Barrel extentions-whats the deal?
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Barrel extentions-whats the deal?
Why do some rifles, such as the Anschuetz 2013 have the 2013/690 variation? One has the barrel extention, and one has the solid one peice barrel. Why have the extention if you can have a solid barrel? I see a lot of competition shooters with the extention, does it help? They are both the same price.
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Shooting Kiwi
- Posts: 321
- Joined: Fri Apr 20, 2007 3:33 am
- Location: New Zealand
Good question. I don't profess to know the answer, thus feel eminently qualified to contribute!
A shorter barrel should flex less (it's stiffer, all other things being equal). Its natural frequency should be higher and the vibrations easier to damp. Angles of deviation due to flexion and off-target linear displacements due to flexion should be less for a shorter, stiffer barrel. However, it has been suggested that the ideal barrel is massive per unit length, but not particularly stiff, so that its far end is effectively decoupled from the end where the bang happens.
The extension allows a long sight radius, even with a short barrel. Perhaps it also 'tidies up' the muzzle blast. Remember that the bullet, immediately after exiting the barrel, goes slower than the escaping propellant gasses, which exit with considerable turbulence, thus the the bullet is effectively flying backwards through turbulence. Backwards-flying bullets aren't very aerodynamic.
However, like so many things, perhaps it's all just fashion.
Why have a 'solid barrel' if you don't need one? OK, it adds mass distant from the point(s) of suspension of the rifle, and therefore will increase its moment of inertia. This should reduce accelerations due to recoil, provided that the barrel doesn't flex. A long barrel is not needed to achieve sensible muzzle velocities nor low(ish) muzzle pressures for .22 ammunition.Why have the extention if you can have a solid barrel?
A shorter barrel should flex less (it's stiffer, all other things being equal). Its natural frequency should be higher and the vibrations easier to damp. Angles of deviation due to flexion and off-target linear displacements due to flexion should be less for a shorter, stiffer barrel. However, it has been suggested that the ideal barrel is massive per unit length, but not particularly stiff, so that its far end is effectively decoupled from the end where the bang happens.
The extension allows a long sight radius, even with a short barrel. Perhaps it also 'tidies up' the muzzle blast. Remember that the bullet, immediately after exiting the barrel, goes slower than the escaping propellant gasses, which exit with considerable turbulence, thus the the bullet is effectively flying backwards through turbulence. Backwards-flying bullets aren't very aerodynamic.
However, like so many things, perhaps it's all just fashion.
My abbreviated take on things.
-Balance: The balance centerline is moved back on a short barrel gun. Some people may want a slow, swooping hold with the additional weight out at the muzzle. I personally picked up 60 points in a single season when making the change to a short barrel because the improved balance dramatically increased my comfort and hold, though it is personal preference.
-Effect of wind: Outdoor only applies here naturally, but the notion is that with a short barrel and a tube, or just a tube in general, your bullet is less affected by wind, as it's subject to flight time inside the tube.
-Exit time: Shorter barrel, given a set velocity of your round, the bullet spends less time in the barrel, and is less affected by your movement.
I pay virtually no attention to #2 or #3. I was holding my own out at Camp Perry in the wind with no tube and a long barrel, at at least at my skill level, the fractions of a second aren't going to do much for #3.
If you're going to go short barrel, do it for personal preference and/or rifle balance. If you have too much weight out at the muzzle from the get-go, it's going to be a problem. Its MUCH easier to add the weight to a gun where you want it, than to take it away from somewhere you don't.
-Balance: The balance centerline is moved back on a short barrel gun. Some people may want a slow, swooping hold with the additional weight out at the muzzle. I personally picked up 60 points in a single season when making the change to a short barrel because the improved balance dramatically increased my comfort and hold, though it is personal preference.
-Effect of wind: Outdoor only applies here naturally, but the notion is that with a short barrel and a tube, or just a tube in general, your bullet is less affected by wind, as it's subject to flight time inside the tube.
-Exit time: Shorter barrel, given a set velocity of your round, the bullet spends less time in the barrel, and is less affected by your movement.
I pay virtually no attention to #2 or #3. I was holding my own out at Camp Perry in the wind with no tube and a long barrel, at at least at my skill level, the fractions of a second aren't going to do much for #3.
If you're going to go short barrel, do it for personal preference and/or rifle balance. If you have too much weight out at the muzzle from the get-go, it's going to be a problem. Its MUCH easier to add the weight to a gun where you want it, than to take it away from somewhere you don't.
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kiwi Shooter188
- Posts: 3
- Joined: Wed Feb 06, 2008 4:19 pm
- Location: New Zealand
extensions
most people use extensions to extend the length of the sight line. extensions are better cause they are lighter tri using a full lenght barrel for standing.