.40S&W or 9mm necked to .25?

[axxxel]

I daydreamed about PDWs today and tried to come up with something on the issue of finding a pistol/"pdw" caliber that does whatever the 5.7mm and 4.6mm does while not completely discarding "traditional" schools of thought on performance i.e. kinetic energy and bullet mass.

It struck me that something along the .30 Luger or .357 sig necked to .25 (as in .25 ACP) would probably be able to propel a 50 - 60 grain bullet at roughly the same speed as the 4.6 gets its 31 gr bullet.

The wiki page for .357 sig quotes a "special applications ammunition" load with a 60gr bullet doing just over 2400 feet. With a smaller caliber this could be achieved with a higher BC. Considering the " target speed" of the projectile is a couple hundred fps lower than 2400 you could maybe base this wildcat on the 9mm.

This conversion would be rather cost-effective and if the people buying the guns are convinced that the 5.7 and 4.6 can do the job then wouldn't a 9mm/.40-based cartridge doing the same thing with almost twice the bullet weight be a good deal?

What do you think, crazy talk? Imagine a keltec sub 2k in this cartridge; lower recoil than 9mm, with a really impressive mv.

 

[pikid89]

I feel like the pdw type guns and their respective ammo types (small light and fast) never really caught on (or will catch on) with the civilian sector...these guns were created with pretty much one main goal, to defeat body armor at a decent range from a light compact weapon. Thats an answer with out a question outside of the military world.

im not against people owning them, to each his own, but they just dont have a whole lot of utility

 

[NOLAEMT]

Isn't that what the .223 already does?

It is always good to try and think of new things, but sometimes someone beat you to it.

 

[Larry Ashcraft]

but sometimes someone beat you to it

Exactly. Look up ".256 Winchester Magnum" (.357 case necked down to .257).

Back in the 80s, one of the shooters in our IHMSA club decided the 256 Win Mag would be the perfect round for handgun silhouette. Low recoil, excellent accuracy and available in a Contender barrel.

Problem was, it wouldn't knock the targets down...

 

[x_wrench]

it might be a neat project just to do it. but for me, i dont want a bullet traveling 2400fps going through a person, and into a bystander, or through a wall in my house and get one of the kids! i will take 850fps w/ 230 g of jhp, thank you.

 

[19-3Ben]

Isn't that what the .223 already does?

It is always good to try and think of new things, but sometimes someone beat you to it.

I'm not an expert by any means, but it seems to me that .223 out of really short barrels (~10"ish) seem to lose a whole lot of velocity and get to be very very noisy. It's always the pay off when you take a rifle cartridge and stuff into a gun with a short barrel.

So what if you had something like a .40 S&W necked down to a .30cal bullet that was designed with propellants optimized for the 8"-12" bbls found on PDWs? That way you could really make the most of a cartridge.
Light recoil, light weight ammo, smaller in size than rifle rounds, and no huge pressure wave at the end of the barrel. It certainly makes sense to me. I'd go for it.

 

[rbernie]

PDW chambering are designed to be small/weak for a simple reason; to be controllable under full-auto fire at short ranges. Absent that, they offer little that other rounds cannot also provide.

 

[Deus Machina]

That's essentially what the .224 BOZ is. 9mm--originally 10mm--necked down to .223, to give the ability to fire a higher-penetrating round at the lower end of 5.56 speed, from small and existing weapons.

Theoretically, it should only require a barrel and spring swap to any existing 9mm out there.

 

[cluttonfred]

Wouldn't the 7.62 x 25 Tokarev with light bullets, hollow- or soft-point bullets be a good compromise here? Pistol platform for compact packaging, proven performance.... Something like the Brügger & Thomet MP9 (ex-Steyr TMP) in that caliber would be flatter shooting with greater range than a 9mm, not to mention the cheap ball ammo for training.

 

[isc]

I could see the advantages of a pistol cartridge necked down to take a 62-80 gr AP 5.56 bullet, but .25? not interested.

 

[Clark]

If it is penetration you want, consider a sabot.
The larger piston area is much more efficient in a short pistol barrel length.