223 and wind

sniperman

lads,how much would wind affect a 223 using, lets say 55gr loads,out to and past 200 yards,lets say a 25-35 mph crosswind,reason for asking is id like to be able to go out on windy days,for the odd bunny and fox,im stuck in most days,can't seem to get a calm day for the hmr,going down the 223 route soon,thanks all;)

clivej

Best way to find out and educate yourself is to use a ballistics chart.
Just fill in the relevant info and they will give you the drop and windage for your ammo.

I use strelok on my android phone, istrelok for iphone, so I always have it in my pocket.

Nice handy one on-line at
http://gundata.org/ballistic-calculator/


Input your bullet from the drop down options
use 'advanced options' for wind input

yubabill1

out to 200yds/metres25/30 mph steady wind will not move POI outside the ribcage with 223 in my experience. Beyond that the effect becomes more significant.

You could do a lot things to beat the wind - I have tried most, including an anemometer and rangefinder - but mostly I simply stalk a bit closer or shoot into the wind when I think it might affect POI.

Jonty

75 gr would give better wind bucking performance, but there would be a bit of elevation difference.

yubabill1

Jonty wrote: »

75 gr would give better wind bucking performance, but there would be a bit of elevation difference.

Sure, but only really noticeable at extreme range IMHO.

You will do well to hit a rabbit in the ribs at 300 yds in the field with a stock gun like mine without any wind.

That's 300yds by a rangefinder.

I'm not saying it's impossible, just difficult.

I appreciate the OP wants to work at long range, not trying to put anyone off.

Cass

sniperman wrote: »

lads,how much would wind affect a 223 using, lets say 55gr loads,out to and past 200 yards,lets say a 25-35 mph crosswind,...........

1. What direction is the wind coming from?
2. Is it full, quarter, half value?
3. Is it constant or gusting?
4. Is it a clear path to your target or are there wind delfectors (trees, ditches, etc) along the path.

I'm not asking to put you on the spot, but shooting at distance requires a good deal of experience. A technique used to get you used to it is to do this:

• Use a ballistic calculator to find the drift for a full value, 10mph wind. This is your set/fallback value.
• For 5 mph use half figures.
• For 15mph use 1.5 times the set value
• For 20 mph use 2 times the set value.

Now that is for drop/pick up in wind speed. For changes in wind direction given a constant speed the same applies. It is by no means a 100% foolproof plan but for hunting, and longer shots at much larger "targets" than a bullseye you'd see in a range it'll do in pinch. It also does not require the continuous use of a BC when in the field if you memorise the variances for preset values.

For a constanly shifting wind in terms of speed, and direction then it's a different story and not one any person can give an answer to. IOW it has to be worked out in the field. However you can use the above method, after determining average speed/direction and then wait for the condition you want to fire through.


Now before i get the "that's not exactly right" allow me to explain. I have made this a simple post for a reason. much like the other thread about bullets, spin, twist rate, etc. the subject can get far, far more complicated than needs be.

I've been shooting long range stuff for quite some time and i still don't get it right all the time. That is with gear worth over €7,000, the best in optics, guns, BCs, aids, spotters, etc. My point being it's a learning curve and not one that happens over night.


Lastly, and without getting into morality here, be very, very confident of your abilities before shooting at game at any distance.

yubabill1

yubabill1 wrote: »

out to 200yds/metres25/30 mph steady wind will not move POI outside the ribcage with 223 in my experience. Beyond that the effect becomes more significant.

And I'm having second thoughts about a 30mph crosswind at 200 yds/metres. These days I know I wouldn't bother - I'd just move to get a more favourable shot, even at the expense of spooking the prey. But that's just me, I've gotten lazy and like point-and-shoot these days.

20mph will be OK (assuming you are aiming at the heart/wind blowing towards tail, naturally)

+1 to Cass's input. It's all do-able and less complex in execution than in explanation.

Sika98k

Just ran a 55gr bullet through that program clivej suggested. A 25mph 90degree wind causes just over 7 inches of drift at 150 yds and over 14 inches at 200 yds. Food for thought!

yubabill1

Sika98k wrote: »

Just ran a 55gr bullet through that program clivej suggested. A 25mph 90degree wind causes just over 7 inches of drift at 150 yds and over 14 inches at 200 yds. Food for thought!

Punch in a 69gr @3000fps muzzle vel for me, just for kicks - say 20 mph 90deg wind

Sika98k

yubabill1 wrote: »

Punch in a 69gr @3000fps muzzle vel for me, just for kicks - say 20 mph 90deg wind

Lazy bugger,open the program yourself !

4200fps

sniperman wrote: »

lads,how much would wind affect a 223 using, lets say 55gr loads,out to and past 200 yards,lets say a 25-35 mph crosswind,reason for asking is id like to be able to go out on windy days,for the odd bunny and fox,im stuck in most days,can't seem to get a calm day for the hmr,going down the 223 route soon,thanks all;)

With a wind value of 30 mph the 55 grain bullet would drift by
13inchs at 200 yards
21inches at 250 yards
33 inches at 300 yards
45 inches at 350 yards. Them calculations wouldn't be far off. They say windy nights are great for foxing lol some how a challenge in my good opinion. Anyways wind values differ from x-y, its good estimates you can go by. Hope this may be of help. You could try 75 grain loads but huge arc and your rifle may not like them or then again you could ofcoarse be lucky. Wind is a bugger not alone a breeze

yubabill1

Sika98k wrote: »

Lazy bugger,open the program yourself !

FFS

thought it was a phone app.

Been playing with it.

Says 69gr matchking will drift 8.5in @200yds, 20mph crosswind. Also says 2in drop @ 200yds with 150yd zero.

Wind drift I am prepared to concede, on the basis my memory is faulty, but I'm getting 4in drop @ 200yds, with 150yd zero using Matchkings from 24" Tikka.

Also the 75gr TAP calculates out with less wind drift (never tried wind drift with them) but found they drop 6" @ 200yds with 150yd zero.

clivej

yubabill1 wrote: »

FFS

thought it was a phone app.

Been playing with it.

Says 69gr matchking will drift 8.5in @200yds, 20mph crosswind. Also says 2in drop @ 200yds with 150yd zero.

Wind drift I am prepared to concede, on the basis my memory is faulty, but I'm getting 4in drop @ 200yds, with 150yd zero using Matchkings from 24" Tikka.

Also the 75gr TAP calculates out with less wind drift (never tried wind drift with them) but found they drop 6" @ 200yds with 150yd zero.

Just remember that bullet drop is directly related to muzzle velocity at any given distance. Less velocity = more drop. Bullets of the same material will fall at the same rate - I.E. 1lb of lead and 1ton of lead fall at the same rate.

yubabill1

clivej wrote: »

Just remember that bullet drop is directly related to muzzle velocity at any given distance. Less velocity = more drop. Bullets of the same material will fall at the same rate - I.E. 1lb of lead and 1ton of lead fall at the same rate.

I'm pretty sure I understand that, but the program underestimates bullet drop unless atmospheric conditions can double or treble the drop at 200yds - I left them at default.

As before, the wind drift could be nearer the mark - should have written my findings somewhere - wrote bullet drop on scope caps.

I am assuming I'm getting manufacturer's muzzle velocity, even though I know they use 26" test barrels - that will account for some of the disparity, I know.

Good job I avoid long range shots in 20mph wind.