Why a high bore axis?

[Sam1911]

High bore axis or low really has very little to do with inherent accuracy, or the ability to shoot a handgun precisely. It is one of the factors that influence how quickly a (usually competitive) shooter can see the sights return to target and complete his/her next shot.

It's kind of like spoilers or ceramic brakes on a car. Most drivers will never have any need to come close to operating it to the level where those things make an appreciable difference, but they like to buy them and debate about them anyway.

For most shooters, a SIG or HK is just fine.

 

[BigG]

Looks like Linebaugh almost ate the barrel when it rared back.

 

[SDGlock23]

I prefer a low bore axis, but I don't hate guns with high ones. I like the XD/XDM series but I don't care for the high bore axis, it just seems like it makes the gun sit so high in your hand, and I don't care for that. I'm just spoiled by Glocks I think.

 

[tarosean]

Way too many other factors that trump bore axis...

 

[johnnydollar]

The HK P7 has a low bore axis.

 

[twofifty]

In rimfire, the winner of low bore axis has to be the IZH-35M. The bore is so low, the hammer swings down from the top.

I came upon your post as I was thinking that hammer length might be related to bore axis height.

An effective hammer needs enough whumph to ignite the primer. The power for this comes from a spring powered lever, i.e. the hammer & mainspring. Each are usually configured in a vertical arrangement, which eats up bore axis real estate.

edit: this business of arranging essential components in the tightest of 3-D spaces makes handgun design an interesting subject.

 

[Strahley]

This whole "bore axis" thing is just another one of those catch phrases that'll lose steam when the next one comes along. I could see it being a problem if you were trying to shoot a .500 S&W revolver with the barrel 3 feet above the grip, but arguing about fractions of an inch in common auto-loader calibers is silly

 

[twofifty]

This whole "bore axis" thing is just another one of those catch phrases that'll lose steam when the next one comes along. I could see it being a problem if you were trying to shoot a .500 S&W revolver with the barrel 3 feet above the grip, but arguing about fractions of an inch in common auto-loader calibers is silly

Seems that way.
Maybe someone here with a knowledge of physics can calculate what force change results from a 1/10" reduction in the bore to top-of-grip relationship.

The relationship above is the length of a force lever of some sort. Would a 1/10" reduction in the length of this lever result in quantifiable & noticeable reduction in barrel flip?

If this distance is 1" and the reduction 1/10", then maybe there is a benefit to a low bore axis.

 

[MarshallDodge]

At the last bowling pin match I came in 5th place out of 40 with a "high bore axis" H&K P30. Behind me were Glock, 1911, Sig, XD, and M&P pistols, and a couple revolvers. Not bragging, just saying like a few others on here have said, bore axis is not as big an issue as you may think.

Find a gun that is comfortable and get out and shoot as much as you can afford.

 

[Nom de Forum]

This whole "bore axis" thing is just another one of those catch phrases that'll lose steam when the next one comes along. I could see it being a problem if you were trying to shoot a .500 S&W revolver with the barrel 3 feet above the grip, but arguing about fractions of an inch in common auto-loader calibers is silly

If you haven't noticed the difference that small changes in the height of the bore axis makes when shooting similar pistols in the same caliber perhaps you do not have the perspicacity to do so or have just not done much comparison shooting. To determine the former perhaps comparing a Glock/M&P to a XD that you have loaded the magazines to make the weight of each pistol equal before shooting would be helpful. I think you will notice the pistols with lower bore axis make it easier to recover from muzzle flip and that is not an attribute that should be dismissed as silly.

 

[jerkface11]

I had a Steyr M40 and it was the least accurate handgun I've ever fired. I think I had a lemon though.

 

[Nom de Forum]

I came upon your post as I was thinking that hammer length might be related to bore axis height.

An effective hammer needs enough whumph to ignite the primer. The power for this comes from a spring powered lever, i.e. the hammer & mainspring. Each are usually configured in a vertical arrangement, which eats up bore axis real estate.

edit: this business of arranging essential components in the tightest of 3-D spaces makes handgun design an interesting subject.

I agree the details of design for best use of space is interesting. I have learned more about the pistols used in the Olympics in the last few days than in the previous twenty years. All very technically interesting. This information has marginal value for understanding and using SD and hunting type pistols but it does have value.

