Range finder plus wind meter

Wachsmann

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Joined
Feb 1, 2008
Messages
984
Location
Idaho
I hear you. I had a buck that didn’t want to stand still and I was messing with the range, ballistic app and wind. He finally gave me a still shot at 761 or 861. Anyways last thing I forgot to do was adjust for the wind. Hit the buck in the back part of the ribs but still a good enough kill shot. Bullet had pushed about 3 inches and I suspect I had a little to do with the the other 2 inches so total of about 5 inches from where the crease was. Still put him down in his tracks (300RUM). 220ELDX. But yes range some spots and getting an ideal of different distance in the area helps a lot.
 

QuietTexan

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Nov 16, 2020
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1,037
Location
Fort Worth, Texas
MPBR brackets are great for hunting because the vitals zone is large enough to make range less impactful on a shot than wind. You figure out progressively longer "zeros" of something like 100 - 200 - 450 - 700, and the bracket on each range keeps you within +/-4" of POA=POI.
100 yard zero - baseline
0-350 yards - up 0.9 mil (+0.9 total)
350-550 yards - up 1.2 mil (+2.1 total)
550-850 yards - up 1.7 mil (+3.9total)
 

LRNut

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Joined
Dec 4, 2004
Messages
498
Location
Arizona/Colorado
The wind is the important part. All the other stats matter but not nearly as much - a 10,000 ft change in DA is just over 0.1 mils of vertical adjustment for my load, arguably within the error range of shooting from a field position and not major when you're looking at an 8" vitals zone on an animal. But blowing the wind call by 5mph can put you off by a half mil horizontally, five times as much error in the shot. A bad wind call will reduce your hit probability by half, whereas being off on your atmospherics barely moves the needle if your range is within +/- 5 yards, which most consumer range finders will do inside 800 yards. Unless you play wind reading games and can guess within +/-3mph already, the Kestrel will actually be more helpful in increasing first round hit probabilities than the range finder itself.

QuietTexan also posted:
MPBR brackets are great for hunting because the vitals zone is large enough to make range less impactful on a shot than wind. You figure out progressively longer "zeros" of something like 100 - 200 - 450 - 700, and the bracket on each range keeps you within +/-4" of POA=POI.
100 yard zero - baseline
0-350 yards - up 0.9 mil (+0.9 total)
350-550 yards - up 1.2 mil (+2.1 total)
550-850 yards - up 1.7 mil (+3.9total)

A 10,000 ft change in DA is .1 mils? It is a lot more than that at 700 yards, and even more at 900 or farther. At 850 yards the difference for a 28 Nosler is almost 2 MOA. I know from experience because I shoot at elevations of 8750 and 1400 year round.

I also don't understand your MPBR brackets above. Are you saying from 550 to 850 you dial up 3.9 mils for any shot in this range bracket? Even if it kept you within 4" half your bullets are going to hit above or below that, which is going to cause a vertical miss half the time. A 28 Nosler launching a 195 at 2995 requires 7.6 MOA (or 2.1 mils) of elevation. At 850 the number is 16.1 MOA or 4.47 mils. Splitting the difference would be 3.3 mils (rounded to nearest .1), which means you are 1.2 mils high at 550 and 1.1 mils low at 850, which is a miss on both counts. There is nearly 100 inches of total drop difference between 550 and 850.

What am I missing?
 

QuietTexan

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Joined
Nov 16, 2020
Messages
1,037
Location
Fort Worth, Texas
What am I missing?
I misspoke, those brackets I copied in are for MPBR holds in Mils, not inches. Those are not actually based on an 8" vital zone, they're a 1mil hold over/under for my 300 RUM load. If I ran everything again those should work out to a maximum 30" vertical dispersion at 850 yards. Based on the body size of a normal elk the hold is never off the body of the animal.
 

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