"Bore Line" and Perceived Recoil

This is a discussion on "Bore Line" and Perceived Recoil within the Defensive Carry Guns forums, part of the Defensive Carry Discussions category; So I'm currently stuck on figuring something out about perceived recoil, and as the title indicates, it's what's been described to me as "bore line" ...

Page 1 of 2 12 LastLast
Results 1 to 15 of 23

Thread: "Bore Line" and Perceived Recoil

  1. #1
    VIP Member Array BAC's Avatar
    Join Date
    May 2007
    Location
    Tampa, FL
    Posts
    2,292

    "Bore Line" and Perceived Recoil

    So I'm currently stuck on figuring something out about perceived recoil, and as the title indicates, it's what's been described to me as "bore line" height.

    At every course I've been to, and every range I've visited where the discussion of handguns has come up, I hear mention of "bore line". My basic understanding of what folks are saying is that the lower the bore line, the less perceived recoil you'll feel. The most cited examples of this are Glocks and 1911's. My own experience is almost entirely with Glocks; I grew up on a G17 specifically, and have always found myself to be pretty accurate shooting Glocks of all flavors.

    So here's the question: is this "low bore line means less felt recoil" BS or legitimate? Physics wise, I can see where it has merit, but the height of the bore in a Sig compared to a Glock really isn't that different, is it?

    (I mention Glock, Sig, and the 1911 specifically because the bore height appears to be the only thing non-Sig shooters knock about Sigs, and those three types of pistols are the three I'm hovering between for picking a near-future carry gun.)


    -B

  2. Remove Ads

  3. #2
    Administrator
    Array SIXTO's Avatar
    Join Date
    Oct 2006
    Location
    Ohio
    Posts
    19,630
    Each person is different in their own perceptions. Personally, I think people make these topics far more complicated than they need to be. I really dont notice recoil anymore at all in the 3 major calibers, no matter the pistol unless I'm trying to notice to compare or whatever. It isnt that tough to shoot any pistol in the common calibers, so yes, in that sense I think its toro caca.
    "Just blame Sixto"

  4. #3
    VIP Member Array Tubby45's Avatar
    Join Date
    May 2005
    Location
    Making ammo.
    Posts
    3,047
    Getting a higher grip on the gun makes the gun sit lower in the hand. This reduces muzzle flip. This is a big reason why competitors undercut the trigger guard and install a beavertail safety on their guns. It makes it sit lower in their hand. Go to the Guns and Ammo website and watch the videos by Robbie Letham(sp?). The guy is a cyborg.

    Take a pen and hold it in your hand in line with your index finger (like you are gripping a handgun). Now wack at it backwards with your other hand. Just about flew out didn't it?


    Now push the pen down farther in your grip about halfway. Take a wack at it like before. Harder to move backwards, eh?


    Now go about half the rest of the difference left. Try another wack. Even harder yet?

  5. #4
    VIP Member Array BAC's Avatar
    Join Date
    May 2007
    Location
    Tampa, FL
    Posts
    2,292
    I see your point Tubby, and that's consistent with the physics of the idea, but I couldn't honestly tell when shooting casually the difference between the .40 and .45 subcompact Glocks when I shot them, where physics would also dictate they would feel differently.

    How well does the pen example translate to a firearm, though, all other things being equal? As I pointed out, while there is a difference in relative bore height between Glocks and comparable-sized Sig's, it isn't really very much of a difference, so I'm wondering if it's enough to produce a difference in felt recoil.

    I find it hard to argue against "higher bore line" guns like Sigs considering what professionals use them, and I'm certainly not buying a gun for competition purposes.


    -B

  6. #5
    Distinguished Member Array Chooie's Avatar
    Join Date
    Oct 2006
    Location
    Virginia
    Posts
    1,870
    It's legitimate physics. I won't go into it (it would break my brain to try to remember all of it), but if you feel saucy and want to read up on it, check this out.

    http://en.wikipedia.org/wiki/Moment_of_inertia

    In layman's terms, the muzzle rise of a given firearm is due to the force exerted by the reciprocating mass about the center of mass of the firearm. As the center of mass is brought inline with the direction of the applied force, the recoil changes as well, from a rising motion to a rearward motion.

