Why/how does a bayonet on a rifle reduce the accuracy ?
In: 95
It mostly has to do with something called barrel harmonics. Barrel harmonics is how the barrel of the gun vibrates and torques under the extreme force of the pressure from firing a round. All gun barrels due this when a round is fired. The effect is far too small for you to see and usually to small for you to feel, but it’s enough to change where the barrel is pointed by a tiny amount, which means it affects the direction the bullet goes when it leaves the gun, and especially over long distances and where accuracy and precision are critical, it adds up.
All things being equal, the vibrations will be the same every time the gun is fired, so the path of the bullet is not affected. You simply factor that into your sight adjustments and it’s consistent. Attaching something to the barrel however, like a bayonet, affects the barrel harmonics. Having something in contact with the barrel affects the way it naturally wants to vibrate, and causes it to vibrate in an unusual way, which means the bullet might leave the gun at different points in the vibration cycle where the barrel is pointed in slightly different directions. This means that the bullets will be going in slightly different directions, and instead of all hitting very close to the same spot, they’ll spread out a bit.
As a bullet is fired and travels down the barrel it accelerates until it leaves the end of the muzzle. During this time the firearm is also recoiling including the barrel itself. An attached bayonet is likely to change the way the barrel recoils and resonates during this movement and can alter where the bullet ends up going. A rifle sighted in without a bayonet attached can then tend to hit in a different location once it is attached, reducing accuracy.
This same kind of issue is why very accurate rifles such as used by snipers can tend to have “free-floating barrels” where contact with the barrel is minimized as much as possible. A conventional rifle might have a forward grip that contacts the barrel and anything that warps that grip (moisture, temperature change, etc) can influence the barrel and the resulting accuracy.
As a bullet is fired and travels down the barrel it accelerates until it leaves the end of the muzzle. During this time the firearm is also recoiling including the barrel itself. An attached bayonet is likely to change the way the barrel recoils and resonates during this movement and can alter where the bullet ends up going. A rifle sighted in without a bayonet attached can then tend to hit in a different location once it is attached, reducing accuracy.
This same kind of issue is why very accurate rifles such as used by snipers can tend to have “free-floating barrels” where contact with the barrel is minimized as much as possible. A conventional rifle might have a forward grip that contacts the barrel and anything that warps that grip (moisture, temperature change, etc) can influence the barrel and the resulting accuracy.
It mostly has to do with something called barrel harmonics. Barrel harmonics is how the barrel of the gun vibrates and torques under the extreme force of the pressure from firing a round. All gun barrels due this when a round is fired. The effect is far too small for you to see and usually to small for you to feel, but it’s enough to change where the barrel is pointed by a tiny amount, which means it affects the direction the bullet goes when it leaves the gun, and especially over long distances and where accuracy and precision are critical, it adds up.
All things being equal, the vibrations will be the same every time the gun is fired, so the path of the bullet is not affected. You simply factor that into your sight adjustments and it’s consistent. Attaching something to the barrel however, like a bayonet, affects the barrel harmonics. Having something in contact with the barrel affects the way it naturally wants to vibrate, and causes it to vibrate in an unusual way, which means the bullet might leave the gun at different points in the vibration cycle where the barrel is pointed in slightly different directions. This means that the bullets will be going in slightly different directions, and instead of all hitting very close to the same spot, they’ll spread out a bit.
In some cases, like the Mosin-Nagant, rifles were sighted with the bayonet attached, and having it on is said to actually improve accuracy. Aside from that, anything attached to the barrel is going to affect the harmonics and behavior of the metal (heat expansion, vibration, twist, warpage). In a traditional rifle, a lot of effort goes into floating a barrel so nothing, no grips or handguards, anything solidly contacts it. Having a big weight lugged onto the muzzle likely isn’t going to win any sniper tournaments. I’m not an expert but that’s what I’ve learned so far.
In some cases, like the Mosin-Nagant, rifles were sighted with the bayonet attached, and having it on is said to actually improve accuracy. Aside from that, anything attached to the barrel is going to affect the harmonics and behavior of the metal (heat expansion, vibration, twist, warpage). In a traditional rifle, a lot of effort goes into floating a barrel so nothing, no grips or handguards, anything solidly contacts it. Having a big weight lugged onto the muzzle likely isn’t going to win any sniper tournaments. I’m not an expert but that’s what I’ve learned so far.
You are placing a weight on the end of a barrel which means the firer has to put additional effort into holding the rifle level which lowers their firing accuracy.
You are placing a weight on the end of a barrel which means the firer has to put additional effort into holding the rifle level which lowers their firing accuracy.
It doesn’t. This is an old wives tale that people try to back-rationalize with bad physics.
Some video games incorporate a decrease in accuracy to guns using bayonets as a means to provide a detriment that offsets the benefit of not needing to switch to a knife. But the realism of this game mechanic is similar to the realism of people dying in a single hit with a knife vs being able to sponge up bullets with every part of their body except for the head.
A bayonet has an insignificant effect on the accuracy of a gun. It may have an impact on the accuracy of the gun’s sight. This effect will be insignificant unless the bayonet radically alters the gun’s weight or weight distribution. In any event, changing from not having a bayonet to having one will have a lot less of an impact on the sighting of a gun than something like changing the type of ammunition being used.
It doesn’t. This is an old wives tale that people try to back-rationalize with bad physics.
Some video games incorporate a decrease in accuracy to guns using bayonets as a means to provide a detriment that offsets the benefit of not needing to switch to a knife. But the realism of this game mechanic is similar to the realism of people dying in a single hit with a knife vs being able to sponge up bullets with every part of their body except for the head.
A bayonet has an insignificant effect on the accuracy of a gun. It may have an impact on the accuracy of the gun’s sight. This effect will be insignificant unless the bayonet radically alters the gun’s weight or weight distribution. In any event, changing from not having a bayonet to having one will have a lot less of an impact on the sighting of a gun than something like changing the type of ammunition being used.
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