Home Forums Hunting & Shooting Long Range Hunting Smaller dispersion at longer range than at close range.

One of these two illustrations should help as well. The first is very important.







Some prefer this explanation of the phenomena. I like this angle of dispersion, but think the the muzzle blast would definitely cause shrinkage well after the fact. Adding some Yaw will help if you don't seat the projectile concentrically







just a thought

Nice recoil pad.........

Here's a simplified explanation of "Positive Compensation" which would help explain the phenomenon in the vertical plane.



I think rcamuglia is using Varmint Al to invoke the above principle.

Chris

Its not in the cards for me to get to MI at this point in my life.

But there is always the next 9 years of slavery and then retirement.... then it could happen.

Now that I"ve read some more....

I may not recall exactly, but what drove me nuts was with the 90s, it would seem you could work a group down to around 3 inches at 600. 5 shot and 10 shot groups would be about the same, this after a LOT of shooting groups to confirm and running lots of 10+1 and 10+1 tests at 600 out of the sling in 22 shot matches(yes that didn't follow rules to a T....)

BUT IIRC the 90s also held about the same 3 inch group at 300 that they did at 600.

I"d bet the 300 yard group shot over time might be more like 2.5 inches and the 600s might even average a bit larger than 3 but for all practical purposes it was the same. 3 at 600 is fine. 3 at 300 is puke.

Please wish the family Merry Christmas from Carolyn and I!

Jeff

Obviously the flaw there is use of too much powder, making the projectile rise after leaving the bore. The pressure required to match that graph is generally to hard on the bullet bases and will knock the accuracy out of the park so that it really doesn't matter that its rising instead of falling.

Thankfully mine generally does fall after its risen, but it has a useful half life in there long enough to make me happy... but I digress

Jeff,
Would you consider sending your rifle and some ammo to Michigan? I might even be able to to contribute some JLK 90's for the effort.

That would not be a big deal, unfortunately I don't have those anymore.

Damn it I wish I did. I have some uppers left but both 90 uppers were shot out, all I have is capable by the 7 twist and 75/80s and those never really showed that much to me. It would to an extent by a small margin but nothing enough to scratch my head over.

I should fact check my posts before I post them:(


I was buying scopes from you out of shotgun news in the 90s.
Last year I bought this rifle from your company.
Right now I am ordering from you Weaver S46 and S54 bases to mill off the radius on the bottom to put on these Dumoulin receivers I bought:


Did someone says something about quantum mechanics?
I am wondering if human observation decreases entropy, and so causes electron or photon "waveform collapse".

�When you have eliminated the impossible, whatever remains, however improbable, must be the truth,� said Sherlock Holmes.

Clark,
Your original unedited post was a nice trip down internet memory lane. But I would not be the scope peddlin' ChrisF...(although I do have some definite opinions about spotting scopes!)

Ironically, if you check the yarchive.net site of usenet archives, you'll find that Gale McMillan was quite the optics tinkerer/entrepreneur.

I'm actually thinking "string theory"...but I keep asking myself, how long a piece of twine do you need to pull the bullet back on course?

I just read the wikipedia page on string theory. That did not do me any good. The room is still spinning.

~ 15 years ago I got some emails from Gale about scopes. That was 5 computers ago, so all we have is my poor memory.

He suggested I buy Leupold and Bausch and Lomb.
That is all I remember right now. I blame the bad memory function on that wiki page. But I remember a lot of his post about going to Asia for his scope contract with the Marines.

My father got a couple contracts with the marines. The XM70 is the only one with internet exposure now. He was proud of the constant recoil over 6 shots he got.
http://www.liveleak.com/view?i=511_1347383868

Clark is that a B78? BTW, I think you're supposed to shred those files, not shoot them...and BBTW, I think you shot your chrono too! It looks like it keeled over!


I think it's a truism that "human intervention decreases entropy"...but the real question is whether pulling the string or pulling my finger will get the bullet back on course?

That 2500 feet and a clear day, the sky is too black for that chrono to trip. So I point it at something white, and it trips.

If I were to design a chronograph, I would do it magnetically, not with opto diodes.

If I were to design the power supply in this computer, I would make a forward converter with FETs, not a 1980s style half bridge with bipolars.

But then everything would cost more.

Hey guys,

Glad to see this topic is getting traction here.

Remember, the objective at this point is to determine, experimentally, IF group convergence happens as claimed. If it does, THEN we can have long discussions about how it happens. Typically, the internet discussions put the cart before the horse and there are many discussions/arguments about how it happens with little effort spent to determine IF it really happens in the first place.

That's the intent of the Applied Ballistics Shoot Thru Target Challenge.

If extensive live fire testing shows that group convergence isn't really happening, then we can have far more productive discussions about what really IS happening, and how to address it.

Please spread the word about this challenge to anyone you know that believes in converging groups. The shoot thru target will either convert them, or demonstrate the phenomena to be real. Either result would be progress from where we are now.

Thanks guys,
-Bryan

Shooting is the proper method here.

Lest one could be labeled a shredophile.

I admit to squeezing a few triggers of a few guns at LR in my day. I have never, ever, ever, had a rifle that shot tighter groups further away. Ever.

To be honest, the mere thought of it makes no sense and I would immediately call BS when hearing of such a report.

That said, I used to be an avid reader of anything Gale McMillan I could find. He didn't guess at stuff much. Needless to say, I find his post to be, at the very least, thought provoking.

However, and forgive me if I did not do a thorough enough job reading this thread, I'm assuming that nobody has ever actually been able to PROVE the bullet path to be anything but directly lineal?

No, it's never been proven/demonstrated. That's what the 'challenge' is about.

It's commonly reported that a shooter/rifle will generate smaller MOA groups at longer ranges; HOWEVER, the true cause has never been discovered. Some people believe the bullets actually fly that way, others believe optics, or statistical chance is the cause. The intent of the shoot thru target is to discover if bullets actually fly that way. So far, based on dozens of groups fired from .224 thru .408 cal, they haven't.

-Bryan

Mr Litz,

Off topic...

Have not tried your tall target test yet due to limited time. But I soon will be. Great application of ivory tower math to real world stuff. Glad to see you posting here.

I have always thought this to be the answer to tiny groups at 300 but so so at 100. Improper adjustments of the parallax. My good friend espouses the bullet going to sleep idea, (gyroscopic procession???) but I don't buy it.

Now that there is a way to test, I oh so wish I still had the uppers that did this.

A shame but will be 9 years more until I"d hvae time and resources to play with it again.

Now would be PERFECT timing.

Its so obvious on paper, but there also never was anyone that could answer why.

I"ve never asked, but is parallax present in irons, thats all we ever shot in competition....