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Most people seem to believe that for the money Leupold scopes take the cake. My question is, which focal plane are their reticles in? Specifically, does one HAVE to be at 10x for the mil-dots to be accurate, or will any magnification setting yield useful range estimation with their higher-end scopes? Are the two questions even related?
 

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The questions are related, but I do not have the answer to your question.

With my US Optics I got to choose, but cannot honestly now remember which is which. I'll see if I can hunt it down in my manual.

I found this on the US Optics site:

Reticles: Front or Rear Decisions
Introduction and History There are two planes of focus in the common rifle scope (lensmatic), for the placement of the reticle. They are commonly called the front focal plane and rear focal plane models. One exception is the Shepherd scope, which has both. Artillery rangefinders have always had at least two reticular focal planes, and sometimes three or four. Optical collimating scopes have always had two focal plane reticles, or aiming points. Interferometers need more than one focal plane aiming point to function.


Why front or rear focal plane placement? Question: What are focal planes and what is the difference between putting the reticle in the front or rear focal plane? Answer: Only in a variable power scope is the reticle placement a major problem. In the rear focal plane, or behind the power changing lens system (erector tube), was the first solution that occurred to optical engineers, and most American scopes are still being built that way. Unfortunately, this apparently ideal solution has a very serious flaw.

Any tolerance change in the centration of the lens system and their spherical/longitudinal movement with the power change, will shift the point of impact. A variation of one thousandth of an inch will move the zero point approximately one inch at 100 yards. Since the mechanical parts that hold the power changing lens system slide inside each other, (some allowances are made for temperature changes, manufacturing tolerances and wear), there must be some movement made to accommodate this. Consequently this lateral and vertical movement will often shift zero by as much as several inches as power is changed.

A better solution is to place the reticle in the front focal plane, or ahead of the power changing lens system. The movement of the erector system will, optically, have no effect on the point of aim here. So why don’t all scope manufacturers build them this way? The downside of this method is that Americans typically do not like reticles that grow in size when the power is turned up. There is no actual growth in the reticle size. As the magnification increases, so does the reticle along with the objects in the field of view. A one inch dot reticle will still be one inch, at any power, be it low or high. It is only the appearance that is altered. If the power is turned from 2x to 4x, or doubled, the size of the objective image is doubled, and so is the reticle along with it.

Since the front focal plane reticle is a superior aiming device but aesthetically not very popular, there is only that problem to overcome.

That problem has been solved by U.S. Optics engineers in the form of creating a series of front focal plane reticles that do not appear to change in apparent size as the power is changed. These reticles all have the same effect when sighting with them. U.S. Optics designs these reticles to not only diminish the negative idea of apparent change, but uses that concept to create an exclusively positive concept change. In other words, we use the single image concept of a reticle magnified to an almost unusable thick, heavy image at high power to create another entirely different and very usable, highly magnified reticle, without the normal disadvantages. We call this system of reticles our High-Low Imaging System, or High-Low Reticle. It is a completely different picture at high power, thus usage is dual purpose and increases the versatility of the scope tremendously.

With this system, the variable power scope no longer has any disadvantages, and many decidedly great advantages over a fixed power scope.
 

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With leupold (and most other scopes, SA not included) you have to be at a set magnification for the dots to be accurate, another reason why I generally prefer fixed power scopes.... I don't have to worry about my scope not being set "Exactly" at 10x, or 9x, or 16x or what ever its suppose to be at for that scope.

MEL
 

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I had a question about FFP mil-dot scopes. I thought that since FFP allows the mil-dot reticle to magnify with the variable power, you can still range with the dots?
 

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Leupold, at this time, only makes a FFP scope in the 3.5-10x40 Mark 4 M1 and M3 scopes but according to a post here not too long ago they will be making a 6.5-20 in FFP also. Basic rule of thumb is that if it doesn't say FFP then it's not FFP. Look at thier site and you will see. Thier other scopes usually have to be on the highest power setting, not always 10x, to mil correctly. So the 4.5-14x50 has to be on 14x to have the mildots subtend correctly. The problem with this is it can make miling or using the dots hard if you have heavy mirage or need a larger FOV like shooting movers and have to be on 20x to use the dots. You can do math and figure out where the proper half way point is but it becomes more complicated and in a stress environment it makes life harder on the shooter. If you do do this don;t trust the magnification numbers on the power ring. Spend some time at the range and figure it out yourself.

F2, with FFP you can use the mildots on any power and they will subtend correctly because the size of the reticle does change with the power setting.

Scope companies are seeing that some shooters want FFP and are starting to or have in development scopes in FFP. IOR and Leupold both do and Nightforce is in the works. Of course US Optics and S&B are also FFP but they are more expensive.
 

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I have started switching over to FFP scopes as well. If you are looking for a ffp Leupold, I would keep an eye out for one of the used Premier Reticle 3.5-10's that pop up every now and then. They are usually around 850-900 bucks.

I was interested in testing out the ones that Leupold are making, but the 8.5-25 is right around 1800 bucks new. There is no way that I would pay this much money for a Leupold. This is just a ridiculous price, and I would save the extra cash and go with a USO. The new IOR 3-18x42 is also a nice piece of glass, and will cost a few hundred less than the Leupold. Of course you have to wait until they bring more into the US, as there was only a limited run of the scopes done on a GB through SH. It cost about 1300, but will probably be a little more for regular runs.

John
 

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For the longest time when I was shopping around (and I'd never seen a FFP scope) I kept telling myself that I didn't really need FFP. I kinda liked the fact that Nightforce has the whole double halving thing going on. So if you get yourself a 5.5-22X you can use the MLR reticle at half mil points at 22X they become full mils per tick at 11X and they are 2 mil per tick at 5.5X. Heck if you spend the time to figure it all out you can even find a spot where it becomes a MOA reticle for you...

All in all once I got my hands on a FFP scope I was SOLD. When you have to zoom out cause you can't find the target fast enough at max power your reticle still works! Also having FFP allows you to get a scope with a higher top magnification because you don't have to worry about mirage problems as much. If I was going for a SFP scope there is no way I'd have gotten a scope with a 25 power max setting. Honestly I think thats why Bushnell put their correct subtension of the reticle at 12X on the 4200 elite. It also allows you to get a doubling and halving of the reticle but meh. Still the FFP is GOLDEN!

The other day a buddy of mine and I were out at the range and he was shooting his Thompson Contender in .223 at 200 yards. (its a .223 caliber pistol with a 10 inch barrel). Anyway he was asking me if I could see any holes in the paper. I didn't see any at all so I proceeded to laugh at him for shooting at 200 yards. Then I talked him into seeing a lone rock on the hillside behind the targets at about 275 yards (cause his true goal was to hit a gong at 285). I set my crosshairs on the rock and watched for the dirt to fly. It was 3 mils down. I then gave him a hold point by measuring 3 mils up from the 18" gong at 285 and proceeded to watch him put 5 shots on steel at 285 yards with a pistol. Next he shot his 50 cal pistol which had considerable more drop. Had I not had a FFP reticle there is no way I could have spotted these shots and got him onto target. Not that many scopes primary use are to act as a spotter but its nice when you're comfortable enough with a scope that you can instantly use it for measurement and to help call holds and shots for someone no matter how crazy they are! :)
 
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