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Big Browns

G7 Rangefinder is AWESOME!!!!

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Everyone north of the equator the shot will always be right no matter which way you are facing due to coriolis.

That is not exactly accurate. (pun intended) Coriolis is pretty complicated when it comes to figuring exact displacement of a shot. For example... it has more of an effect near the equator than it would near a pole (North or South), a shot directly north or south will print substantially more movement then one fired directly east or west.

 

Spin drift is more of a constant, but can change with altitude/air density.

 

I feel when speaking about the vast majority of "long range shooters" .3 MOA deviation at ranges of or exceeding 1000 yds would be EXTREMELY hard to pin down to one culprit or eliminate. An even slightly canted scope or rifle could easily be responsible for 1/2 MOA deviation, not to mention the multitude of other factors like wind, mirage, air density, spin drift, etc, or a loose nut behind the trigger.

 

If a guy controls what he can, and coriolis was the only thing unaccounted for then he will likely hit close enough in any hunting situation. I watch lots of long range hunting shots being made (youtube, DVDs, and TV) where coriolis is the least of the guys worries.

 

I guess what I am trying to say is if you do your due diligence at the range and at the loading bench, coriolis will not effect anything but serious extreme range shooting.

 

BIGBROWNS, Thanks for posting. I hope you get that last little bit worked out and put the hammer on a bear!

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Man that's lazy, what happened to a wet finger in the air and a pad of paper? Lol congrats on the new gear. Now go smoke some yotes at 1000

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Everyone north of the equator the shot will always be right no matter which way you are facing due to coriolis.

That is not exactly accurate. (pun intended) Coriolis is pretty complicated when it comes to figuring exact displacement of a shot. For example... it has more of an effect near the equator than it would near a pole (North or South), a shot directly north or south will print substantially more movement then one fired directly east or west.

 

Spin drift is more of a constant, but can change with altitude/air density.

 

I feel when speaking about the vast majority of "long range shooters" .3 MOA deviation at ranges of or exceeding 1000 yds would be EXTREMELY hard to pin down to one culprit or eliminate. An even slightly canted scope or rifle could easily be responsible for 1/2 MOA deviation, not to mention the multitude of other factors like wind, mirage, air density, spin drift, etc, or a loose nut behind the trigger.

 

If a guy controls what he can, and coriolis was the only thing unaccounted for then he will likely hit close enough in any hunting situation. I watch lots of long range hunting shots being made (youtube, DVDs, and TV) where coriolis is the least of the guys worries.

 

I guess what I am trying to say is if you do your due diligence at the range and at the loading bench, coriolis will not effect anything but serious extreme range shooting.

 

BIGBROWNS, Thanks for posting. I hope you get that last little bit worked out and put the hammer on a bear!

 

 

Good stuff! Not aimed at this conversation or BB but I see trigger pull and rifle cant as the main culprits when I am out with some of the impatient buddies I shoot with. Of course I avoid saying that so as not to get them all spun up questioning their manhood. Also, these are not typically guys shooting over 500 yards.

 

I use the shooter app and turn on spin drift and coriolis.

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Good stuff! Not aimed at this conversation or BB but I see trigger pull and rifle cant as the main culprits when I am out with some of the impatient buddies I shoot with. Of course I avoid saying that so as not to get them all spun up questioning their manhood. Also, these are not typically guys shooting over 500 yards.

 

I hope I didn't sound like I was aiming my comments at anyone either. Just wanted to say in general a guy could go crazy chasing down .3-.5 MOA at 1K thinking it was coriolis, when it could be a simpler problem to remedy.

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I don't think anyone is offended. This is all great info! It never hurts to hear numberous views and oppinions on long range shooting. We are all eager to learn how to become more profeciant long range shooters.....

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BR2 is a nice tool. They came out with a new version ranging to 2500 yds and milrad. I like mine and have 1 more range trip to lock it down.

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Does the new version give you a solution past 1400 yrds? Been having to use exball on my PDA or shooters past 1400 yrds. On wind I use a kestrel 3500.then enter it in shooters or exball with spin drift already added. to the program. The BR2 wind dope leaves a lot to be desired. For hunting its hard to beat the BR2 for speed when setting up for the shot.Just have your wind dope ready to go.Been using one for couple of years and got no complaints.Also make sure you validate it out to whatever range you plan to shoot.

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Have you guys noticed any discrepancies for the G7 and your actual muzzle velocity? Meaning are you having to put a different muzzle velocity than you have actually

Measured?

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Have you guys noticed any discrepancies for the G7 and your actual muzzle velocity? Meaning are you having to put a different muzzle velocity than you have actually

Measured?

Becker,

Can you elaborate on what you mean by mesured?

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I notice this Becker. I assumed that the chrono was not 100percent accurate and I need to adjust speed to get proper actual dope. At 1k my drop was far less then projected by chrono numbers. Speed the velocity up to match drop, changed on br2, and then boom! I believe that's why the guys at gunworks stress to field verify drop apposed to just going off chrono numbers. The chrono we had wouldn't detect my 22-250 speeds I had to rely solely on drop to get my speeds. I was using the shooter app and just adjusting velocity till it matched drop.

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I notice this Becker. I assumed that the chrono was not 100percent accurate and I need to adjust speed to get proper actual dope. At 1k my drop was far less then projected by chrono numbers. Speed the velocity up to match drop, changed on br2, and then boom! I believe that's why the guys at gunworks stress to field verify drop apposed to just going off chrono numbers. The chrono we had wouldn't detect my 22-250 speeds I had to rely solely on drop to get my speeds. I was using the shooter app and just adjusting velocity till it matched drop.

Chronographs will get you really really close to your actual muzzle velocity. However it's only 1/2 of what's really going on when you build the first drop chart that isnt 100% and needs corrected. Published BC's aren't 100% accurate either and is just as much a culprit to your data being initially off as the velocity. In some cases published BC's are exadurated and in some cases understated. Example: Hornady has recently found more accurate way to mesure BC. A bullets BC is shed in flight and their new Doppler system they can now mesure this more accuray than ever before. Hornady has recently updated the published BC for their bullets on their website because of this. That being said you can correct a shooting solution or (drop chart) by adjusting the input of BC just as well as you can by adjusting velocity. We choose to correct Velocity because it's just easier. So when you adjust velocity it doesn't mean your bullet isn't doing the speed the chronograph is reading it's just the number we tweek to make the actual trajectory work out.

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I completely under stand the whole velocity and BC querks. Also understand the chronograph error. Just was curious as to how much difference you guys were having to enter (if any) based on chrono readings or shooter apps. My first load for my gun I had to adjust slightly than what my chronograph said. Haven't got my new load tested out to 1000 for verification just yet. Although I did take a shot at my 12" gong at 1086 yards the other day with initial values entered and hit it. Soooo I'm close.

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I completely under stand the whole velocity and BC querks. Also understand the chronograph error. Just was curious as to how much difference you guys were having to enter (if any) based on chrono readings or shooter apps. My first load for my gun I had to adjust slightly than what my chronograph said. Haven't got my new load tested out to 1000 for verification just yet. Although I did take a shot at my 12" gong at 1086 yards the other day with initial values entered and hit it. Soooo I'm close.

The last one I did for a 7 Rem Mag I had to bump the Velocity up 70 FPS. from the chronograph readings.

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