World’s Fastest Handgun Cartridge – or Not? The 7.5 FK BRNO

FK Brno introduced a new cartridge and pistol system a few months back, and some are calling it the fastest handgun cartridge made. But, is it really? Leaving out the handguns developed to fire traditional rifle cartridges, is the new cartridge/handgun combination the speediest on the market?

Cartridge Basics

The new FK Brno cartridge is officially called the 7.5 FK. It is a bottleneck design that is not based on any existing cartridge cases, so don’t expect to make your own with existing brass.

7.5 FK Fastest Handgun Cartridge

The 7.5 FK has a 7.8mm diameter bullet (roughly .30 caliber) with an overall cartridge length of 35mm. The case length is 27mm long.

As it was developed by FK Brno, a company located in the Czech Republic, the cartridge was standardized under Commission Internationale Permanente pour L’preuve des Armes Feu Portatives, or C.I.P. for short. This commission tests small arms and ammunition and sets certain safety standards. Although not a perfect comparison, C.I.P. is similar to the Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI) in the United States.

According to FK Brno, the design of the 7.5 FK began in 2010 when the company was approached by a customer that wanted a system to bridge the gap between existing handgun and rifle performance. Although the company does not identify this client, it appears that the cartridge was intended for military use.

7.5 FK Cartridge

Development parameters included:

  • the cartridge should be fired from a typically sized/shaped pistol,
  • using the pistol at 100 meters, the rounds should group within a 10 cm x 10 cm box, and
  • recoil should be no more than that of a .45 ACP +P cartridge.

Ultimately, the client did not pursue the design, but the company continued its development for the commercial market.

Fast…But Fastest?

In the company’s advertising, FK Brno states the new round has a muzzle velocity of 2,000 fps with a 100 grain bullet. Without reservation, that is impressive from a duty sized handgun.

But, is it really the fastest? Let’s take a look at some currently manufactured handgun ammunition.


One of the obvious cartridges to check is the 5.7x28mm developed by FN Herstal. FN developed the round to be fired from both handguns and PDWs – a mission that is similar to the original design inspiration for the 7.5 FK cartridge. Although I’ve seen 5.7×28 ammunition rated at velocities in excess of 2,000 fps, I’ve never come close to those numbers from a handgun.

For example, the SS197 SR round with the 40 grain Hornady V-MAX bullet only measures an average of 1,683 fps across my chronograph when fired from the company’s Five seveN pistol. Likewise, the American Eagle 40 grain TMJ load from Federal averages 1,638 fps across my chrony. Military loads may do better, but I’d say the 7.5 FK is likely faster.


Interestingly, the oft-maligned 9mm is capable of more than 2,000 fps from normal handguns. I’ve extensively tested the Civil Defense line of ammo from Liberty Ammunition. With a 50-grain hollowpoint bullet, I measured 5-shot average velocities in excess of 2,000 fps with a range of pistols:

  • CZ P-07 Duty: 2,015 fps
  • Glock 17, Gen4: 2,087 fps
  • Glock 19, Gen2: 2,069 fps
  • Glock 19, Gen4: 2,025 fps
  • Glock 43: 2,028 fps
  • HK VP9: 2,057 fps
  • Springfield Armory XD-S 4.0: 2,001 fps

While Liberty Ammunition might be a niche load company, I daresay the 7.5 FK is a niche caliber so I believe the comparison is fair. Of course, the 7.5 FK is very impressive as its driving a bullet that is double the weight of the one used in the Liberty Ammunition round to roughly the same speeds.

Of course, one could also argue that obsolete cartridges like the .357 Maximum and .475 Wildey Magnum could also surpass 2,000 fps by loading a lighter bullet. In fact, both of those cartridges would likely blow past the 2,000 fps threshold with a 100 grain (or heavier) bullet.

.460 S&W Magnum

This monster cartridge has loads from Hornady and Winchester that are rated at or above 2,000 fps. Smaller ammo manufacturers may have a few more. However, I am unaware of any semi-automatic pistol chambered in .460 Magnum.

.221 Fireball

If any handgun caliber deserves the “fastest” label, it might be the .221 Fireball. Developed for use in a bolt action handgun, the .221 Fireball threw lead in excess of 2,500 fps. Although the original Remington x100 is no longer made, ammo is still available from Remington, Nosler and others.

Currently manufactured loads are rated at up to 3,200 fps. I suspect that those numbers may be from a rifle length barrel, but even so, I would expect handgun length barrels to well exceed 2,000 fps.

Of course even the Fireball can’t touch the theoretical 25,000 fps claimed in a patent application from Smith & Wesson. Even assuming that was a typo (read the article), a 2,500 fps revolver cartridge is nothing to sneeze at.

So, is the new 7.5 FK the “fastest” handgun cartridge. Strictly speaking, no. However, speed is only part of the equation. I wouldn’t classify the .221 Fireball or .460 S&W Magnum as self-defense or combat cartridges in a normal context – something the 7.5 FK appears to have been designed for.

While Liberty Ammunition is able to push the 9mm beyond 2,000 fps, the 7.5 FK is designed from the ground up to do that. Who knows what limits others could push the 7.5 FK to?

What About Energy?

