Can't get my head around this

[rscott5028]

Litz/Berger did do a 'mythbuster' on the elliptical swerving notions. It only happens within feet of muzzle release and ain't causing decreasing moa, or anything else -decreasing.

I am one of 'those shooters' who consistently shoot tighter grouping in moa with distance.
I can't prove anything, but I believe it's scope parallax.
This passes more tests..

I also consistently shoot with scopes at 25x or higher, and I wear prescription glasses.
Any gun I shoot tighter at distance with, holds growing moa(as expected) when my son shoots them.
He has eagle eyes, perfect method, and is a far better 100-200yrd shooter than I. But I catch up by 500yds!

I've thought about it alot. Notice while shooting through glasses that there is just this little tiny area on the edge of the shooting eye lens that has to be focused through. This area NEVER matches a center lens prescription. That may be significant. Also, setting parallax on a scope is much easier and precise with growing distance. Our brains adjust vision to focus even with a relatively bad parallax setting -up close. But at distance, anything other than dead on seems blurry and moves more with head movement.
There is no band to play with at distance, that a brain could quickly adjust to.

Anyway, it's my theory, but I cannot acquire a solution from local lens-flippers...

Now, that's an explanation that I can buy into.

 

[rscott5028]

Litz/Berger did do a 'mythbuster' on the elliptical swerving notions. It only happens within feet of muzzle release and ain't causing decreasing moa, or anything else -decreasing.

Mikecr is right. Litz did debunk this myth fairly adequately in this article.
Epicyclic Swerve

The OP references the URL (Bullet Dispersions) which states that...

So, if the Swerve component is on the order of 0.25", it stays at this level, or gets slightly bigger as the bullet goes down range. If you keep the Jump error small then this is what you will observe, a 0.5" group at 100, and 0.5" at 200, etc. Here is where you can see that the MOA can actually decrease at longer ranges. The group size never decreases, but the dispersion in terms of MOA does. A subtle but important difference.

Litz also cites McCoy who was referenced in the URL (Bullet Dispersions) and does a good job of putting McCoy's work back into perspective as that particular URL takes it out of context.

Yes. Epicyclic Swerve exists.
No. It's not enough to cause decreasing MOA or group sizes at longer range.
Myth busted.

However, as others have observed, decreasing MOA at longer ranges can occur due to other factors such as parallax adjustment.

-- richard