  7. #6
    Lead Moderator
    Array rocky's Avatar
    Join Date
    Jan 2005
    Location
    MI
    Posts
    15,820
    I personally don't notice much difference in Glocks to any other brand on gun. XD's, HK's, 1911's ect all seem to be about the same in recoil.
    "In matters of style, swim with the current; in matters of principle, stand like a rock." Thomas Jefferson


    Nemo Me Impune Lacesset

  8. #7
    VIP Member Array Tubby45's Avatar
    Join Date
    May 2005
    Location
    Making ammo.
    Posts
    3,047
    Quote Originally Posted by BAC View Post
    I see your point Tubby, and that's consistent with the physics of the idea, but I couldn't honestly tell when shooting casually the difference between the .40 and .45 subcompact Glocks when I shot them, where physics would also dictate they would feel differently.

    How well does the pen example translate to a firearm, though, all other things being equal? As I pointed out, while there is a difference in relative bore height between Glocks and comparable-sized Sig's, it isn't really very much of a difference, so I'm wondering if it's enough to produce a difference in felt recoil.

    I find it hard to argue against "higher bore line" guns like Sigs considering what professionals use them, and I'm certainly not buying a gun for competition purposes.


    -B
    That was my illustration of the principle. I do not have the scientific knowlege to explain it.

    Some say it makes a difference, some say there isn't any measureable. I shoot Glocks and 1911s, both of which have low bore axis, so I have no experience with the high bore axis guns other than the Ruger GP100 revolver. That has a very high bore axis, even though it is apples to oranges, the felt recoil and ballistics are a twin of the full power 10mm. The GP100 will flip more with full power .357 Mag than my 1911 will with full power 10mm.

  9. #8
    VIP Member Array Tubby45's Avatar
    Join Date
    May 2005
    Location
    Making ammo.
    Posts
    3,047
    Quote Originally Posted by rocky View Post
    I personally don't notice much difference in Glocks to any other brand on gun. XD's, HK's, 1911's ect all seem to be about the same in recoil.
    They sit pretty low in the hand.

    I've heard this claim a lot. Usually about the SIG bashers. I've never shot a SIG so I can't comment on the recoil characteristics of their fine weaponry. (Itching for a 220SAO).

  10. #9
    Senior Member Array the_fallguy's Avatar
    Join Date
    Aug 2007
    Location
    Southern Missouri
    Posts
    544
    I don't know about less perceived recoil, but it seems to have faster shot to shot times. The recoil argument makes sense when you picture the amount of displacement allowed as the height of the barrel increases. Kind of like having more torque with a longer lever arm.
    _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
    Where self preservation is concerned, if you're not cheating, your not trying...

  11. #10
    VIP Member Array pogo2's Avatar
    Join Date
    May 2006
    Location
    Southwest
    Posts
    3,149

    2 things - recoil force and muzzle flip

    I think you have to separately define the concepts "recoil" and "muzzle flip" to talk about this subject. I think of recoil as the force backwards along the bore axis of the gun due to the pressure in the firing chamber. Because the cartridge case containing the pressure is in contact with the breech block of the gun, a backwards force is exerted, equal to chamber pressure times the area of the round base of the cartridge case. The force varies over time because the chamber pressure varies over time (as the bullet is traveling down the barrel).

    I would define muzzle flip as the rotational torque exerted by the recoil force because the muzzle of a handgun normally sits higher than the center of mass of the gun, and also higher than the "hinge point" of the human wrist. The muzzle flip causes the gun barrel to rotate upwards somewhat with each shot, until the shooter and gravity bring the barrel back down on target for the next shot.

