"Modernizing" older cartridges?

[Bidwell]

The “Hornady Sauce”/modern design 308Win would be the 30 T/C which is the parent case for the 6.5 creedmoor. The secret sauce isn’t necessarily the tight twist or heavy bullets; it’s the leade angle/throat diameter/throat length.

Sammi 308 is very sloppy in the throat. It needs to be. It was designed for use in machine guns. 30-06 is much the same. Some rifle builders have improved upon this with custom reamers (I.e 30-06 Serengeti reamer) but getting around sammi in a factory gun would cause problems.

So if you’re looking for a “modern 308” you missed the bus with the 30T/C or you need to go custom

I had never heard of the 30 t/c. An interesting mini rabbit hole I just went on. Caries a lot of the design improvements in the 308 I was sort thinking about. It's a 30 creedmoor. Sounds like it relied on some special sauce powder to get the velocity improvements, I can see how that would impede acceptance, amongst other things. From what I was reading, sure sounds like they had high hopes for it.

 

[TaperPin]

Dipping a toe in the benchrest and accuracy forums can provide a good education on what extent things actually effect accuracy. When guys made the move from 6BR to 6BRai, it wasn’t right away. Not until shooters could provide real world benefits did it take off. It could be argued unless your rifle is capable of well under 1/4 MOA groups, the benefits of a creedmoor or AI shoulder annd body taper are moot. Reamer clearances are a book in themselves, but most of the hard stuff has already been figured out.

 

[Bidwell]

Cartridge design is really interesting, and learning about the history of how designs have evolved gives a person a new appreciation for the good and bad aspects of new designs. The idea of updating cartridges isn’t new, but the idea that updates have to be offered in factory rifles and have readily available ammo is. Just a few decades ago many more serious shooters were reloaders and a cartridge to duplicate the performance of something like the 6.5 creedmoor is as simple as ordering a 260 Ackley Improved fast twist barrel and getting a set of dies. The 22-250AI in a fast twist barrel does everything a 22 creed can and has for quite a long time.

Barrel manufacturers that also install barrels often have multiple options for popular cartridges and throats can be set for any bullet you want. There are a lot of benefits to fine tuning a custom reamer to meet your needs and have a barrel chambered with your reamer rather than whatever a gunsmith has - it’s very close to having a pizza made with the topping combinations you want vs the meat lovers, or six other combinations listed on the menu.

Not everything about straightening out body taper and increasing shoulder angle is an actual improvement. Every month someone posts a problem rifle that has clickers with normal pressures - a common problem when body taper is minimized. The 300 PRC is so problematic the Alex Wheeler reamer to add more taper to the chamber walls is a defacto standard with many gunsmiths. The fat shoulders don’t always feed great in factory double stack internal magazines and it makes tweaks to the magazine spring more common. Traditional designs feed great and rarely cause clickers unless the pressures are too high.

The more someone learns about past and present cartridges, the more obvious it becomes that marketing drives the popularity of many modern designs, and they aren’t really better than past options, but simply more convenient. Marketing money is also responsible in part for the downfall of reloading - ammo sales are much more profitable than components.

I was well into my 30s before realizing the majority of reviews, ads, and testimonials that drove my purchasing decisions were backed with marketing $$$$ and many competing brands were as good or better. It’s big business.

Solid points. I didn't realize some of the prc offerings had those issues, but it makes sense. I've sort of been tempted to take a metal lathe and gunsmith class so maybe I can make a wildcat some years from now when I have more experience.

 

[180ls1]

sort of like a 308 v2.0. Would there be a market for something like that, and what would you do to squeeze out a little more "inherent" accuracy from it? It seems like new cartridges come out at a pretty decent rate, relatively, but there's never refinement on past versions. Which is sort of unlike any other product.

Its a massive liability *when* (not if) users mistakenly interchange the ammo and cause serious harm to themselves. Why is 12g and 20g different colors? People still screw that up.

Other products are less consequential in that regard.

 

[Bidwell]

Its a massive liability *when* (not if) users mistakenly interchange the ammo and cause serious harm to themselves. Why is 12g and 20g different colors? People still screw that up.

Other products are less consequential in that regard.

This thought actually crossed my mind. It's a good point

 

[Sundodger]

I've read a little about how more modern cartridges are designed with tighter tolerances and other "accurizing" attributes than say something like 308 win or 30-06.

I know the 308 maybe isn't the best at anything in particular but I like the versatility, barrel life and its pretty darn accurate as-is. But that said, it was designed in the 50's and there doesn't seem to be anything out there that's basically the 308 but with some of the modern cartridge advancements, sort of like a 308 v2.0. Would there be a market for something like that, and what would you do to squeeze out a little more "inherent" accuracy from it? It seems like new cartridges come out at a pretty decent rate, relatively, but there's never refinement on past versions. Which is sort of unlike any other product.

