Wind number and caliber/cartridge

[TaperPin]

The best advice I’ve ever been given is to stop going to the practice range only when it’s nice, and try to be there for the worst conditions. I’ve known some gifted wind estimators, but I’m not one of them even though I’ve grown up in the wind, 5 min from a range and an hour from prairie dog towns. I suck.

In nice smooth even wind I’ll still be off by +/- 20%. 8 mph feels a lot like 10 to me. In gusty or hard to judge wind I’m more like +/- 40%. Without wind clues 6 mph could be 10, 12 could be 20. An easy consistent wind at a weird angle puts it in the +/- 40% category. Everyone is different and my numbers don’t matter, but it’s nice to have a rough idea what your own numbers are.

One day was extra windy even for Wyoming and our 300 yard 10” plate was pretty safe. Our wind calls had us hitting close to both sides, but rarely actually hitting the plate. Obviously too much wind for our abilities at 300, but 200 yard hits were still quite doable. Before that day I would have never shot at any animal in those conditions, but now I wouldn’t hesitate to take that 200 yard shot at a 10” target - try it and you might find 200 yards is very forgiving. Again, my numbers don’t matter, but it’s nice to know yours if a worst case scenario comes up. Only once in my life has a worst case wind situation come up while hunting and it actually made a close stalk easier than expected - they were hoping we’d put them out of their misery.

 

[Wrench]

The good news is stalking with a 20 mph wind gives you about a 270* option for stalking.

 

[TaperPin]

I corrected the size of our plates mentioned above - should have said they were 10”. That story probably makes more sense now.

 

[762 ULTRAMAGA]

Short version:
What caliber, cartridge, bullet, and velocity gets the best wind performance? How does this change when recoil is considered?

I was scouting for goats the other day in an area I have a tag for when season starts. I glassed up a Billy in a saddle, at that point in time winds were 15-20 mph running almost exactly left to right. The goat was at 600 yards, assuming I stocked to 300 yards, the conditions that day would have given me a 16 inch drift (4 mph 223 with 77 TMK at 2700 fps). The day before I had 20 mph sustained winds with gusts of 35 mph on an exposed ridge, saddles felt worse, but I did not pull the Kestrel out. This means a wind gust could have moved my shot by almost 13 inches if I was holding for a 20 mph wind.

This has me certain I will be bringing my 243 come August. However, even with 108 ELD-Ms the 243 is only a 5 mph gun (expected velocity 2900 fps), 11 inches of drift at 300 yards with a 20 mph wind, 19 inches in a 35 mph wind. This is much better. However, even if I can launch a 108 ELD-M at 3200 fps from something like a 6 UM it is still only a 6 mph gun.

Playing in AB it looks like a 7mm is were BC starts to really improve wind performance with a 180 ELD-M at 2600 fps being a hair better than a 6 mph gun (I think that is a reasonable short barreled 7mm-08 velocity?, though it might be optimistic). Same bullet gets a 7 mph gun if one steps up to something that pushes it to 2800 fps. It looks like a big 300 does not really get better wind performance, for example, a 225 ELD-M thrown at 2800 fps (300 PRC) is still a 7 mph gun and brings a lot more recoil.

I will be shooting my 243 barrel out before getting any new cartridge, however I'm questioning if I will stay with a 6mm. However, based on my ability with a suppressed 308 slinging 178 gr bullets, at present recoil is a clear issue for my shooting ability, and trading poor shooting all the time for better edge case scenarios is fullish. So not saying I will go bigger either.

Given that @B_Reynolds_AK uses a 6mm, I'm probably wasting my time (but I'm watching the kids today, so not like I could be in the field or actually shooting with the time).

Shooting in that kind of wind isn't going to be solved with a whizbang miracle cartridge.
Guys I shoot with are winning in high wind matches sending 105 bergers around 2750, they can shoot the wind because they do it almost every day.
I've killed a lot of animals at long range but high wind is a no go for me beyond 300 yards

I shot a match last month with cross canyon targets, the wind didn't register on my side but I was missing by over a mil in windage on the other. To make it worse the speed and direction changed by the second.
I quit using a kestrel for wind calls cuz it's about useless in the mountains.

If you're set on slinging led in 20mph winds at least use a 147 or 180, when you make a terrible hit the chance of killing the critter will at least go up..

 

[Marbles]

While I will still practice on shots like this, I have learned don't expect to shoot at an animal across a saddle like this.


It was warm at 75 degrees, density altitude 4500. Wind was almost exactly left to right, the arrow points to a spot 600 yards away, wind was 4 mph with 12 mph gusts on the summit. On the ground in the saddle (200 ft lower in elevation )it was gusts up to 19 mph.

My assumption, is that a bullet would be exposed predominantly to winds like I had on the summit, but with a 5 mph gun the gusts could still push the bullet off by over 0.6 mil (12 inches).

No shooting practice today to test it though, a hiking trail runs through that saddle.

 

[Marbles]

I quit using a kestrel for wind calls cuz it's about useless in the mountains.