    I don't believe that recoil force is affected by the bore axis of the gun relative to the shooter's hand or the gun's center of mass, because it depends on chamber pressure and cartridge diameter. But the muzzle flip does depend on hand position and gun geometry, as well as the strength or size of the shooter's hand and arm.

    In "free pistol" competition, there have been some .22 target guns developed that try to minimize muzzle flip by positioning the shooter's hand very high relative to the gun's barrel. The Hammerli free pistol below shows this:

    Firearms are second only to the Constitution in importance; they are the Peoples' Liberty's Teeth." - George Washington

  12. #11
    Senior Member Array dgg9's Avatar
    Join Date
    Oct 2007
    Location
    philadelphia
    Posts
    513
    Quote Originally Posted by BAC View Post
    As I pointed out, while there is a difference in relative bore height between Glocks and comparable-sized Sig's, it isn't really very much of a difference, so I'm wondering if it's enough to produce a difference in felt recoil.
    The reason, of course, is that bore axis is not the only difference between Sigs and Glocks. There's: weight, grip ergonomics, gun construction. All these are factors, so you really can't determine the effect of bore axis in isolation.

    Keep in mind: since the Sig is heavier than the Glock AND you can't tell the difference in recoil, that tells me that the bore axis advantage is cancelling out the less-weight disadvantage.

  13. #12
    Senior Moderator
    Array Tangle's Avatar
    Join Date
    Dec 2004
    Location
    Chattanooga
    Posts
    9,660
    I think perceived recoil is just that - how we perceive or sense it. But perception does not modify or change reality. Reality is, we have to deal with recoil whether we perceive it or not.

    Although from years of personal experience shooting Glocks, Sigs, and 1911s, and more lately S&W M&Ps, my position is that perceived recoil is different with some guns. First I don't know how the 1911 gets the "low bore" category. Here are some measurements - measurements were made from the firing pin or striker to a similar point on the 'beavertail' of each gun. Obviously this results in a non-precise measurement because the point that is critical on the beavertail is ill-defined, so I tried to estimate the same point on each gun. But the differences will probably be surprising.

    1911................1-3/8"
    Sig 226.............1-3/8"
    Beretta 92FS....1-3/8"
    Glock...............13/16"; the M&P would be very close to the same.
    XD....................1"

    Notice the 1911, Sig, and Beretta have essentially the same bore height, and to my surprise the XD has a relatively low bore height, and no surprise, the Glock and M&P are significantly lower than the other guns listed.

    I can't tell you how many times I've read that a 1911 has a low bore height.

    The differences are significant enough to produce significant variations in recoil. But there are other considerations as well, like the weight, and weight distribution of the gun, and in fact, how much ammo is in the gun.

    It is possible that a gun with a higher bore on a steel frame (e.g. a 1911) may not produce any more muzzle lift than a gun with a lower bore on a polymer frame. Why? Like someone has already mentioned - inertia. The heavier weight of the frame resist motion in any and all directions, including lift and rearward thrust.

    But, all things being equal, and they rarely are, a gun with a higher bore will produce more muzzle lift than a gun with a lower bore. Likewise, a gun with a lower muzzle will produce more rearward thrust than a gun with a higher bore.

    When I shoot a Glock and Sig side-by-side, and I pay attention to recoil, the Glock's recoil seems sharper and the Sig's recoil seems to lift or roll more.

    So which is better? I don't think it matters in the least. All recoil has to be absorbed, regardless if it's mostly straight back or more muzzle lift. I can not tell any advantage either way. The gun alignment is disturbed either way, and using my timer, I cannot see significant differences in recoil recovery. In fact, I seem to be able to shoot faster with a Sig DA/SA than with a Glock, which suggests that the trigger travel time and trigger characteristics, i.e. pull weight, travel distance, over travel, and reset travel may have as much to do with fire rate as recoil recovery.