Originally Posted by tuj

In rimfire, the winner of low bore axis has to be the IZH-35M. The bore is so low, the hammer swings down from the top

tuj,

I think the single shot striker fired Free Pistols have the IZH-35M beat in the lower bore axis category and I suspect the Walther SSP striker fired semiautomatic may also have a lower bore axis. After looking at some great photos tuj posted in another thread and checking what is available online I now agree the IZH-35M has a lower bore axis than the Walther SSP.

As others have posted in various ways: having a lower bore axis pistol is not the most important factor in winning a match or surviving a gunfight, but it is certainly one of the many factors the help make doing both easier. Improving many little factors of a complex operation is often equal to making an improvement to one big factor.

 

[ricebasher302]

I generally feel like I possess more power over the handgun if it flips less during recoil. Bore axis is definitely a consideration for me, but generally only as it relates to a defensive pistol where I value sight acquisition more than I would with a range toy. While not a Glock fanboy by any means, I notice and appreciate the feel that my G17 creates with its low bore axis. But this in no way detracts from the love I have for my FNP-45

Those who've stated that the real world benefit is likely to never be experienced by most casual shooters are correct in my opinion.

 

[Mike1234567]

I can only compare the Hi-Point .45 JHP I once owned with a S&W M&P .45 I also owned. Despite the large weight difference, the S&W had far less perceived recoil. I can only guess this is due to the high bore axis on the Hi-Point but it might also have to do with HP's blow-back design too. I dunno. Same exact ammo in both pistols.

 

[hentown]

I can only guess this is due to the high bore axis on the Hi-Point but it might also have to do with HP's blow-back design too. I dunno. Same exact ammo in both pistols.

I'd hazard a guess that the blow-back design, combined with that pot metal slide would make for more muzzle flip and perceived recoil.

 

[Rexster]

I never worried about bore axis, or muzzle flip, until arthritis started affecting my right wrist in late 2011. Straight-line recoil is now much friendlier than any amount of muzzle flip. My SIG P229R .40 duty pistol now HURTS with every shot, unless I hang a Surefire Weaponlight on the rail, to dampen the recoil a bit. Even with the light mounted, the cumulative muzzle flips during a 60-round qual will result in an aching wrist for a while afterward, which is not a good sign. Thankfully, I am in the twilight of my LE career, so the number of mandated quals is, hopefully, tolerable.

Step One was to bring my Les Baer Thunder Ranch Special 1911 out of semi-retirement, to be my off-the-clock pistol. Notably, a Baer frame is relieved at the junction of the trigger guard and front strap, allowing it to ride lower in the hand than a standard 1911 frame.

Step Two was to buy a G17, in 2012, when I learned my chief was considering allowing 9mm as an alternative duty cartridge. My chief never signed-off on the proposal, but the G17 became my usual concealed-carry gun. Then, I acquired a pair of Gen4 G19 pistols, one at a time, in 2013 and 2014.

 

[barnbwt]

"Seems that way.
Maybe someone here with a knowledge of physics can calculate what force change results from a 1/10" reduction in the bore to top-of-grip relationship."

The change is directly proportional; force times distance from the pivot is torque. Double it, the twist is double. But there is also a compensating factor in that the gun's own mass and the position of that mass (the moment of inertia, to be specific) governs how much rotation an impulse will deliver and how quickly. Long barreled revolvers "roll" comfortably because the barrel mass way out there slows down the pivot motion enough that your hand and knuckles aren't torn up. A snub airweight S&W has the opposite problem.

Emilio Ghisoni (of Mateba auto-revolver and Chiappa Rhino fame) designed the majority of his pistols with extremely --even radically-- low bore axes. This is because he specialized in competitive target guns. His 38spl MTR8 pistol is reportedly ridiculously easy to make follow up shots with (low bore and the mass of the barrel and cylinder are far from the shooter's wrist)


It's the middle one . This picture comes from lifesizepotato's excellent online website devoted to Ghisoni's unappreciated genius in the firearms world.

I've heard a lot of people defending high-bore guns (*cough* SIGs *cough*) claim that the buck and roll is actually a good thing, since that motion is dissipating energy that would otherwise batter your palm. Do you punch with an angled wrist, so your first and second knuckle take the blow and the tendons on the far side of your wrist dissipate the energy by extending (straining, one might say )?

TCB

 

[1SOW]

In a std PISTOL: Bore axis is the height of the bbl ABOVE your highest grip area
Recoil FORCE is divided into TWO directions due to how the pistol is held.
1. Recoil pushes opposite the bbl - muzzle
2. Your grip is below the barrel forming a lever, so part of the force PIVOTS on your wrist and the muzzle rises.

