Rare, if not unique, the rotary engagement of the Beretta Px4’s barrel contributes to the gun’s soft shooting characteristics.
When you invite a friend who has zero handgun experience to the range and offer them the chance to sample one of the blasters in your battery, it’s an almost certain bet that the first words they utter, as you put the handgun in their hand, are going to be “Does it kick?”
The term “kick” is a loaded one, because it’s extremely subjective. If you want to know the actual free recoil inside the system of a handgun, all you have to do is plug in a few numbers: the weight of the handgun, the weight of the projectile and the velocity of the projectile—et voila! —there’s the hard number of your recoil energy expressed in pure mathematical terms.
The thing is, the subjective experience of recoil can be cunningly manipulated via a variety of means, especially in a semi-automatic pistol. There are also a few that can be done in revolvers, but they’re more restrictive and we’ll cover them in a later column.
That perceived recoil can be quite important, however, because a sidearm that is unpleasant to shoot at the local indoor range is one that is not going to get taken out weekly or monthly to maintain proficiency.
Obviously, the largest contributor to perceived recoil is the actual free-recoil energy of the cartridge itself. All other things being equal, a .22 LR will recoil less than a .380 ACP will recoil less than a 9 mm will recoil less than a .45 ACP, all the way up the ladder to whatever is the gnarliest cartridge you dare to stuff in a pistol.
The fact that is probably the second-largest contributor is a lot less obvious, however. Namely, how well a pistol fits the shooter’s hand is extremely important in determining the perception of recoil by the novice. Typically, a good basic-handgun instructor (or a conscientious salesperson at the gun counter) will take the time to try and match up a pistol to the shooter’s hand size, ensuring that their finger can reach the trigger while keeping the backstrap centered in the grip so that the barrel is aligned more or less directly with the forearm.
When their hand is too small, it requires a technique sometimes referred to as “h-gripping,” where the firing hand is rotated forward around the grip axis to allow the forefinger to access the trigger better, therefore the meat of the hand and arm are no longer aligned behind the backstrap.
While a number of accomplished shooters with smaller hands make this work, they’re using superior technique to bull past a mechanical disadvantage, because when the pistol is held this way, every shot causes it to try and torque away from the firer’s grasp under recoil.
Going to more mechanical means, the semi-automatic pistol mechanism with the least recoil mitigation is straight blowback. With this mechanism, at the moment of ignition the only things holding the breech closed until the projectile exits the muzzle and chamber pressures drop to a safe level for ejection are the mass of the slide and the resistance of the recoil spring. This is the reason that some straight-blowback pistols, like the all-steel versions of the .380 ACP Walther PPK/s, have a reputation for snappy recoil all out of proportion to their potency.
There are various delayed-blowback systems that moderate this somewhat because some of the recoil energy gets utilized in one way or another to overcome the mechanical disadvantage built into the delay mechanism itself.
Some, like the lever- or roller-delayed mechanisms, nearly duplicate the locked-breech mechanisms we’ll discuss in a minute, but one of the more interesting is the gas-delayed-blowback mechanism, which bleeds high-pressure gas from a port located just ahead of the chamber into a cylinder in the frame, inside which rides a piston connected to the slide. Since the amount and pressure of gas that are bled off are derived from the power level of the fired round, this system effectively regulates itself based on the potency of the ammo in use.
The locked-breech-recoil systems, of which there are several, offer designers and engineers the most leeway to tailor the perceived recoil experienced by the shooter. The reasoning behind this is easily explained, if somewhat esoteric. See, while the amount of total recoil energy in the handgun always comes down to the recoil of the cartridge versus the weight of the handgun, the perceived recoil can be tinkered with.
In the case of a locked-breech-recoil handgun, when the cartridge is fired, the slide and barrel are locked together as a unit and start to travel rearward together. At some point in their travel, the barrel encounters a mechanical obstacle that uncouples it from the slide, leaving the latter to continue rearward unimpeded.
The end result of that is that the shooter feels the recoil less as a single sharp impulse, but rather slightly spread out over the short period of time it takes the slide to cycle.
The most commonly encountered locked-breech-recoil system in handguns is the Browning-type, tilting-barrel system, which is compact and inexpensive. In this system the rear of the barrel drops down out of engagement with the slide. While it does mitigate felt recoil (and is the whole reason tiny centerfire handguns like the Ruger LCP and Smith & Wesson Bodyguard 2.0 are possible), it introduces a problem of its own. Namely, the fact that the rear of the barrel drops down out of engagement with the slide means that the front of the barrel tips upward at the same time, and this introduces a certain amount of mechanical energy into the system that translates as muzzle flip, which, of course, is a subspecies of perceived recoil all its own.
One way to counter that is to use recoil-mitigating systems on the barrel itself, such as porting or an expansion-chamber-type compensator attached at the muzzle end, which we’ve discussed in detail on these pages before. Another way would be to avoid using the tilting-breech-recoil system at all.
Probably the second-most common method of locked-breech-recoil operation in handguns is the rotating-barrel variety. Currently found in a diverse array of pistols like the Beretta Px4 Storm, Grand Power X-Calibur and KelTec PR57, rather than having the barrel drop down at the rear to disengage from the slide, the barrel will rotate in place to free locking lugs from their mortises and allow the slide to continue recoiling rearward.
While this eliminates the vertical impetus for “muzzle flip,” it does involve more complex machining and may be more prone to fouling with debris and firing residue. There’s no such thing as a free lunch, after all, especially in physics and engineering.
If you’re the sort of handgun evangelist who enjoys introducing newbies to the joys of handgunnery, it might be worth considering these factors if you want to pick up the perfect beginner’s blaster.
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