Bullets and the Rain.

[NICK]

I do not shoot at distance so forgive if this is a silly question.

Do you Gents that shoot long range targets notice any difference to your accuracy when shooting in the rain?

As a stalker i know how a seemingly small obstacle can send a bullet off target so how is a bullet hitting multiple rain drops on its way to target affected ?

 

Many thanks

Nick.

[The Gun Pimp]

This is a good question. Two answers - yes, you can get a 'rain-strike' as benchresters call it.

 

I've seen this at matches - 4 inch groups at 200 yards! At the last 'worlds' in France two years ago it was absolutely teeming down - stair-rod stuff. Out of twenty-five shooters, each firing around 12 shots over a seven-minute period, only one got a rain-strike - and he was one of the top American shooters!

 

More common is the drop of rain in the muzzle - this will produce a similar result - a muzzle-brake (or mod.) stops it happening

[Shuggy]

As I understand it, wet ammunition or water in the chamber can effect breech pressure. Apparently the water acts as a lubricant, preventing the brass from gripping the chamber fully and increasing thrust of the case head on the bolt. Apparently an oily chamber can have the same effect. A few years ago the NRA issued a safety warning about the potentially dangerous effects of using wet ammunition in 7.62 converted No4 actions.

 

Whether this could effect stronger actions and change their accuracy is open to question. Even so, when it's raining, I still use my Shammy leather to cover the breech and always keep my ammunition dry!

[Dark Star]

There's no question water on a round/in the chamber will affect any action, although it will depend how tight the chamber is.

 

My understanding was always that any water (even just one small drop) getting between the brass and the chamber will prevent the case from expanding to the dimension of the chamber. The knock-on effect could be increased pressure, a blown primer, change in muzzle velocity or change in POI on the target.

 

I've seen the effects during one very wet day at Bisley when I tried my best to keep the rounds and chamber dry but found that a tiny amount of water made a big difference on the target even at 300 yds.

 

I've often wondered about the effect of rain downrange and how it might alter the path of a bullet, particularly at long ranges. Sometimes on Stickledown you can be on the 1000yd firing point and see a rain shower between you and the target but I can't say I've ever been able to conclusively prove that the rain made a difference to the POI.

 

I do have a really old video which shows a variety of handgun and rifle calibres being shot through a number of different materials such as glass, twigs etc. and it is quite surprising how much deflection you'll get when even a heavy, high velocity bullet hits something on the way to the target.

 

I would have thought the chance of a rifle bullet hitting several rain drops on its way down a 1000yd range must be pretty high, so I wonder why we don't see conclusive 'rain-strikes' more often?

[Laurie]

Look at any of the specialised ultra-high speed photographs of supersonic objects (aircraft as well as projectiles) in flight and you'll see why. A shock-wave forms well ahead of the nose / tip and and pushes the air aside in a cone shape radius. It's presumably powerful enough to deflect raindrops falling through the air, but not heavier items such as twigs and branches. There must come a point when the rain is heavy enough, or it's in the form of large hailstones where it'll affect a rifle bullet, but not say an artillery shell with its much greater size, mass and air displacement.

 

I imagine that we don't often see this effect in most rifle shooting done in the open as the conditions would then be so bad that shooting will be suspended, and/or the target becomes invisible. Bench rest shooting may offer a greater opportunity as Vince points out as the competitor and rifle are under cover and protected from the worst of the elements so shooting continues as long as the target remains visible.

[Dark Star]

Good point... It almost makes me want to shoot in a hailstorm on Stickledown just to find out what happens....

 

Or maybe not

[gbal]

Vince's observation that only one in 25 shooters had a 'rain strike' is curious-very similar rain conditions,and presumably bullets and velocities-would we not expect rather more than 1 in 25?

And if it is possible-seems very implausible-to shoot through such rain,you might expect the top Americans to be able to do so!!

Gbal

[Chris-NZ]

Apparently in the old "three naught three" days in NZ, there were two schools of thought amongst the target shooters. Either try to keep your ammo dry or others preferred if it got bad enough, to lay them all out and have them equally wet.

 

The bigger variable in all this is often the effect of having water run into your bedding. That can DEF play havoc with some guns.

[Brillo]

Apparently in the old "three naught three" days in NZ, there were two schools of thought amongst the target shooters. Either try to keep your ammo dry or others preferred if it got bad enough, to lay them all out and have them equally wet.

 

The bigger variable in all this is often the effect of having water run into your bedding. That can DEF play havoc with some guns.

I've never shot from a wet bed. It must be very soggy.

[The Gun Pimp]

Vince's observation that only one in 25 shooters had a 'rain strike' is curious-very similar rain conditions,and presumably bullets and velocities-would we not expect rather more than 1 in 25?

And if it is possible-seems very implausible-to shoot through such rain,you might expect the top Americans to be able to do so!!

Gbal

Read Laurie's explanation about the shock-wave 'pushing' the raindrops away - I've shot plenty of benchrest matches in the rain but only occasionally will you see the obvious result of a 'rain-strike'.

 

Rain-strikes are probably more difficult to detect with 'shoot one, mark one' comps. but when four shots go into a half-inch and one goes out three inches - you know something happened. Normally, you would blame it on an unseen gust or lull in the wind but, on the occasion I mentioned, it was totally calm - as is often the case in very heavy summer rain.

[NICK]

Some really interesting answers Gents. I wonder how the Long Range Black Powder Shooters go on with their large Sub Sonic Bullets?

 

Thank You.

 

Nick.

[The Gun Pimp]

Some really interesting answers Gents. I wonder how the Long Range Black Powder Shooters go on with their large Sub Sonic Bullets?

 

Thank You.

 

Nick.

Again - it's one shot at a time and accuracy is so vague (no insult intended), I doubt you'd say for certain that it was a rain-strike.

[mole-e30]

Trust me rain strikes do happen........

 

Vince remember the one my Dad took in France 2" out of the group at 200 yards.....

 

they are not myths..... They make grown men cry