50k psi 10mm Cases

[franciscoxds@gmail.com]

I was thinking about the shell shock cases in 9mm. They have a larger case capacity than standard brass and have a pressure rating of 65k psi. A 50k psi version of this in 10mm would eclipse the 40k psi 460 Rowland. I think it possible since there are handgun cartridges' like the 9x23, 356 tsw, and 30 supper carry that have an over 50k psi rating and work fine in standard semi auto pistols. Any thoughts?

[sqlbullet]

Guns, or more specifically, chambers, for those other cartridges are designed to handle that pressure as well.  It isn't just the case head, but the entire system.  Certainly brass can handle those ratings though the 10mm case head would need to be about .020 deeper and the case walls below the brass a couple thou' thicker as well.

The bigger issue would be beefing up the action on the guns.  The higher PSI rating is going to result in faster unlock in a standard 10mm action.  Case head support will become much more critical as well.  Generally to step up the the power levels a 10mm would hit at 50K psi you are going to be looking as something gas operated like an Auto-Mag or Desert Eagle.

Consider...The vaunted 44 Magnum is a 36K PSI (piezo) cartridge (source: https://en.wikipedia.org/wiki/.44_Magnum).  Yet, AFAIK it is only offered in semi-auto handguns that are gas operated, not recoil operated.  The 460 Rowland and 10mm auto kinda define the upper limits for a recoil operated gun at about 700-750 lb-ft of energy.

It is the operation/action type that becomes the real limit.  Recoil operation isn't about the PSI as much as the muzzle energy.  9X23 and 356 TSW are 650 lb-ft energy cartridges.  The 30 SC is a 350 lb-ft energy cartridge.  These adapt easily to recoil operated guns.  But over 800 lb-ft of energy, recoil operation in a handgun of reasonable size/weight becomes a real challenge.

It is the same issue that blowback designs face.  9X18 (AKA 9mm Mak) is about as hot as you can go in a reasonable sized blowback design.  That is 23,500 PSI cartridge that makes about 275 lb-ft in typical loadings.  There are blowback designs that work for bigger cartridges.  Hi-point comes to mind.  But a Hi-Point is bulky, heavy and poorly balanced in order to support something like 40 S&W in a blowback application.

One final note of clarification:  The actual defining factor is momentum not energy.  But, bullet momentum is not usually included and energy is derived from the same inputs, so within reason it can be used in high level discussion.  However, since energy is a function of the square of velocity and momentum is not, you can get some interesting results as bullets get lighter.  For instance, 9X18 easily accommodates a 347 lb-ft load using a 45 grain bullet loaded to 1850 fps.  But, that load has less momentum (by 24%) than a 279 lbs-ft load using a 95 grain bullet a 1150 fps because velocity counts exponentially in energy.

[The_Shadow]

I'm not a fan of the shell shock casings! 

[franciscoxds@gmail.com]

Thank you for the clarification. I really like schp for their performance but the biggest downside its the amount of room they take up. So in theory if i had a strong enough case could I compensate by adding the pressure to match the performance of a shorter bullet of the same grain weight?

[franciscoxds@gmail.com]

any particular reason why the shell shock cases are not good? I was thinking of buying them to do loads approaching 356 tsw pressures from a Glock with an aftermarket barrel. I could just rechamber a barrel to 356 but the brass is so hard to find. I was thinking of using a 95gr Barnes bullet with a compensated Glock as this light bullet would provide much recoil and the extra gas would feed well the compensator. Maybe get them up to 1500 fps from a 4 inch barrel. 356 pushes 115gr bullet over 1500fps from a glock 19. These light for caliber Barnes bullets like their 125gr version in 10mm penetrate a little deeper the harder they are pushed as the pedals fold back on themselves leaving you with an explosive and controllable round. But again their weakness is that the extra length creates large pressures.

[TonyRumore]

Consider...The vaunted 44 Magnum is a 36K PSI (piezo) cartridge (source: https://en.wikipedia.org/wiki/.44_Magnum).  Yet, AFAIK it is only offered in semi-auto handguns that are gas operated, not recoil operated.  The 460 Rowland and 10mm auto kinda define the upper limits for a recoil operated gun at about 700-750 lb-ft of energy.

The Mark IV LAR Grizzly is chambered in 44 Magnum.  There was also a conversion kit for the Mark V to fire 44 Magnum.

Tony

[sqlbullet]

The Mark IV LAR Grizzly is chambered in 44 Magnum.  There was also a conversion kit for the Mark V to fire 44 Magnum.

Tony

Got ya!  I was invoking Cunningham's Law cause I knew there had to be one but couldn't think of it off the top of my head! 

I would add this this, like the Hipoint JCP40, represents the extreme of engineering the design to the purpose.  Those Grizzly's have a 27 lb recoil spring and a slide you need a wheelbarrow to carry around.  Cool guns, and unlike the Hipoint, exquisitely made, but the design compromises make them of questionable use as a "handgun".