I know that if you create a custom rifle you can decrease tolerances and increase accuracy/precision. As a reloader I'd be curious to learn more about how'd you'd go about working with a gunsmith to create a rifle for a specific projectile and brass cartridge as well.

30 TC is a modern 308, mostly... I think it's pretty short so you can prob put a longer bullet in there without too much fuss,

Neck up a 277 fury hybrid case to 308 and that would be a modern 308 AI. If you want longer bullets custom dies and trim it short or put it in a LA.

 

[Macintosh]

I may move up to the wsm at some point but it's hard to justify since I won't be shooting anything larger than a deer for the foreseeable future, and I wont be shooting past 400 yards. The 308 sort of fits this kinda funny gap with copper bullets. Within around 400 yards, it hits harder and has higher muzzle velocity than a 6.5. Don't have to worry about barrel life, easy to find components and the 308 is just on the edge of comfortable shooting with an ultralight rifle. But with a 6.5, you could probably on a average shoot smaller groups from any particular factory rifle. Something to be said for that. I guess that was sort of where my thought was going. Give me a 308 that has some subtle but significant design improvements that keep all the good stuff (barrel life, recoil, in my case muzzle velocity on light bullets, larger frontal area ) but impove overall precision. The .270 is interesting. Has just about the same muzzle velocity for a 130 ttsx as a 308 and a little larger than the 6.5

the "modern refinements" are really focused almost 100% on long range performance. If you are shooting under 400 yards with anything short of souped-up benchrest equipment, you wont really see the improvements nearly as much with lead bullets, and you will think its all bun and no burger. However, 400 yards IS long range for a copper mono, so since it sounds like you are shooting monos you might benefit from a bit of the new school. The old-school flat-shooting cartridges such as .270win designed for maximizing point-blank range (ie before dialing scopes were really a thing) may actually perform better for you with copper monos, ie a 270 shooting a 130 mono has a higher BC than a .308 shooting "the same" 130 mono, so even if they have the same muzzle velocity (?? I'd be surprised if they did given the difference in powder capacity) your maximum terminal range is going to be longer with the 270, and may even be longer with the 6.5cm even if its starting slower, simply due to the higher BC of the same weight bullet. Even within the same cartridge there's a difference, ie in my 270 a 129 lrx retains velocity farther than a 130 TTSX. I would be extremely surprised if you can get a factory-loaded 130gr copper mono fired from a .308win to retain sufficient velocity at 400 yards to be truly reliable, but that's easy with a 270, just for instance. Personally I woundnt worry about it being "larger", in my limited experience that's not noticeable in how effectively they kill; it's the impact velocity that warrants worrying about.

How much are you shooting that you are worried about barrel life? If you shoot that much, is getting a new barrel every so often that much of a additional burden?

 

[TaperPin]

Solid points. I didn't realize some of the prc offerings had those issues, but it makes sense. I've sort of been tempted to take a metal lathe and gunsmith class so maybe I can make a wildcat some years from now when I have more experience.

I get a big kick out of having an uncommon cartridge, even if I didn’t dream it up.

Even if you never take any hands on classes, gunsmith machining is fun to watch. Everyone does it slightly different and eventually just by watching you’ll pick out these things. The guy at Accurate Arms and Restorations has a solid process for replacing barrels and builds some accurate rifles - seems like he was a Gordy Gritters student. Other old school gunsmiths with old traditional techniques are fine for less demanding jobs, so they aren’t wrong, there’s just lower expectations. It’s just another aspect of shooting sports that’s not only interesting, but useful to help a guy make decisions about any gun work.

 

[Marbles]

I am always torn between moving to straighter walls and sharper shoulder angles (AI or Creedmoor) for better brass handling with reloading or staying with more tapered cases for smoother feeding and more reliable extraction.

At the moment I'm leaning towards sticking with older designs just to buck the trend.

 

[Colorado Cowboy]

Sometimes all that vis needed to modernize an "old" cartridge is a new powder. I always like the .220 Swift, but they have a reputation of being a barrel burner. I friend of my Dad's bought a new Model 70 Winchester in the early 1950's in .220 Swift and the barrel didn't last 1,000 rounds.

I built a new custom .220 AI Swift a few years ago and started testing different powders. We have some great slower burning powders that really make "overbore" cartridges come alive. I load my AI Swift to around 4,000 fps and great unbelievable accuracy. I have shot around 3,000 rounds thru it and the barrel shows no wear at all. The barrel is a Shilen match , stainless steel.

