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Rohann
01-23-2005, 08:59 PM
Hey everyone, me again.
Can someone explain parallax to me? I know that it is "when the reticle doesn't line up where it is supposed to", but I was wondering if I would need a scope with parallax adjustment for shooting at ranges over 200 yards.
Also, does a focus adjustment work the same as a parallax adjustment? Is this the same as an AO?

Thanks,
-Rohann

rockinbbar
01-23-2005, 10:29 PM
Rohann,

One good way to get an example of parallax is to put your rifle on sand bags....Line the crosshairs up in the center of the bullseye, then without moving the rifle, move your head slightly to the side & up & down while looking through the scope. If the crosshairs "move around" the bulseye, then you have a paralaxx problem.... If they stay pretty much where you put them, the parralax is fine for that range.
Some cheaper scopes REALLY have lots of parralax, thus rendering them incapable of producing good groups unless you have your eye at the EXACT point each time you shoot...

That is one reason I really like Leupold scopes.
I never buy a scope unless I check the parallax movement. You can do this simple ebough in Walmart, or your gunshop. Just set the scope on a level surface & move it to crosshair on something across the store, or out a window....Move your head around & see if the crosshairs jump off the target you focused on... If it does, then pass on the scope.

Some cheaper scopes will move the crosshairs as you change from say 3X to 9X as well...
They are junk & cannot be trusted.

I group well with my 4-12 Leupold, whether it is 50 yards, or 300 yards....4 or 12 power.
Remember, your rifle is only going to be as accurate as the scope you mount on it.....
It always amazes me that someone will spend $650 on a real nice rifle, then put a $75 cheap scope on it....You get what you pay for....
Hope this helps some.

Rockinbbar

HARRY SACZ
01-24-2005, 02:37 AM
I have a 40.00 scope on my rifle i wonder if that is my problem?

CAfrica
01-24-2005, 02:38 AM
Some explanation on parallax.

Every scope is made to have its parallax at a certain distance. This is the distance at which the crosshairs are in the "same plane" as the target. Most scopes are generally set to 100 yards. The paraallax position is also the position where you will have the least "distortion" between what you actually see in relation to what should be (i.e. in rockinbbar's example, at the parallax focus point, you will have the least movement when you move your eye around).

Parallax adjustment scopes simply means that it allows you to move the parrallax focus point. I blieve this is overkill for a hunting scope, might be useful for a loing range target scope (or for those guys who do real long range hunting (Beanfield hunting)).

The problem with some of the cheaper scopes is that the nparallax focus point is 25yards or 50 yards and these are the scopes that are unreliable.

Rockinbbar is right, never put a "cheap" scope on your rifle (cheap does not refer to price, it refers to quality).

C

HARRY SACZ
01-24-2005, 02:45 AM
I just cant get any good groups out of my rifle. I meen sometimes i do but most of the time i have one shot way off. I have never checked in between shots to see if it is my 1st,2nd or 3rd shot that is so far off. But then maybe its just me.

Rohann
01-24-2005, 02:53 PM
Harry: What range are you shooting at? What are you using for a rest?

Thanks for the advice Rockinbbar and CAfrica. I am looking for a scope that I can do longe range shooting with, so I think I'll look for one with an AO.
Don't all Leupolds come with an AO?

Thanks,
-Rohann

HARRY SACZ
01-24-2005, 02:59 PM
Two hundred yards with a bipod

Marlin917VS
01-24-2005, 04:18 PM
All leupolds don't come with AO. I think leupolds are set parallax free at 150 unless they have AO. I have a swift 6-24x50 on my 17hmr and I don't know how I got by without AO on my other scopes. That just makes it so much nicer. Later

Rohann
01-24-2005, 06:19 PM
Oh ok thanks. Yeah I'll look for a scope with an AO. Is an AO the same this as a focus adjustment?

Harry: To test the rifle/scope for accuracy, get yourself a sturdy rest, and with a few different types of ammo, shoot 5-shot groups at 100 yards (first, sight the rifle in at 100 yards with a certain type of ammo. Don't adjust the scope after doing this until shooting is finished.)
Hope this helps,

-Rohann

CAfrica
06-21-2005, 01:12 AM
I want to revive this thread. I would like opinion on the following.

On several occasions I have personally experienced this or seen the same result with other people. You walk up to a downed animal that is still alive, you want to administer the Coup de Grace but don't have your handgun with you. So you up with your scoped hunting rifle and at a range of about 3 to 4 yards you miss the head completely (or hit significantly away from your POA).

Theoretically, you should be hitting about 1.5" below POA but this does not happen. The only explanation I have been able to come up with is that this is as a result of the parallax error at such close range.

Comment?

