05-02-2024, 08:11 AM
Not quite that easy, which is why I use a spreadsheet for each rifle/barrel. My calcs use a corrected length for a 1-way travel down the barrel. 2560 fps is actually very close to node for 18" barrel (#6.5 in my calc), within "0.79%" - I use a range bounded by +/-1% delta from "0.0" (mathematically equal to a node MV) to find an estimated range of MVs, since this is all a working estimation. A minor factor I use is cartridge length (in this case 2.260 but it can vary slightly depending on which bullet you're using), since the bullet starts its journey a bit forward of the back end of the barrel.