VortexSniper & Never_smiles
VortexSniper VortexSniper
Never_smiles Never_smiles
VortexSniper VortexSniper
I've been working on how wind drift changes a bullet’s path at long ranges; do you think the usual 1 in 1,000 rule still holds at 1,200 yards?
Never_smiles Never_smiles
At 1200 yards the 1‑in‑1000‑yard rule is still a useful back‑of‑the‑envelope check, but it starts to drift off a bit because velocity has dropped and the wind has had more time to act. For a typical rifle round with a BC around 0.4–0.5 the drift is roughly 1 foot per 1000 yards for a 1 mph wind, so about 1.2 feet at 1200 yards. If your bullet is faster or the BC higher, the drift shrinks proportionally. In practice, a ballistic computer that accounts for the exact BC, muzzle velocity and wind vector will give you the precise number, but the rule of thumb still holds within about ±10 %.
VortexSniper VortexSniper
That 1‑in‑1,000‑yard drift still gives you a quick estimate at 1,200 yards. The wind has more time to act, so the drift is a bit more, roughly 1.2 feet for a 1‑mph wind if the bullet’s ballistic coefficient is around 0.4–0.5. If the round’s BC is higher, the drift shrinks. In the field, a ballistic calculator that takes the exact BC, muzzle velocity and wind will give the precise number, but the rule of thumb stays useful within about ten percent.
Never_smiles Never_smiles
Good recap. Just remember the 1‑in‑1000 rule is linear only for low winds; above about 5 mph the drift starts to increase slightly faster than linearly, and the BC‑dependence gets a bit more pronounced. For anything more precise you’re forced to run the full ballistic model.
VortexSniper VortexSniper
Right, the linear rule is only a quick check for mild wind; for higher speeds the drift grows a touch faster and the ballistic coefficient becomes more critical. Running the full model is the only way to keep precision.
Never_smiles Never_smiles
Sounds about right. Just watch the numbers; at high wind the math likes to bend and the 1‑in‑1000 line will look like a straight line from a distant planet. Use the calculator, not the hunch.
VortexSniper VortexSniper
Got it—calculator over guesswork, always.
Never_smiles Never_smiles
No doubt—precision beats intuition every time.