C

Marlin917VS
06-21-2005, 01:06 PM
That happened to me with my first deer. It was facing me for my first shot and I hit it in the jaw/nose and it was moving a little after I got up to it (not just twitching) so I went to put one in the middle of the neck and I ended up hitting the very top of the neck (maybe 3 inches higher than I aimed). I never thought about that being from parallax, but it could be. Since I've never shot in the position when at the range before, my eye was probably in a different place, and that plus being 4 yards away could make you miss by a lot.

Later
Andy

Rohann
06-21-2005, 06:24 PM
This happened to my friends brother while hunting Springbok in SA. He aimed at the deer's head after downing it, and ended up shooting off it's jaw (which I heard was quite gruesome, they ended up having to shoot it again).
There are many scopes out there that have parallax set from 50-Infinity or 50-150, etc. If a scope doesn't have an AO, the parallax is usually set to 50 yards on centerfire rifle scopes.

-Rohann

Marlin917VS
06-21-2005, 07:33 PM
Actually most centerfire scopes with out adjustable AO are set between 100 and 150, rimfires are usually set betwee 30 and 75.

Rohann
06-21-2005, 07:44 PM
Oh my mistake; a lot of centerfire scopes with AO's or focus-type adjustments are set from 50yards-infinity.

-Rohann

azhdryder
06-21-2005, 08:16 PM
If you get the Leupold, get a 30mm tube w/ a side focus and stop worrying so much. RB explained very eloquently what I had written over alot of pages. He was able to convert the physics to reality very well, thank you RB.

You WILL have to move or otherwise change positions to monkey w/ an adjustable Objective. You really dont need one, read the book and learn. Its explained very well. Buy the MkIV and be happy. You will never regret it, I promise:)

Rohann
06-21-2005, 08:52 PM
Thanks.
Yeah I know it's not a problem, side focus worked very well for me when I used an Mk4 M3 a few weekends ago. The question was just brought up about close range parallax.

Regards,
-Rohann

azhdryder
06-21-2005, 10:15 PM
Ya know, if you arent carefull you'll fall in love with good glass and spend all your money on optics like the rest of us. If you arent very carefull

Rohann
06-22-2005, 06:45 PM
Heh heh I'm sure that's what will happen, I'm prepared to spend more on quality optics and mounts than on my base rifle.

-Rohann

sakorick
06-26-2005, 10:27 PM
Heh heh I'm sure that's what will happen, I'm prepared to spend more on quality optics and mounts than on my base rifle.

-Rohann
Bingo...for a youngster, you're learning fast...take a 1500 dollar sako finnbear deluxe and put on a cheap set of redfield mounts and a cheap Tasco and....you have a 1700 dollar nightmare.

Take a 400 dollar remington adl, put on a nice pair of S&K rings with a Zeiss scope and .....you've got a 1200 dollar killing machine!!!!!

Regards, Rick.:D

Rohann
06-27-2005, 05:30 PM
:D

-Rohann

JTapia
06-28-2005, 11:59 PM
Just to add to Rohanns comments to Harry,
You dont necessarily need to zero in your scope to test for accuracy. Start by just locking down the rifle and shoot a couple of 5 shot groups and see where you are at, grouping wise, and certainly look after each shot to check for "wildcats" and which shot the wildcat appeared. Then check for a pattern to the wildcats. for example, if it seems to happen on the third shot then increase the time between shots to allow the barrel to cool and see if that cures the wildcats. If that doesn't do it then try different brands of ammo. My remington 760 wont shoot remington ammo (go figure) but my mossberg 30.06 does just fine with remington ammo.
One last note, a good many rifles have been ruined by not properly "seasoning" or breaking them in. What ever you do dont go buy a new rifle and 3 boxes of ammo and go to the range and shoot until you are out of bullets. Go slow and easy, allowing he barrel to stay cool and space out the number of cartridges shot thru the new rifle over a few trips to the range. It'll pay huge dividends in accuracy down the road.

Rohann
06-29-2005, 11:40 AM
Thanks for the post, I'll keep that in mind.

-Rohann

akpride
03-09-2006, 01:02 PM
so can there be such things. as 100% parallax free beyond 50 meters

azhdryder
03-10-2006, 09:49 PM
Ok, somebody had to bring this up again. In a quality scope, like Leupold MK4, the amount of paralax possible is so minute its almost unmeasurable without a machine rest ( no stock, receiver fixed on a rail) to the tune of 1.5 inches, not MOA at 500 meters. This from a factory Leupold rep at an optics show. This was backed up by other factory reps from Burris and Ziess. Paralax in a QUALITY scope is not going to be an issue farther out than 10-15 yards. In close its not paralax , but the difference in line of bore/line of sight and shooter error compounding the problem. In short, if you spend your money wisely, worry about everything other than paralax.