    If you are using proper techniques in grip etc., I doubt you'll be able to measure a lot of difference in the effects of bore height, or that you'll be able to isolate problems to bore height alone. After all, 1911s dominate bull's eye competition and they have one of the highest bore heights of any gun.

    Ahhhh, dgg9, we were posting at the same time. After I posted, I read your post and see that we said just about the same thing.
    I'm too young to be this old!
    Getting old isn't good for you!

  14. #13
    Senior Member Array Sarge45's Avatar
    Join Date
    May 2007
    Location
    Kansas
    Posts
    962
    That's one reason instructors will tell you to get as high a grip as possible on your gun, so as to get that bore line down. There are other reasons too but it does help absorb recoil and keep the muzzle down.

    For an exagerrated example, grip your gun low on the grip and fire it. Then get a high grip and fire it. You will feel the definite difference in muzzle flip. A high bore line isn't always noticable but can affect recovery times to a small degree.

  15. #14
    Distinguished Member Array P7fanatic's Avatar
    Join Date
    Jun 2007
    Location
    Texan in NWFlorida
    Posts
    1,588

    Cool

    [QUOTE=Tubby45;565270]Getting a higher grip on the gun makes the gun sit lower in the hand. This reduces muzzle flip. This is a big reason why competitors undercut the trigger guard and install a beavertail safety on their guns. It makes it sit lower in their hand. Go to the Guns and Ammo website and watch the videos by Robbie Letham(sp?). The guy is a cyborg.

    Take a pen and hold it in your hand in line with your index finger (like you are gripping a handgun). Now wack at it backwards with your other hand. Just about flew out didn't it?

    Now push the pen down farther in your grip about halfway. Take a wack at it like before. Harder to move backwards, eh?

    Now go about half the rest of the difference left. Try another wack. Even harder yet? [quote]


    *****************
    Gotta say I don't think this analogy addresses 'bore line' as much as it does the effects of a 'full size grip' compared to a 'sub compact size grip'.

    Below you can compare the lower and higher bore line axis between an HK P7 and a Sig 220.
    The distance from the top of the hand to the bore line is much less on the HK P7.

    HK P7


    Sig Sauer P220TT
    "The price of freedom is eternal vigilance." -Thomas Jefferson

    "Liberalism is a Mental Disorder." -Michael Savage

    GOOD Gun Control is being able to hit your target! -Myself

  16. #15
    Member Array stmcelroy's Avatar
    Join Date
    Sep 2007
    Location
    Washington State
    Posts
    249
    Beyond bore height, IMHO I think that grip angle makes a huge difference.

    For me the XD45 feels much more slide heavy than a Glock 21, which I attribute to the more severe grip angle on the Glock.

    The more vertical the grip the more pressure is put on the top of your hand near the thumb which is the most unsupported place on your hand.

    With a steeper grip angle, the recoil is coming more directly through your hand and into the arm.

Page 1 of 2 12 LastLast

Links

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Similar Threads

  1. Replies: 29
    Last Post: February 13th, 2011, 09:38 PM
  2. What is the star for "reputation points" for?? (on the bottom line of a post box)
    By cammo in forum Forum News, Feedback, Problems & Comments
    Replies: 12
    Last Post: October 8th, 2010, 12:27 PM
  3. Buffalo Bore .357 magnum "short barrel" loads?
    By 1911luver in forum Defensive Ammunition & Ballistics
    Replies: 5
    Last Post: July 7th, 2010, 05:01 PM
  4. Define "Big Bore" Rifle?
    By Joshua M. Smith in forum Defensive Rifles & Shotgun Discussion
    Replies: 10
    Last Post: October 4th, 2007, 08:34 PM

Search tags for this page

bore line

,

free pistol

,

free pistols

,

gun barrel hand

,

hammerli

,

hammerli fp

,

hammerli fp 10 free pistol

,

hammerli free pistol

,

hammerli pistols

,

low bore line

,

low borelines

,
what is bore line
Click on a term to search for related topics.