and discusses shoulder angle and why some angles work better in some cases. This was developed by a rocket scientist who Designed and studied studied ignition in space shuttle boosters

Are you reffering to the SMc cartridges ?