Bullet flight time conventions

[Ulzgoroth]

Flight time: Tactical Shooting gives a couple numbers to use. I don't love those numbers, but they're there. You really should have different numbers for some weapons, particularly (mostly UT) high-velocity weapons and low-velocity weapons like grenade launchers, but other than muzzle velocity/half muzzle velocity much past 1/2d/maybe about a third muzzle velocity near max range, I don't have much to go on. And of course for UT weapons you usually have no way to determine muzzle velocity. UT has issues.

Tactical Shooting isn't changing anything with that. Prior to it there just weren't any rules about flight time for non-guided rounds except maybe artillery.

Also, 1/2d I'm given to understand is Not Done Right in a significant number of canonical sources and I'm not sure whether that's all of them or only a subset.

Max range is a maximum range at which you can use the weapon. It usually factors in both projectile ballistics and what elevation is usable. I have no information about what book authors actually do with it in many cases, but that's what it tells us. It absolutely isn't maximum range for a shot 'parallel to the ground', that's not how projectile weapons are used in any context where maximum range is a consideration.

The rule from UT for flight time for non-guided projectiles converted to guidance is nonsensical and lazy, and I would never ever follow it as written.

Guidance maneuver limits...yes, they is a thing (even for missiles with maneuvering surfaces for that matter). But they only really factor in against highly maneuverable targets, which GURPS doesn't really model all that much. Ground vehicles and infantry generally aren't going to be able to do anything that could force a miss in that way. But of course aircraft can and spacecraft might.

Originally Posted by AlexanderHowl

In the case of projectiles, I generally assume that 1/2D range represents the velocity of a round in yards/second.

That's obviously, egregiously wrong. GURPS stat-lines using the same spot in the format for the flight speed of guided weapons and the 1/2d range for other weapons does not mean those numbers are related.