What's the practical limit on handgun muzzle velocity?

[suemarkp]

As mentioned before, the powder has a limit. If you change to an explosive, they have limits too. I just found an old article which has the initial velocity for bomb and grenade fragments. That velocity depended on the thickness of the metal casing (the thinner the casing, the faster the fragments went). Grenades topped out at 6000 fps and a 4000 lb bomb topped out at 10,000 fps. At the low end (thick casings), velocity was in the 2500 to 3000 fps range. So if you could make a gun that didn't completely blow up, but only a portion of it, these may be your limits.

 

[Flechette]

Thanks all for the excellent information.

So with the given metallurgy and thermodynamic data talked about, would it be possible to make a .22 Mag +p++++ to get a 40 gr bullet to say, 2500 fps out of a handgun?

I know that the.22 Mag has considerably more pressure than the .22 LR but has it reached its full potential?

A small bore should make it easier to handle higher pressure. It could make for a more powerful Kel Tec PMR-30.

 

[Flechette]

Several people mentioned a electric railgun. Evidently the US Navy got it working up to 5600 mph (8213 fps). Here is the US Navy's prototype:

I note several things. First, it is shown firing a sabot dart but also a blocky brick type projectile which is not very streamlined. It actually tumbles/oscillates a bit.

Second, despite not using any combustion there is a lot of fiery muzzle blast. This tells me that there must be considerable erosion of the rail or projectile that then combusts with the air.

 

[jmorris]

The fasted pistols I have let them go in the 3000 fps mark and have longer than "normal" barrels for pistols.

The fastest data I have come across was for a 30 cal sabot in a 50 BMG case and were over 5100 fps for a 180 grain in a 48" barrel.

I don't know how fast it would push a 35 grain .223 bullet in a .30 cal sabot, in the 50 cal sabot but it would surely not matter as accuracy would be pretty bad I imagine. If you do try it, you might want to use solids to keep the bullet from flying apart due to centrifugal force.

 

[Cannibul]

Thanks all for the excellent information.

So with the given metallurgy and thermodynamic data talked about, would it be possible to make a .22 Mag +p++++ to get a 40 gr bullet to say, 2500 fps out of a handgun?

I know that the.22 Mag has considerably more pressure than the .22 LR but has it reached its full potential?

A small bore should make it easier to handle higher pressure. It could make for a more powerful Kel Tec PMR-30.

The rim would not contain the pressure.

 

[cheygriz]

In a practical siz handgun (1911) the .22 TCM will approach 2,000 FPS.
The FN 5.7X28 is slightly slower.

These are practical weapons, not experimental or theoretical.

A T.C. Contender in .223 with 15 inch barrel will exceed this, but it's hard to CCW!

 

[RetiredUSNChief]

Well, not handguns directly, but on the principles involved, the Germans build a multi-chambered cannon to get around at least part of this problem:

https://en.wikipedia.org/wiki/V-3_cannon

As in / similar to:

The idea's been around for quite a while and I believe Jules Verne used a system like that in one of his books --can't remember which one.

I was going to post this picture of one of the cannon designs, but... ummm... well, ladies, don't click on it.

https://upload.wikimedia.org/wikipe...n-Haskell_multi-chamber_gun_1883.jpg?download

Terry, 230RN

Pic credits in Properties

You might be thinking of Verne's "From Earth to the Moon", though I don't believe he described the gun thusly.

So with the given metallurgy and thermodynamic data talked about, would it be possible to make a .22 Mag +p++++ to get a 40 gr bullet to say, 2500 fps out of a handgun?

I know that the.22 Mag has considerably more pressure than the .22 LR but has it reached its full potential?

A small bore should make it easier to handle higher pressure. It could make for a more powerful Kel Tec PMR-30.

Not likely.

If you want those kinds of velocities, you'll have to redesign the cartridge itself, for starters. Then you'd essentially have a .223.

Several people mentioned a electric railgun. Evidently the US Navy got it working up to 5600 mph (8213 fps). Here is the US Navy's prototype:

I note several things. First, it is shown firing a sabot dart but also a blocky brick type projectile which is not very streamlined. It actually tumbles/oscillates a bit.

Second, despite not using any combustion there is a lot of fiery muzzle blast. This tells me that there must be considerable erosion of the rail or projectile that then combusts with the air.

That's what happens when a hypersonic projectile hits the atmosphere at sea level atmospheric pressure.

 

[RX-79G]

The rim would not contain the pressure.

Sure it would, if the breech and bolt where built to support it.

