Long term, the whole steelcase thing might be the wave of the future. We're probably just in very-early-adoption stages where there are a ton of competing ideas... in 5years i bet 90% of the variants that are now being played w are gone, and -maybe- the industry has settled into one or two designs that seem to work well enough to make do with all the issues that come up. Those 1 or 2 designs may or may not already be on the market (tho, what ends up working may need a bunch of revisions from where they currently are to be successful).
In say 5 years, if a good useful design (or two) hasnt been figured out, settled on, then it might never happen... or might be something that stays on the fringes, is only really played with by a smallish group of people looking to push the envelope for one reason or another.
TO ME, THIS ALL FEELS LIKE THE FIRST DAYS OF METALLIC CARTRIDGES. Looking back, there were so many variants... rimfire, centerfire... and the "centerfire" designs were often all over the board... look at original 45-70, they had huge (case wide) primers put INSIDE the case, and then a big crimp around outside of case to hold them in place. Or pinfire cases. Or cases with one piece for the head, the body being made of rolled sheet metal (brass, copper).
Anyways, high pressure stuff isnt maybe QUITE that innovative, but it sure is a big shake up to a system thats really not seen much change for over 120 years. I mean, early 1900s, they were shooting some rifles w about the same pressures as what you find on sporting goods stores shelves today. The performance today is better, yes, but most of that is just better powder, powder that can get to the same pressure, but hold it there longer. And powders that are much more consistent, so you dont have to build a 55k psi load (or 50k load) because on a hot day it might be 70k... or random differences in loading one cartridge to the next (such as amount of powder in it, difference in case, bullet, etc) might make one cartidge fine for pressure but the next one be way too hot)
Modern manufacturing has made pressure swings from one cartridge to the next much smaller, letting ammo companies load ammo to an average pressure much closer to the line (and really that line is about 60k to 65k in my head, tho book specs are lower for many cartridges so ammo companies load lighter for those..). But its the better powders and consistency in loading which has done most to push performance higher vs a century ago. Its not pressures themselves that have gone up really. (Talking factory loads here, handloaders been pushing things this whole time).
IF THEY CAN MAKE THIS WORK (safe 80k to 100k loads in factory rifles / cases, with cases that can be reasonably be reloaded 3 or 4 times w equipment that the average reloader can afford) IT WILL BE A GAME CHANGER, at least a moderate sized one. Will this happen? Dont know, so many hurdles. And yeah, the primers being used is a hurdle, really would like to see how thats being handled.
One thing thats made a big difference on how much pressure is being loaded by handloaders is how much better the actions are built today, esp in regards to either blue printed factory actions or custom actions. Having an action with good bearing surface on both lugs that are SQUARE TO THE BARREL CENTERLINE makes huge difference when you start shooting 70 to 80k rounds. An average older box stock action from most makers would have the bolt lifting hard, maybe needing some "extra help" be it ftom a hand smacking it, or maybe more force.
Most blueprinted factory actions / custom actions, theres not necessarily any change in how hard the bolt opens from 65k to 80k loads. Only difference is how the primer looks / how long the case lasts (esp how fast primer pocket loosens up). Cuts into margin of safety a LOT tho, because if you have one hot shell that does say 20% more then its other little friends, well if you start running 95k, then theres a point at which bad things might happen, like primer pocket opening up and venting case back at shooter - which can get dangeroys quickly for many reasons). So margin of error is much smaller w loading to these higher pressures (65k to 80k right now). One of the reasons the factories dont load to there now (before steel cased stuff). Too much risk, too much liability.
I Do find it interesting to see what these hot steel case loads will do in 30" barrels... adding 200 or 300 fps over current loads is a big deal ballistically.
Anyways, a few other random thoughts -
1. Dont suppressors have at least some recoil reducing benefits (vs a bare barrel?) By reducing the "rocket effect" of the powder gasses shooting straight out end of barrel into open air? So, a 16" canned rifle w high pressure ammo, instead of having just 15% reduction in recoil due to less powder charge weight, is that maybe a 25 or 30% reduction (or more) because of the can attached?? 25, 30% recoil reduction is pretty good amount...
2. Barrel life becomea big deal at these higher loadings. Maybe mfgs will be motivated to find better ways to getbarrels to last longer? I know that the average hunter really doesnt have to worry about barrel burnout.. but its sure a big deal in the media everyone reads. Easy for a cartridge to be labeled a "barrel burner" and have a lot of people shy away from it. And for a bunch of the people who are on this site, the extra barrel wear of 80k to 100k loads is a significant issue...
Maybe someone will figure the bugs in nitriding barrels and still keep them very accurate / otherwise problem free? Or maybe theres other new treatments / materials out there that could work. Be amazing if someone could figure out a way to have 80k to 100k loads w same barrel life as 65k today... or maybe say 50% longer life if you stay with 65k loads? Id love that if it happened. Course, theres a good chance that if someone figured that out, it would be a high end mfg where you could only get that barrel on a brand new complete rifle from them (of course, maybe in this area we're already there, maybe its just the post manufacturing nitriding of aftermarket barrels where things get iffy... at least when you are chasing 1/2 MOA or better anyways...)
I, along with many peope on here, arent interested in buying a new complete rifle everytime a barrel wears out. I think of one rifle + several barrels over its lifetime... and i still like the benefits of a custom cut chamber set up well by gunsmith, high concentricity, alignment and all that + things like throat length, tight chamber diameter for easy loading / long brass life etc... so a factory produced barrel is not super interesting to me anyways. Id just hope the tech for longer life barrels would trickke down to the aftermarket barrels i like to run
Well thats enough crazy rambling for now. This whole subject is a fascinating one to me. Opens some doors for sure, just brings as many problems, risks along with it. Will those get resolved? Be interesting to watch!
One last thing - i wonder what might happen w pencil thin stainless steel barrel in 80k to 100k load when fired at say -20 or -30 deg F? I know krieger gets concerned about that setup with 65k cartridges... add another 25% to almost 50% more stress, wonder what will happen? If super thin barrels starting popping in those conditions, then that alone might be enough extra liability for the corporate lawyers to put the brakes on the whole affair...
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