Hi all, new to The Hide, first post. Great site!
As it relates to accuracy, does a projectile usually become unstable just at the point that it crosses through the transonic region, or does degradation in flight path usually take place at some point after going from sonic to subsonic? How do projectile parameters affect the stability of a bullet as it goes through this phase?
I am very new to shooting rifles, and have a real ineterst in long distance shooting in particular; I have been shooting a 10/22 at 50 and 100 yards to work on all my basic marksmanship skills. In the process of doing this, I discovered something sort of odd. While my particular rifle shoots well (.5 to .75 MOA very consistently) at 50 yards with subsonic ammo such as Eley or Remington Subsonic (1070 fps or so, 38gr), 100 yards with this ammo is a joke. It doesn't follow the trajectory curve at all, and is all over the place windage-wise. When I step up the ammo to a CCI MiniMag (1235 fps 40 gr), I notice that the 100 yd groups come right on into where they should be (1.5-2.0 MOA or so). What's getting my attention is that, according to my ballistics calculator, the MiniMag goes subsonic somewhere around 30-40 yds or so. If this is true, then shouldn't I be seeing a lot more variability in my groups at 100 yds than what I am? This would lead me to believe that, with this particular round (the MiniMag), that the instability is actually introduced somewhere well after the projectile goes subsonic.
Do all rounds behave this way? Is there a way to consider BC and projectile shape and make a prediction of where this instability is going to take place? Am I missing something (more than likely)?
I have a R700 in .308 that I will be stepping up to shortly, and I'm trying to figure out as much as I can now so that I can understand and apply what I'm learning with the .22LR.
Thanks for any and all input!!
As it relates to accuracy, does a projectile usually become unstable just at the point that it crosses through the transonic region, or does degradation in flight path usually take place at some point after going from sonic to subsonic? How do projectile parameters affect the stability of a bullet as it goes through this phase?
I am very new to shooting rifles, and have a real ineterst in long distance shooting in particular; I have been shooting a 10/22 at 50 and 100 yards to work on all my basic marksmanship skills. In the process of doing this, I discovered something sort of odd. While my particular rifle shoots well (.5 to .75 MOA very consistently) at 50 yards with subsonic ammo such as Eley or Remington Subsonic (1070 fps or so, 38gr), 100 yards with this ammo is a joke. It doesn't follow the trajectory curve at all, and is all over the place windage-wise. When I step up the ammo to a CCI MiniMag (1235 fps 40 gr), I notice that the 100 yd groups come right on into where they should be (1.5-2.0 MOA or so). What's getting my attention is that, according to my ballistics calculator, the MiniMag goes subsonic somewhere around 30-40 yds or so. If this is true, then shouldn't I be seeing a lot more variability in my groups at 100 yds than what I am? This would lead me to believe that, with this particular round (the MiniMag), that the instability is actually introduced somewhere well after the projectile goes subsonic.
Do all rounds behave this way? Is there a way to consider BC and projectile shape and make a prediction of where this instability is going to take place? Am I missing something (more than likely)?
I have a R700 in .308 that I will be stepping up to shortly, and I'm trying to figure out as much as I can now so that I can understand and apply what I'm learning with the .22LR.
Thanks for any and all input!!
