[sgtdeath66]

im over on rimfire central and someone has a ? about their cross hairs moving an inch or so when they move their head ok, now that wouldnt be a parallax problem would it? i said that was more of an eye releif setting. am i right or wrong?

 

[Ram Rod]

I'd say you're right on there. Eye releif, magnification, and focus. I'd say the scope was too close to the shooter's eye.

 

[stalkingbear]

If the reticle appears to actually move around on the target itself when moving head, it is parallax problem, that means the parallax is adjusted incorrect for that distance. Most factories adjust scopes meant to be mounted on centerfire rifles to be parallax free at 100-150 yards, whereas rimfire scopes are adjusted at factory to be parallax free at 50 yards. Buying a scope featuring adjustable objective or side focus will eliminate this problem as it can then be user adjusted to be parallax free at different distances-even though the methods are actually different.

 

[sgtdeath66]

If the reticle appears to actually move around on the target itself when moving head, it is parallax problem, that means the parallax is adjusted incorrect for that distance. Most factories adjust scopes meant to be mounted on centerfire rifles to be parallax free at 100-150 yards, whereas rimfire scopes are adjusted at factory to be parallax free at 50 yards. Buying a scope featuring adjustable objective or side focus will eliminate this problem as it can then be user adjusted to be parallax free at different distances-even though the methods are actually different.

ok but you cant adjust the parallax by adjusting the occular lens am i correct?

 

[stalkingbear]

No, you can adjust focus but not parallax. Parallax can be adjusted either by factory, adjusting objective lens, or side focus-on models featuring adjustable front focus. By adjusting rear lens, you can focus image, but not parallax.

 

[sgtdeath66]

thats what i thought. this guy on rfc swears that you can change the parallax by the occular lens.thanx for the info

 

[supergus]

I was thinking of a 4x scope that is parallax free from 50 yds and out for my AR. Wouldn't that solve the problems described above. Parallax free means that no matter where your eye is in relation to the reticle, it will always be on target, right? I'm new at the optics thing and there are so many choices out there. I'd like something that'll let me hit out to several hundred yards. any suggestions on a sub- $500 scope that'll do the trick? BTW sorry for hijacking but my flat top AR should be here any time now(been 4 months) and I want to have a scope ready to install.

 

[SlamFire]

Parallax issues don't crop up much intil you get into magnification of about 10x. The mechanics are that the retical is in one plane and the objective lens in another. So the reticle "moves" when you shift eye position.

Even so, movement of POI is only a few tenths of an inch at 100 yds. Where it begins to get critical is small varmint shooting at high magnifications and long distances.

You can Google discussions of parallax. Leupold site has a decent discussion in their user manual pdf document.