Bullet energy is another thing we can measure in an effort to predict the usefulness of a given cartridge. While I do not think bullet energy equals “stopping power,” I do believe energy plays a role in the terminal effectiveness of a round. Energy levels are also used by some hunters as a rule of thumb when deciding what cartridges may be suitable for what kinds of game.

7.5 FK shot in ballistic gel

A 100 grain bullet moving at 2,000 fps generates about 888 ft-lbs of energy. That is extremely impressive from a handgun. So, how does that compare the the above mentioned cartridges?

Bullet WeightVelocityEnergy
7.5 FK100 gr2,000 fps888 ft-lbs
5.7×28 (FN SS197 SR)40 gr1,683* fps252 ft-lbs
9mm (Liberty Defense)50 gr2,025* fps455 ft-lbs
.460 S&W Magnum (Hornady Custom FTX)200 gr2,200 fps2,150 ft-lbs
.221 Fireball (Nosler Custom Ballistic Tip Varmint)40 gr3,200 fps910 ft-lbs
*velocity measured by author

Compared to the 5.7×28 and 9mm loads, the 7.5 FK generates significantly more energy. If the felt recoil is that of a .45 ACP +P, then that might be a good trade off for many people.

What is also impressive about this cartridge is that at 100 meters, the bullet is still able to deliver more than 500 ft-lbs of energy.

The Guns

7.5 FK Field Pistol

Ok, so FK Brno has an interesting little cartridge, but its all for naught if there isn’t a reliable gun from which to shoot them. Enter the 7.5 FK Field pistol.

The pistol is a single action handgun that uses a tilting barrel and holds 14 rounds in the magazine. It has a 6″ barrel and weighs just under three pounds. The rear sight is designed to be easily replaced by a Trijicon RMR sight.

According to FK Brno, the new 7.5 FK Field pistol is an entirely new design with a special recoil attenuation system that has been patented by the company.

7.5 FK Recoil System

The company has not offered specific details on how the system works, but has provided the graphic above comparing a standard recoil system with their new system.

Proprietary Pricing

Right now, the 7.5 FK pistols are not being imported into the United States. However, American Rifleman reported that the company was in negotiations with a Florida-based importer to bring the guns into the country. There are several importers here in Florida, but two large ones immediately jump to mind: Century Arms and EAA Corp.

Of course, all of this is pending BATFE import approval.

most expensive pistol

The real problem for this gun and cartridge is the rumored price. According to an article in the American Rifleman, the gun “…could be well north of $5,000.” If that is so, I do not expect many of these guns to sell.

Last Update: October 17, 2022

By Richard Johnson

Richard Johnson is a gun writer, amateur historian and - most importantly - a dad. He's done a lot of silly things in his life, but quitting police work to follow his passion of writing about guns was one of the smartest things he ever did. He founded this site and continues to manage its operation.

25 replies on “World’s Fastest Handgun Cartridge – or Not? The 7.5 FK BRNO”

This is certainly interesting and something that has piqued my interest, but I’m probably not wired like the “average” firearm enthusiast. Unfortunately, proprietary firearms offered at proprietary prices will most likely hamper adoption and proliferation of ammunition from more than one manufacturer. It will be an interesting launch to watch.

I really appreciate the coverage as this was totally new information for me. I am curious why you chose the 5.7 x 28 over the faster 22 TCM. The TCM also makes 2000+ fps from a service length handgun.

Good call to include the Liberty ammo. That stuff is beastly fast even in 3 inch barrels. I got 1950 fps average from a Kahr PM40 when I tested it.

I completely forgot about the 22 TCM – I’m glad you mentioned it. I enjoyed shooting one of those at
Media Day, but haven’t been able to justify spending the money on one for my own.

In the past I have chronographed 5.7 loads, the early full powered loads, in the 2000fps range. At the same session the new stuff was in the 1600fps range. I believe it became watered down for polotical purposes… This new cahmbering is basically a 30 carbine loading, more or less, except it’s a 100gr vs a 110 grain bullet at 2000fps. Also note that Coonan has offered a 1911 type pistol in the 30 carbine chambering for quite some time.

I know that Coonan offers 1911 style pistols chambered in .357 Magnum, but I cannot find any reference to them making something in .30 Carbine. Are you thinking about the old AMT AutoMag III?

I really like the looks of the Brno but $5k would price me out.
I have chrono’d Elite Ammuntion’s T6B 5.7 28gr to over 2400fps from my 6″ barrel. Buffman got 2355 from the standard 4.8″ barrel. My own hand loads drive a 45gr to an average of 1883.

I enjoy your videos Pocket Guns and Gear:-)

i was about to mention them! I keep some elite ammo around but the back order is horrendous. Thanks ATF.

Considering the Bottle Nose, and the country of origin, and the diameter, it is clear that this is a modernized Tokarev. Just look at the trends with Lehigh Bullets and Copper Ammo. You take a longer brass or copper bullet for better sectional density, pop it into a bottle neck .30 caliber, and put it on a variant CZ frame. Vwalla. 7.5 FK is born. Tokarev was originally 7.87mm diameter, 85-90 grains, and 1600-1720fps. Also extremely popular in Czech Republic, Romania, etc. It’s identical to a Tokarev, if the Tokarev used steroids.

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