 

[jmorris]

Several people mentioned a electric railgun. Evidently the US Navy got itworking up to 5600 mph (8213 fps). Here is the US Navy's prototype:

It would be neat to know the distance from the camera those were fired and the specs of the mount.

To be able to track and follow something from the side moving at 8213 feet per second is actually more impressive that being able to chunk something that fast.

 

[suemarkp]

Thanks all for the excellent information.

So with the given metallurgy and thermodynamic data talked about, would it be possible to make a .22 Mag +p++++ to get a 40 gr bullet to say, 2500 fps out of a handgun?

I know that the.22 Mag has considerably more pressure than the .22 LR but has it reached its full potential?

A small bore should make it easier to handle higher pressure. It could make for a more powerful Kel Tec PMR-30.

Another velocity limiter is straight wall cases -vs- bottle neck. I don't think I've seen a straight wall case that goes much over 2400 fps (from a rifle). You want velocity, then you need a bottleneck type case.

As far as strength, pressure also pushes back on the bolt face (both thrust), so you have to deal with that as well as barrel bursting pressure.

 

[Lokichoki]

With the practical size of a handgun being a limit I would expect that that in itself would be your limit even if material is made of superman's scrotum remember every action has an equal and opposite reaction. if you want to churn as much butter as you can take a look at how pistols and revolvers have been wildcatted and you will get a quick understanding of serviceable limits. One man made a massive revolver replica but at its size is it a handgun or a cannon?

 

[Lokichoki]

I found the picture. Haha! But like I was saying shoot a linebaugh or even a heavy .500s&w I feel that is as far or as close as a handgun can be serviceable with changing what the handgun category to lets say cannon! Still though if I didn't have wrists like a granny and had a lathe mill etc I would love to chase the need for speed and break the barriers in a new platform

 

[barnbwt]

Second, despite not using any combustion there is a lot of fiery muzzle blast. This tells me that there must be considerable erosion of the rail or projectile that then combusts with the air.

That's part of it, but not all. Hypersonic projectiles actually set the air on fire simply with the force of their shockwave and profile moving through the air. At high enough energy states, the molecular bonds between atoms in molecules constituting the air are broken when the super-heated/super-pressurized shockline discontinuity passes across them, or when they crash into the body of the object itself. Free electrons and charged particles can also result, so you get a cloud of true plasma surrounding the object (this is what you see in meteors/spacecraft, and why a re-entering vehicle cannot communicate; it's inside a plasma Faraday cage built of the upper atmosphere). The ablation aspects are a real problem in the dense lower atmosphere you use guns, which is why these rail-gun projectiles have to be tungsten; nothing else will survive long enough to hit the target, and even the tungsten is a bit lighter than it started.

Of course, to even get a projectile to that point it has to scrape across a barrel or rail of solid material at the same velocity, which generates a huge amount of plasma & erosion of the firing mechanism. That Navy rail-gun is a good deal slower than the prototypes (IIRC Mach 5 vs. Mach 7) simply for longevity purposes, and even then it's still not great 'barrel' life compared to powder based guns. Still a cool field of science; when stuff is moving that fast, the impact is so sudden & abrupt that the projectile converts into rarified plasma since the kinetic energy cannot dissipate into the target as heat fast enough, which then burns a hole through whatever it hits, essentially behaving like a directed-energy weapon (but way more efficient in flight than sci-fi lasers or plasma-cannons), and splattering the inside of the tank or building with molten armor plate. Apparently at Mach 7 or so, it stops mattering what your projectile is made of, as far as the target is concerned (though again, tungsten is the only thing tough enough to survive the journey there)

TCB

 

[Flechette]

That's part of it, but not all. Hypersonic projectiles actually set the air on fire simply with the force of their shockwave and profile moving through the air. At high enough energy states, the molecular bonds between atoms in molecules constituting the air are broken when the super-heated/super-pressurized shockline discontinuity passes across them, or when they crash into the body of the object itself. Free electrons and charged particles can also result, so you get a cloud of true plasma surrounding the object (this is what you see in meteors/spacecraft, and why a re-entering vehicle cannot communicate; it's inside a plasma Faraday cage built of the upper atmosphere). The ablation aspects are a real problem in the dense lower atmosphere you use guns, which is why these rail-gun projectiles have to be tungsten; nothing else will survive long enough to hit the target, and even the tungsten is a bit lighter than it started.

