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Campfire Outfitter
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"LONG RANGE TUNE.... Here is an interesting set of trajectory plots. No matter how carefully one loads his ammo, there are going to be small differences in muzzle velocity. Consider a load with an average muzzle velocity of 2915 fps with a muzzle velocity variation of 15 fps. Then consider this load tuned for zero vertical at 100 yards that overcomes that small difference in muzzle velocity. This same load will be out of tune by 73.23-71.50=1.73 inches of vertical at 600 yards. However if the load is tuned so that there is 12.21-11.92=0.29 inches of vertical at 100 yards (with the slower muzzle velocity hitting higher) then there would be zero vertical at 600 yards. This chart is for a 6.5mm 140 gr VLD bullet with a 0.64 BC. A similar chart or table can be made for each long range load. If you are in tune for zero vertical at 100 yards, you will not be in tune for zero vertical at 600 or 1000 yards."
The people wringing their hands over Trump's rhetoric don't know what time it is in America.
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Campfire Kahuna
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Campfire Kahuna
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but but but....that can't happen....
We can keep Larry Root and all his idiotic blabber and user names on here, but we can't get Ralph back..... Whiskey Tango Foxtrot, over....
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Joined: Jul 2003
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Campfire Regular
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...Jeff, I forgot to mention the other credible example of the phenomenon in your experiences. I'll hope that you consider taking Litz up on getting up to Michigan so he can try to figure out the "why" of the happening.
Last edited by ChrisF; 12/08/14.
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Campfire Regular
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rcamuglia, that looks like Varmint Al's take on Positive Compensation.
Thanks jrh. I found it late last night on yarchives and posted it to LongRangeHunting, but didn't get a chance to post it here.
Last edited by ChrisF; 12/08/14.
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Campfire Tracker
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Campfire Tracker
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I've noticed a similar ballistic phenomenon numerous times.....
Most people tend to shoot their mouths off way better from long range, than they do up close and personal.
You better pray to the God of Skinny Punks that this wind doesn't pick up......
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Campfire Outfitter
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Campfire Outfitter
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Another long range mystery...
Ever notice how awesome some chicks look at around 40-50 yards? But then look not that awesome up close?
This is referred to as the "40 Yard Fakeout".... It's been studied in depth for years.
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Joined: Jun 2011
Posts: 10,866 Likes: 63
Campfire Outfitter
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Campfire Outfitter
Joined: Jun 2011
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Another long range mystery...
Ever notice how awesome some chicks look at around 40-50 yards? But then look not that awesome up close?
This is referred to as the "40 Yard Fakeout".... It's been studied in depth for years.
Wrongo!!! It's known as "Good from far, but far from good!"
The people wringing their hands over Trump's rhetoric don't know what time it is in America.
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Campfire 'Bwana
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Campfire 'Bwana
Joined: Jun 2006
Posts: 46,104 Likes: 6 |
You just need the right optics. Beer goggles work up close, and they work best in low light conditions.
A wise man is frequently humbled.
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Campfire Ranger
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Campfire Ranger
Joined: Feb 2005
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I bet if there was a group of chicks at 100 yds, and Dogshooter starting walking toward them, that 100 yd. group size would shrink significantly due to dispersion....
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Campfire Outfitter
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Campfire Outfitter
Joined: Jul 2013
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"LONG RANGE TUNE.... Here is an interesting set of trajectory plots. No matter how carefully one loads his ammo, there are going to be small differences in muzzle velocity. Consider a load with an average muzzle velocity of 2915 fps with a muzzle velocity variation of 15 fps. Then consider this load tuned for zero vertical at 100 yards that overcomes that small difference in muzzle velocity. This same load will be out of tune by 73.23-71.50=1.73 inches of vertical at 600 yards. However if the load is tuned so that there is 12.21-11.92=0.29 inches of vertical at 100 yards (with the slower muzzle velocity hitting higher) then there would be zero vertical at 600 yards. This chart is for a 6.5mm 140 gr VLD bullet with a 0.64 BC. A similar chart or table can be made for each long range load. If you are in tune for zero vertical at 100 yards, you will not be in tune for zero vertical at 600 or 1000 yards." This blew my mind. Way above my level of ballistics understanding! I've seen non-linear dispersion on targets between close range and longer range. Nothing so drastic as 1 moa at 100 and the same at 200, but a load that shoots a consistent .7 moa at 100 and then .5 moa past 300. Could simply be shooter error, or other variables unaccounted for. Have only seen this with very long VLD-style bullets. I don't think the linear dispersion model works with something spinning so fast, as that introduces an entirely different physics to the flight of the projectile in an atmosphere. This thread reminds me of other physical 'impossibilities' that were later proved very possible, like a human running a 4-minute mile. There are many such examples. We as a race seem to have become very egotistical about what we 'know'. If I could get past a few hurdles, I'd be tempted to take Litz's offer. Hoping someone does, because I do want to learn.
I belong on eroding granite, among the pines.
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Campfire Tracker
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Campfire Tracker
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Laffin..... the prosecution rests your Honor.....
You're right though..... not too many folks at the SRM were envious of my .260.... same can't be said of my lady.
You better pray to the God of Skinny Punks that this wind doesn't pick up......
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Campfire Ranger
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Campfire Ranger
Joined: Feb 2005
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Joined: Feb 2005
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Campfire Ranger
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Campfire Ranger
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You should be laffin', cuz it was funny
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Campfire Outfitter
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Campfire Outfitter
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... a posting by Gale McMillan on the old usenet recguns forum, which I believe was archived on yarchives. Gale did not write much on rec.guns ~~1997. When he was in bed with cancer, he wrote on the modern www forum The High Road.
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. -Ernest Hemingway The man who makes no mistakes does not usually make anything.-- Edward John Phelps
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Clark, I read your post before you edited it. I only know recguns from the yarchives, but Gale McMillans posts are very present there (as are BartB's.) Yes, I did frequent Shooters.com (mostly the Highpower board). There were some very cool discussions there (some of which like the pressure measurement discussion, I saved as pdf's and mht's). I'm not much of an optics guy but I do have a small collection of External adjust Unertl's, Remingtons, Lymans etc. I think I remember you from the old Accurate Shooter site... ClarkM, engineer from the PNW?
Last edited by ChrisF; 12/08/14.
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Campfire Outfitter
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Campfire Outfitter
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There are a few ways that quantum mechanics could also play a part in explaining what is going on with non-linear dispersion. I keep wondering if that can somehow be experimented with. I know a lot of people prefer the Newtonian physics model, even though it has been surpassed in accuracy by the Quantum model.
I belong on eroding granite, among the pines.
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Campfire Outfitter
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What if the blast at the muzzle is not upsetting the stability of the bullet or its angle of dispersion but is just nudging the stable bullet off line slightly?
A perfectly straight launched bullet nudged over/up/down .001" would cause some of the "MOA shrinkage" at longer range. Something like that could cause a .75MOA group at 100 to go on to be a .5MOA at 300. Once the bullet is out of the blast zone there is no other force but wind and air pressure to act on it.
LOL
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Joined: Feb 2005
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Campfire Ranger
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Campfire Ranger
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Anybody know where in Michigan he is located?
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Campfire Regular
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Anybody know where in Michigan he is located? Cedar Springs http://appliedballisticsllc.com/about-us/Bottom of the page.... David
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Campfire Ranger
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Campfire Ranger
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This diagram can clear up a bunch of confusion, it was a test done a few years ago and helps qualify some misunderstood ballistic phenomenon...
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