Robert Farago asks: “What exactly does it mean to have a high or low bore axis? What effect does that have on shooting the gun?” Great question, Robert! Bore axis has a huge impact on how a handgun shoots, and understanding that concept will give you a better idea which firearm best fits your needs.
Every semi-automatic handgun on the market works in pretty much the same way: there’s a barrel that stays more or less fixed in position, and a slide that moves back and forth in order to eject the spent cartridge and load a fresh one into the chamber. As always there are exceptions to the rule, but 99% of what you’ll find out there operates this way. The guns are designed so that there’s enough space between the top of your shooting hand and the bottom of the slide that the slide shouldn’t interfere with your fleshy bits. Every so often a gun manufacturer will cut that margin too slim and the slide will “bite” the webbing of your hand while moving, a phenomenon known as “slide bite.”
NOTE: Bore axis is also applicable to revolvers, but the best illustration is in semi-auto handguns.
The phrase “bore axis” in this context refers to the relationship between the barrel of the handgun and the shooter’s hand — “high” bore axis means that the barrel is positioned well above the top of the hand and “low” bore axis means, strangely enough, that it’s closer. Although no actual definition exists for the difference between the two, an “I know it when I see it” approach is usually used to differentiate one from the other. The common question at this point is, if slide bite is a potential issue, then why bother making the bore axis low in the first place? The reason is simple: recoil management.
An ideal handgun would place the barrel of the gun directly in the middle of the shooter’s grip in the crook between the thumb and forefinger. This would allow the recoil from each round to be directly absorbed back into the hand. But since the slide would have nowhere to go to cycle the gun that’s a tough design to pull off. Instead, the barrel and slide are typically positioned above the grip to allow that slide to cycle unobstructed. That’s good for manufacturing, but that can be bad for perceived recoil and speed on the range. Here’s why:
A classic example of a “high bore axis” handgun is the SIG SAUER P226 (pictured above and in video here). The barrel is positioned well above the top of the shooter’s hand allowing the slide to cycle with ease, but that same position means results in more actual and felt recoil.
Just like if you were holding one end of a lever, the same weight placed one inch away feels much lighter than if you placed it one foot away. The longer the lever, the more perceived force for the same weight. In our example here, the relatively high bore of the P226 means that the recoil of a standard 9mm round feels more stout. The lever in this example is the distance between the center of the barrel and the top of the shooter’s hand.
The Arsenal Strike One may be the best example of a low bore axis handgun on the market. The entire gun is designed to keep the bore of the gun as close to the top of the shooter’s hand as possible As a result that lever effect is reduced and the perceived recoil is much lighter. Less recoil means that the gun is easier to get back on target for follow-up shots, and is much easier to handle for new shooters.
In short, the lower the bore axis of the gun the less perceived recoil is felt by the shooter. Even though you’re firing the exact same cartridge with the exact same recoil, one feels lighter because it’s exerting less leverage, snapping your hand back (and your sights off target) less. Sure, you can train to get your high bore axis firearm back on target quickly, but why make shooting harder on yourself if you don’t have to?