Of course, to even get a projectile to that point it has to scrape across a barrel or rail of solid material at the same velocity, which generates a huge amount of plasma & erosion of the firing mechanism. That Navy rail-gun is a good deal slower than the prototypes (IIRC Mach 5 vs. Mach 7) simply for longevity purposes, and even then it's still not great 'barrel' life compared to powder based guns. Still a cool field of science; when stuff is moving that fast, the impact is so sudden & abrupt that the projectile converts into rarified plasma since the kinetic energy cannot dissipate into the target as heat fast enough, which then burns a hole through whatever it hits, essentially behaving like a directed-energy weapon (but way more efficient in flight than sci-fi lasers or plasma-cannons), and splattering the inside of the tank or building with molten armor plate. Apparently at Mach 7 or so, it stops mattering what your projectile is made of, as far as the target is concerned (though again, tungsten is the only thing tough enough to survive the journey there)

TCB

Sounds like a good explanation, but it appears that the fire only appears immediately upon leaving the railgun. Once the projectile is flying along it no longer has any fire around it. What could cause that? Cooling of some sort? The fact that more air is pushed out of the railgun when leaving than the amount of air deflected around the projectile?

 

[Flechette]

eargesplitten louden boomer,

LOL!

I'll have to use that one...

 

[kBob]

Umm actually there was a design for a nuke detonation powered "rocket" ship in the early 1960s that had it been allowed would have worked.

One design had the shield of abolative material so it intentionally came apart with each "pulse" and the other positioned the individual devices at a distance from the shield that allowed the shield to remain intact.

The systems are being studied again by some as potential earth orbit to mars engines. Not for use in the atmosphere though originally designed for such. ".....who knew....lurking beneath the ice....."

-kBob

 

[Varminterror]

So with the given metallurgy and thermodynamic data talked about, would it be possible to make a .22 Mag +p++++ to get a 40 gr bullet to say, 2500 fps out of a handgun?

Doesn't need to have fantastical metallurgy or irrational pressure levels.

Pistols exist today which will do 2400+ fps, with larger bullets than a 22cal 40grn.

To avoid flame cutting, I don't load this bullet any more, but I could exceed 2400fps out of a 7.5" Redhawk with the Hornady 110grn XTP with a .357/44.

The .256 win mag also exceeded 2400fps in 8" revolvers.

Jump into bolt action or break action sealed breach specialty pistols and bottleneck cartridges and the world changes. 14-17" barrels can get up 2,700-3,000fps in many cartridges. I have a .284 14" Remington 700 pistol which will push 140 accubonds over 2700fps, an Xp100 in the original 221fb which will also top 2700. A friend has an XP100 in .300wsm which pushes 155's to 2,800fps. I have a 204 Ruger barrel for my Encore pistol, 15" will get me 3,500 fps without even pushing max loads.

So there ARE super speed handguns out there, whether you're hunting a revolver or a specialty bolt or break action.

Too many folks get caught up on the mantra, "if you need more power, go up to a bigger bullet." Suggesting if a .357mag isn't enough for you, get a .44mag... But that does nothing for your trajectory. When I want to kill deer at 250yrds with a revolver, a .44mag is no better suited than a .357mag, as the trajectory is nearly unmanageable for field shooting at 250+. But with a 180grn spire point out of a .357/44, I'm regularly banging steel past 350. The flatter trajectory is a huge advantage. Want more range out of a handgun? I pull out a 7-08 or .284win specialty pistol and can kill deer past 500yrds.

Recognize, however, the reality of shooting a handgun over 100yrds - it really MUST be supported. So at that point, it's really a positional firearm, far divergent from the handy belt guns many folks have entrenched in their mind as the definition of a "handgun." If you can get over that predisposition, you can do amazing things with short barrels.

 

[Mauser lover]

I didn't think we were looking for significantly more power. I thought we were just dealing with velocity, which necessitates less mass to deal with the recoil (as illustrated by the pretty light projectiles in your .357 and .256). Someone already mentioned longer barrels for the single shots, but also mentioned that it was hard to ccw. The power issue is really only about getting more power at range, which is what you get with a better BC and higher initial velocity.

There was a bolt action 6mm with a 12ish inch barrel sitting in the display case of a lgs a while back... It sat there for at least a couple of years. It might still be there, but it sure looked like fun to shoot!

 

[entropy]

Define handgun- An XP-100 type pistol could be made in any rifle caliber; therefore the practical answer is which ever the fastest rifle round at the moment.

A Ruger No. 1 action type pistol might wring some more action strength, adding some FPS.

A hand-held railgun-interesting. I'll mention it to a relative who's worked on it.

I'll grab my popcorn, and let the wildcatters take it from here.