Recoil force that is only straight back is fairly easy to manage.
Muzzle flip with the leverage formed WILL take place.

The higher your grip in relation to the muzzle, the less the recoil force affects muzzle flip.

BENEFIT: With ZERO muzzle flip (like in a perfectly tuned OPEN CLASS pistol with a muzzle break, the second shot can be taken almost instantly after the first. Sights aren't lost with just recoil and no muzzle flip.

Do a simple test: Hold your pistol 1/2" lower than you normally do and shoot. Fire the next shot when the front sight is back on target. THIS is the same as a having a HIGHER bore axis.

Now grip your pistol high/normally and shoot and then again when the front sight is back on target. THIS is similar to getting a pistol with a LOWER bore axis.
I know 1/2" is quite a bit of change, but the principle is the same.

Which would you prefer if dealing in fractions of a second?

 

[SAWBONES]

Why indeed?

The Sig-Sauer DA/SA guns, the Springfield Armory XD pistols from Croatia, various Walthers, various Berettas and any number of other semiautos have relatively high bore axes relative to the position of the shooter's hand on the stocks and trigger.

With revolvers, whether SA or DA, the bore is relatively high due to the traditional geometry of the lockwork and cylinder (excepting the new Chiappa Rhino, of course).

Obviously, many folks have "brand loyalty" or value a given maker's reputation, or recognize an element of build quality in a certain gun, which they value above ease of shooting, and accordingly will put up with a high bore-axis gun.

And of course many folks may not even recognize that there's any difference, or simply won't care.

I do, though, and given a choice in semiautomatic pistols, I'll always prefer a gun with a lower bore axis, e.g., Glock, 1911, HK P7.

 

[Skribs]

For those who say "doesn't matter, buy what you want," that's kind of outside the scope of this thread but also kind of the reason I made it. If I were designing a pistol, a low bore axis wouldn't make you less likely to buy my product. But a high bore axis would make someone else less likely to buy it.

 

[Nom de Forum]

For those who say "doesn't matter, buy what you want," that's kind of outside the scope of this thread but also kind of the reason I made it. If I were designing a pistol, a low bore axis wouldn't make you less likely to buy my product. But a high bore axis would make someone else less likely to buy it.

Yup. I suspect the future for semiautomatics is lowest possible bore axis, and striker fired or a hammer system similar to the new R51. As soon as either offers the same accuracy, trigger pull characteristics, and other desirable ergonomic characteristics as competition grade 1911s, the 1911 will slowly fade into history as the top competition pistol.

 

[Mike J]

I have 2 pistols that I consider high bore axis. My XD-40 & an old Ruger P94. I didn't see what all the fuss was about until I shot a Glock 23. The follow up shots are quicker although recoil feels more pronounced to me. I am not getting rid of the Ruger or the XD but it is something I pay more attention to regarding future purchases.

 

[mavracer]

One thing every body extoling the benefit of lower bore axis seem to ignore Newton's third law. While a higher bore axis gives the barrel more leverage to cause muzzle rise it also gives the hand more leverage to control muzzle rise.

 

[Sam1911]

But we DON'T, and SHOULDN'T be attempting to "control" muzzle rise. That idea faltered in the '90s.

 

[BigJakeJ1s]

Very interesting responses here.

We usually compare different pistols' bore axis height above the top of the gripped surface, but the major pivot point for the shooter is lower than that (and much farther back): in the pivot of the wrist.

Therefore I suspect grip angle may also play a significant role in the amount of muzzle flip compared to "straight back" recoil, since a more swept grip angle would raise the wrist pivot point in relation to the grip, placing it closer to the bore axis.

But grip angle affects "natural point-ability" too. Some people prefer the more angled grip that might help reduce muzzle flip. Others prefer (and shoot more quickly and accurately with) a less swept grip angle that "points better" for them.

Seeing the animated graphic of the Sig (I think?) made me also realize that different actions, trigger linkages, and striker vs hammer firing mechanisms also affect the geometries and height of the bore axis relative to the grip. The graphic showed the DA linkage from an upper appendage of the trigger, back to the hammer. A 1911 trigger has no pivot, and the linkage is lower (not having to cock the hammer). I'm not as familiar with striker fired internals, but depending on when/how the striker is cocked, I would guess they could require less vertical space between bore axis and grip.

Also, very low bore height above the grip can lead to slide bite for some shooters with large hands. The low bore height of the R51 has bitten at least one reviewer. Too bad I have large hands; I'm a big fan of SAO triggers.

Andy