Slug speeds in different weather---

[hubel458]

Does rainfall and damp weather make regular(not heatreated)
lead slugs give different velocities than when fired
in dry weather. Like over 12 percent higher it appears
in the wet rainy weather, so the guy says. These are
55 cal slugs, about 700gr, same gun and powder charge. Ed

[Bass Ackward]

Does rainfall and damp weather make regular(not heatreated)
lead slugs give different velocities than when fired
in dry weather. Like over 12 percent higher it appears
in the wet rainy weather, so the guy says. These are
55 cal slugs, about 700gr, same gun and powder charge. Ed


Ed,

Sure. It can also go the other way velocity wise, depending on the caliber, the load, the lube. I suppose that the humidity is changing the fouling either softer or harder and maybe the lubricity too. Harder bullets and slower bullets have a wider .... functional range of not reacting to fouling. All elements produce change that the results are amplified by working at extremes for the bullet hardness, or lube quality which generally occur with the hotter the load per cartridge.

That's where Carnauba seems to help in a lube. I add Carnauba to any lube that needs it. I keep a jar under my bed. :grin:

[44man]

Don't let Bass fool you! :mrgreen: That jar is a bottle of Maker's Mark. :drinks:

[floodgate]

hubel458:

Wet air is actually slightly LOWER in density than dry air (hard to believe, but the physics of it is straightforward), and offers slightly less resistance to the moving boolit. The effect is important at long range, and in artillery ranging, though I'd not expect to see much effect at our usual testing ranges. More likely - as Bass says - a fouling issue.

floodgate

[gray wolf]

I agree with floodgate
Air density and atmospheric pressure have much to do with the answer to this Question.

[hubel458]

These were chroned just past muzzle. In the 1800 t0 2100
fps range in wet weather, and 3 days later when dry
all were about 200 fps slower. I know dryer cooler air
goes along with higher barometric readings so the air is
a little more dense. That may be it, but that much lower,
I don't know. I wonder if perhaps thr moisture in the air
would have a slippery lube affect on soft lead also. Ed

[felix]

All true, Ed. Next time you cast, try it on a night when the atmosphere is in a condensing state. In other words, if there is noticible dew on the grass the next morning, you should have been doing your casting during the night, outside where the "water" will hit the mold between throws. ... felix

[looseprojectile]

Air that has water in it has less air. You would think water would have MORE resistance, but this is not the case. Right?

Need to hold over a tad on a hot day.:-?

[Ricochet]

Water vapor is lighter than air. The molecules contain two hydrogen atoms and one oxygen, atomic weights 1 and 16 respectively, so the total is a molecular weight of 18. Compare that to the N2 and O2 molecules predominating in air: N2, atomic weight 14 x 2 = 28. O2, 16 x 2 = 32. The molecules of any gas occupy about the same space, so water vapor's much lighter.

[felix]

Ah, that's too technical. Look up instead. See the clouds? ... felix

[Ricochet]

Quite right. :mrgreen: