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

I don't think there can be parallax with irons, but it would be the same as bad sight alignment.

To be clear on stability and bullets 'going to sleep'...
It's completely normal for bullets to come out of the muzzle with some disturbance or 'tip off' due to barrel whip, gas escape, imbalance, etc. When this happens, a stable bullet will settle and dampen it's yaw down as it flies.

However, the helical/corkscrew flight path that results from this motion is so very minor (about 1/10th of one caliber) that it simply doesn't explain the magnitude of group convergence that is often reported.

-Bryan

Bryan
Thanks for the information-

Your name is on my ballistic app thingy.



Travis

Jeff,
Re: parallex with irons. There's a fellow competitor/engineer a similar question and posted a white paper. I think he was challenging the importance of sight alignment. I'll see if I can find a link...or try googling Robert Burge, iron sights.

Yours is on three overpasses between Cheyenne and Cody.

Country gals. Always braggin'.



Travis

Thats all it is in optics... non alignment.

Without that with irons you can't shoot a group. Pretty simple.

Since I could shoot gropus in the day, and according to some laser thingy my prone slung up wobble was very minimal, I'd think my results of shooting were repeatable enough.

Damn shame, you are getting me itchy again, but it simply won't happen unfortunately....at least not for some years.

Jeff,
Here's a link to the Iron Sight/Parallax article I had mentioned;
http://www.biathlon.net/Aperture_Sight.pdf

BTW, I still have two 6.5 twist uppers. One is set up for strain pressures. (remember that one?) and the other has maybe 2000 rounds on it. Would you want me to send one of them to Texas for 90JLK load work-ups to see if you can recreate the effect with my upper?

...follow up article.
http://dougkerr.net/pumpkin/articles/Aperture_Sight_Demo.pdf

I have an early 56 or 57' Winchester Varminter in .243, I noticed it loved federal prem70 gr BT's, I was able to buy the last 9 boxes left from the case of the first box that shot so well.the gun and ammo was sub moa at 100 about a solid .75 inch 5 shot on clear ,cool and calm days.At 300 yards it would and still will shoot 1 1/8" group if I am 'on'. I have 3 boxes,60 rounds left and smile every time I see them in the back of the ammo storage.. As hard as I have tried I just can tie the 300 yard 5 shot groups at 200 yards. Old timer shooters explained it to mr as the bullets going to sleep out past the 100 yards, I never questioned I just smiled the old school gun and factory ammo will still 'do it' if Im on! very best WinPoor


old50,1,2and300yardrange,

I have a 243 with a 1-8 inch twist #3 bartlein barel, shooting 105 gr berger hybrids. Have shot a 243 for 20 years, but this is a new barrel, about 6 months old. It shoots .5 to .6 at 100 yds.What is interesting is that it shoots the same group size, at 200yds. It simply doesn't change. Have replicated this 3 times now. You would think that the group size should increase as distance increases. Have not shot a bench group at 300 to see there. Any thoughts?

Yes. Shoot it at 300....

Thanks for that article and the one below, I'll have to make time to read it.

I appreciate the upper offer, but my life simply does not have time to do things like this right now. Vol Fire/EMS burns most of my time that I have to spare. Even find it hard to find time to work up a hunting load for a new rifle or even bed and work on the trigger.... Unfortunately between that, caring for parents, the 100 acres maintenance, and a job that is requiring more schooling and so on... just isn't time right now.

I hate that, but its life.

Thanks, Jeff

1) Watch arrows in slow motion as being released from a bow. They come out with lots of side to side movement but, they stabilize the further out they get, to a point, when they again become unstable, I believe due to a loss of spin. If you shoot one up in the sky by the time they come down they are wobbling. They start out wobbling, they stabilize, then they begin again as spin drops off.

2) Remove twist and shoot a projectile out of a smoothbore and what differences do you see? I suspect chaos.

3) Spin a toy top on a table and what happens?

I have no problem seeing a bullet stabilizing due to the SPIN relentlessly trying to "center" it, and not necessarily at OUR arbitrary 100 yards. With barrel weights, lengths, twists, construction, and projectile construction, weight, and velocities I would imagine there would be too many variables to predict at what range a given load would be the most "accurate" or centered.

The experiment that needs to be conducted is what happens to a projectile at varying rates of twist, right down to no twist. That would shed some light on things.

Watch this 7 second video. If you think arrows only fly worse after they leave the bow, in ever widening circles, you would be wrong.

Exactly, I never could understand why this line of reasoning still continues to exist.

I had a rifle that was shooting 300 yd groups that were consistently larger than they should have been. The culprit was when In focus at 300 yds the parralax was way off. I fixed the issue by adjusting the parralax out of the scope first then focused the eye peice. I believe 99% of this phenomenon is a parralax issue or related to a mirage issue caused by optics or even ones own eyes.

Shod

Again, no critical thought. Think about it. Yes the arrows are flexing, but no one, and I do mean NO ONE in archery competition thinks that a bow will shoot smaller groups at 20 yards than at 10 yards. Nor if they are tuned right will they shoot smaller groups at 40 yards than at 20. And then think about that a bullet ain't flexing. It is launched from the muzzle in a particular direction. It can't magically pull itself back into the bore line.

Agreed. That archery link has zero to do with the topic at hand. Not same thing, nor close......

Because those convinced they can shoot better groups at long range than up close have repeated that fallacy until they believe it themselves

Bullets are also void of fletching to drag in the air and slow down the spin rate....