 

[Trumpkin The Dwarf]

I'm a stick in the mud on this topic... I totally believe the .223 is enough for elk with the right bullet, and the other hotrods let you shoot insane distances, but I've shot mule deer at 400 yards with a 30 year old 3x9 Burris scope on top of a 1939 M70 in 30-06(AI). If you "need" to shoot more than 4-500 yards, get a bow and learn to hunt for a few years. You'll find yourself getting plenty of shorter shots when you grab the rifle again.

 

[Bidwell]

the "modern refinements" are really focused almost 100% on long range performance. If you are shooting under 400 yards with anything short of souped-up benchrest equipment, you wont really see the improvements nearly as much with lead bullets, and you will think its all bun and no burger. However, 400 yards IS long range for a copper mono, so since it sounds like you are shooting monos you might benefit from a bit of the new school. The old-school flat-shooting cartridges such as .270win designed for maximizing point-blank range (ie before dialing scopes were really a thing) may actually perform better for you with copper monos, ie a 270 shooting a 130 mono has a higher BC than a .308 shooting "the same" 130 mono, so even if they have the same muzzle velocity (?? I'd be surprised if they did given the difference in powder capacity) your maximum terminal range is going to be longer with the 270, and may even be longer with the 6.5cm even if its starting slower, simply due to the higher BC of the same weight bullet. Even within the same cartridge there's a difference, ie in my 270 a 129 lrx retains velocity farther than a 130 TTSX. I would be extremely surprised if you can get a factory-loaded 130gr copper mono fired from a .308win to retain sufficient velocity at 400 yards to be truly reliable, but that's easy with a 270, just for instance. Personally I woundnt worry about it being "larger", in my limited experience that's not noticeable in how effectively they kill; it's the impact velocity that warrants worrying about.

How much are you shooting that you are worried about barrel life? If you shoot that much, is getting a new barrel every so often that much of a additional burden?

Good stuff to think about here. Im not necessarily looking for a new rifle right now but it's always fun to think about whats next on the horizon. I ended up getting a howa superlite and those only come in 308, 6.5, 7mm08 and 243. The 270 is a really compelling option, and you're right it would work great with monos, particularly out to 400+ yards. I actually wish I had that option with the superlite! 400 yards is my hard theoretical limit with the 308. And I bet I never take a shot at any deer at 400. 75-250 yards will be 99% of shots. That said, there are some monos now (that I haven't tried, other than tac-tx) that expand at 1400fps. So that does open things up a bit. I even tried a few reduced loads with h4895 and that's been fun. Nice to be able to see impacts.

I guess I shoot about 80 rounds a month right now cause I really like to practice different positions and off the tripod. So it does weigh on me to think that with one of calibers that last 1.5k rounds that I'll start loosing some accuracy in about a year. But, honestly I don't run high pressure loads so maybe I could double that. I'm still pretty new to shooting and don't have much experience with other calibers. This is just stuff I've read.

 

[Bidwell]

Sometimes all that vis needed to modernize an "old" cartridge is a new powder. I always like the .220 Swift, but they have a reputation of being a barrel burner. I friend of my Dad's bought a new Model 70 Winchester in the early 1950's in .220 Swift and the barrel didn't last 1,000 rounds.

I built a new custom .220 AI Swift a few years ago and started testing different powders. We have some great slower burning powders that really make "overbore" cartridges come alive. I load my AI Swift to around 4,000 fps and great unbelievable accuracy. I have shot around 3,000 rounds thru it and the barrel shows no wear at all. The barrel is a Shilen match , stainless steel. View attachment 859687View attachment 859688

That's pretty cool. Nice looking setup there, 4000fps is screaming. What's your favorite powder?

 

[Colorado Cowboy]

That's pretty cool. Nice looking setup there, 4000fps is screaming. What's your favorite powder?

Depends on the caliber. RE-25 for my .300 Wby with a 180 gr Nosler Partition; IMR 4350 for my .300 Wby with 150gr Sierra BT; 4895 in my .30-06 with a 150gr Sierra BT; 4831 SC in my 25-06 with .117gr Sierra BT.

My sporterized 03 Springfield really likes one powder for my hunting loads. It still has the ,military barrel and was made in 1927. It really shoots great groups with military surplus 4895. Many, many years ago my Dad and a couple of his buddies bought 40# of surplus 4895 and I worked up a load with 150gr Sierra BT bullets that shot less than moa groups at 3100 fps. Afer 20 years or so, I ran out of the powder and tried all the variations of 4895 and it just didn't shoot as good of groups. My Dad passed away about 10 years ago and I was cleaning out his reloading stuff and I found 5# of the surplus 4895 powder. Loaded some of it for my 06 and my Springfield loved these loads again.

When I get a new rifle, I start working with different powders to find what shoots best in it. The worst time I've had was getting a load for my .300 Wby. The old Weatherbys have a lot of freebore. My new Ruger #1 doesn't have it and it took quite a bit longer to get a load that I was satisfied with.