Wind at the shooter obviously is not the same as wind along the flight path. However a Kestrel is a great tool to learn. Most people don't get into high winds enough to know what they feel like, and a 30 mph wind will be called 40 mph. Plus, you can then connect the number with how plants and other things in the environment move in that wind. Same thing with an inclinometer, mountains don't run in straight lines, but most people grossly over call inclines.

I referenced the Kestrel only to be clear that those were real wind speeds and not an uneducated guess. Uneducated because I'm only starting to pay attention to wind and I called those winds at my location as 10 to 20 mph higher than they were in reality.

 

[Dobermann]

If I could go back I’d own a 223 and a 6.5 creedmoor and stick with that. I’d build both to be ~10 pounds suppressed and be happy.

That's what I'm heading towards ... for just buying ammo / not reloading, and having good options usually available off-the-shelf and/or orderable by the carton, this combination does all I'd really need, hunting or comp-wise.

Aside from the .22LR for small critters, the 308 Tac A1 "just because", and the 338 Lap for HTI fantasy land, of course.

 

[HingleMcCringleberry]

Taking shots on animals in 30+ mph winds… don’t do it regardless of cartridge or bullet. You will eventually, and at a relatively high rate- miss call badly.

Listen to the man, he is correct. Been there learned that lol

 

[mt terry d]

We just spent 6 days shooting in really broken terrain with 17 people, and the hit rates were all based on the shooter. From 223’s to 7 PRC and lots of things in the middle. The best performer as a cartridge/bullet combo to 1,022 yards was a 22CM with 88’s. There were also people really close/right there with a 6.5 PRC with a hot 147gr load, 6cm with 108gr factory, and out to 550 yards or so multiple 223’s even with 69gr SMK’s. One shooter was also right there with the top guys with a 308win and 168gr Good Medal match to about 600 yards.

I'd like to see video evidence.

 

[solarshooter]

Cross posting this post I made in another thread. No judgement on cartridges here, just some rough numbers and my attempt to quantify the "wind number vs recoil" question.

I've put this together over the last couple weeks, kind of interesting. Percentages are all relative to my 284. The 28nos powder effect has been artificially cut down to reflect perceived recoil with a brake. Masses of rifles and load data reflect real and hypothetical builds.

mp = mass of powder
vp = velocity of powder
mb = mass of bullet
vb = velocity of bullet
mr = mass of rifle
vr = velocity of rifle
pr = momentum of rifle
er = energy of rifle
Wind rating in mph
Wind/recoil is wind rating/er

 

[wind gypsy]

Cross posting this post I made in another thread. No judgement on cartridges here, just some rough numbers and my attempt to quantify the "wind number vs recoil" question.

Looks like you've got an error on the 28nos data.

 

[ThatDUDE]

I was in a similar vein of thought. The 6.5 Creedmoor with a 147 started at 2600, according to Strelok, bucks the wind better then a 6mm 109 started at 2900. The difference was 2” at 600 yards. Everything I have been reading points to that extra recoil of the 6.5 not being worth it.

 

[solarshooter]

Looks like you've got an error on the 28nos data.

See comment there, adjusted powder effect to account for muzzle brake and actual felt recoil. It kicks about the same as the 284 unbraked, so I scaled powder charge by 0.25.

 

[Dioni A]

I'd like to see video evidence.

Lol. I'm the owner of the 6.5 PRC shooting the really hot load with 147s. It didn't help as much as I thought it was going to. A stupid fast 22 cal or 6mm is the way.

 

[Dioni A]

I was in a similar vein of thought. The 6.5 Creedmoor with a 147 started at 2600, according to Strelok, bucks the wind better then a 6mm 109 started at 2900. The difference was 2” at 600 yards. Everything I have been reading points to that extra recoil of the 6.5 not being worth it.

A 147 at 3100 is sporty in the wind. A 108 eldm at 3300+ or an 88 ELDM going 3300+ is a better all around solution though.

Edit* 3200+ is probably more reasonable on the 22 creed.

 

[Sadler]

A 147 at 3100 is sporty in the wind. A 108 eldm at 3300+ or an 88 ELDM going 3300+ is a better all around solution though.

Speaking of an 88eldm going 3300+, are you doing that with the creedmoor or did you get a 22UM?

 

[willfrye027]

A 147 at 3100 is sporty in the wind. A 108 eldm at 3300+ or an 88 ELDM going 3300+ is a better all around solution though.

How’d that tikka heavy varmint 22 creedmoor end up shooting?

 

[Dioni A]

Speaking of an 88eldm going 3300+, are you doing that with the creedmoor or did you get a 22UM?

Going to see how hard I can run a creedmoor. There may be a new um solution in the future. Have to see if it comes to fruition though.

 

[Dioni A]

How’d that tikka heavy varmint 22 creedmoor end up shooting?

That's the one form was referring to. It didn't like eldms but shoots Bergers really well. It's like a cheat code. I won't be surprised if it shot out by the end of the summer. My buddy's been shooting it a bunch.

 

[willfrye027]

That's the one form was referring to. It didn't like eldms but shoots Bergers really well. It's like a cheat code. I won't be surprised if it shot out by the end of the summer. My buddy's been shooting it a bunch.

I guess if it doesn’t like ELDMs he might as well shoot it out as fast as possible