 

[BobWright]

From a practical standpoint, I have driven a 180 gr. JHP out of my 7 1/2" Super Blackhawk .44 Magnum just over 1700 f.p.s. and have shot a custom .308 Win. Remington XP-100 at just over 2,000 f.ps. As I recall a Thompson Contender in .30-40 Krag and one in .338 Woodswalker may have exceeded the 2,500 f.p.s.

However, these velocities were achieved using very light bullets. The "practicality" diminishes using such light bullets as velocity falls off rapidly down range, whereas a heavier bullet, launched at lower velocity retains more of its original velocity.

The old tried and true axiom, "every load is a compromise" remains in effect.

Bob Wright

 

[dickydalton]

My T/C Contender Super Sixteen 223 is fast, but a S&W 460 XVR with 200 grain bullets is very impressive. It is supposedly the fastest "Factory Revolver" commercially sold.
It does shoot "Point Blank" out to 200 yards.

 

[Catpop]

After seeing a space movie that had a obsolete rail gun, I did a little reading. I read the maximum fps obtainable for a 30 cal projectile was 6500 fps under the gas expansion laws.
So the government, the ones with unlimited funds to throw around, where trying to develop a weapon to propel a projectile that would penetration a Russian tanks armor. Needed 10000 fps.
Last I read on it was an actual rail gun had propelled a 30 cal at arpund 18000 fps and on a larger scale, a 2 1/2 pound projectile over 9000 fps. And it would penetration the armor.
All from memory, so numbers may be off a little. Catpop

 

[lysanderxiii]

The fasted pistols I have let them go in the 3000 fps mark and have longer than "normal" barrels for pistols.

The fastest data I have come across was for a 30 cal sabot in a 50 BMG case and were over 5100 fps for a 180 grain in a 48" barrel.

I don't know how fast it would push a 35 grain .223 bullet in a .30 cal sabot, in the 50 cal sabot but it would surely not matter as accuracy would be pretty bad I imagine. If you do try it, you might want to use solids to keep the bullet from flying apart due to centrifugal force.

Barrel length will play an enormous roll in how high you can go in muzzle velocity.

The M256 120mm/L44 shooting M829A2 APFSDS-T gets its approximately 20 pound payload (penetrator and sabot) up to just over 5,500 fps.

The L55 version of that cannon can get similar weight payloads up to 5,900 fps.

The Chinese have reportedly developed a 125mm/L60 tank gun that gets up to 6560 fps.

These works at around 80,000 - 90,000 psi.

The Germans "Paris gun", a 210/L161 gun, managed to get a 234 pound, full bore projectile up to 5400 fps, imagine that shooting a saboted sub-caliber projectille . . .

 

[Zoogster]

The top PSI is generally between 60,000-80,000 PSI.

The max PSI is a combination of things, including the limits of the metal alloys they are using. They like a good margin of safety too, which is why a proof load is a good margin above the top expected regular operating limit.

Guns also suffer wear, scratches, have characters stamped into the barrel etc So what it can handle when brand new might be slightly more than what it can handle later, which is fine if it has that margin of safety designed into it.


Then you are limited by how much time the projectile spends in the barrel. The pressure must get up to but not go over the max operating pressure, this means it will be spending some time below that as it works up to that. How much acceleration the projectile can possibly get is going to be limited by the amount of acceleration provided by the pressure behind the bullet. Which is limited to something under the max pressure pressing on the rear surface area of the bullet.
The smaller the bullet diameter the smaller the surface area it can apply that pressure and consequently the less energy it can impart to the bullet. 65,000 PSI behind a .22 caliber is going to impart less power than behind a .50 caliber projectile, even if they were able to weigh the same (which due to limits with spin stabilization they cannot.) The longer the barrel and more case capacity you have the better you can tailor a burn rate that gets the most out of the projectile and holds close to max pressure for longer.

An issue you may also be completely overlooking is barrel wear. Really high velocity setups don't last very long. The gases erode the gun. You can see flame cutting from the cylinder gap on the big bore revolvers for example. While rifles at the top of the velocity envelope need new barrels about 5x sooner than standard rifles.



Another limitation you could completely overlook is that most handguns are sidearms. A sidearm as loud as something like a S&W .460 which is operating around the same pressure as rifle cartridges but having a shorter barrel is actually louder than many rifles, and will destroy your hearing without hearing protecting in a very short time. Well sidearms generally are going to be used without hearing protection.
The pressure on these guns is so high you can cut your finger off just putting it too close to the cylinder gap, so you wouldn't want to fire it from retention either.

 

[Deaf Smith]

I am sure with the right combination of refractory metals, designs (like cone bore, polygon rifling, sabots, etc.), and new propellants one could breach 10,000 fps. Just takes $ and lots of R&D.

Deaf