I've been a shooter for quite a while, but must confess a total ignorance on scopes.  I just purchased an AR-10 and understand power/magnification/obj lens/1st focal/2nd focal, but beyond that, I'm lost.  I'm not a "wannabe tactical" guy, but find range-finding scopes fascinating.  I shoot paper at known distances at the range.  However, I want to learn how to use a scope with Mill dot/MOA hash marks to be able to shoot at 100, 200,300 and 400 yds interchangeably without scope adjustments.  I know range-finding scopes are used by military and hunters when the target height is known, however, is it reasonable to use for bullet drop/wind?  Or am I showing my ignorance?  What would be a reasonable scope to use that does NOT need to have military requirements or nonsense that an average shooter like myself doesn't need?  Please be blunt---I need it; and thanks--Steve

"Mill dot/MOA hash"  those are just two different ways to represent the meaning of the markings on your reticle and how much each 'click' of your scope adjustment knobs will change the POA.

Basically, 1 Mil = about 4" at 100 meters,  and 1 MOA = about 1" at 100 yards.  Probably most shooter/hunters are more familiar with thinking in terms of MOA. It's my preference anyway and something I'm used to working with on sever different rifles.

There are ways to determine distance to target with your reticle but it depends on whether it is a FFP or SFP scope. If you're more into shooting targets at range distances you might be more happy with like a 2 - 9 power scope.  The kind of scope you want really depends on what you're gonna use the rifle for and what kind of reicle you like to work with or whether you like to use holdovers vs. a scope adjustment to to compensate for bullet drop.

First advice…. Buy a GOOD scope.   Spend the money.

For known distance, sfp vs ffp doesn’t matter much.

If you want a scope that you don’t have to dial for distance and Wind, some type of Christmas tree reticle or Horus reticle is a must.

Mil vs moa is personal preference, although I prefer mil bc the math is much easier.

I cannot stress this enough, buy a good scope.   I learned this the hard way.   I’d much rather have a $300 rifle with $2000 scope than a $2000 rifle with a $300 scope.

Like the prior poster wrote, a scope with a Christmas tree or Horus type reticle will allow you to shoot at different distances without having to dial for drop or windage.  

I understand the principle of using one's scope for range finding, and although that might work fairly well for short to mid range, I just can't see how that's accurate enough for successful long range shots.  I think you'd be much better served with a laser range finder, but that's just my opinion.  

I know it's been said, but buy as much scope as you can afford.  I bought my long range gun for just a hair under a grand.  I spent $2400 for the scope (and another $200 on rings).

Some optics with BDC reticles include a "ranging feature" ... basically either a separate / secondary reticle or component of the main reticle that is caliberated to be around 19" at 100, 200, 300, 400, etc yards.

Why 19"?

It is the approximate width of a man's chest/shoulders.

Find which "hash mark" fits the man across the chest and read the number next to the line.  This is your range.

Use your main reticle "BDC" hash with corresponding number.

Breath, hold, squeeze through trigger pull.

If the 19" ranging feature doesn't work for you ... just buy a laser range finder.

Created that graphic to help you out.  Enjoy your range time.

Ranging / Wind Dope Exercise ...

You use your range-finding reticle on a 19" wide target to determine the distance to be 300 yards, and estimate a 10mph full value wind traveling from your right side to your left side ...



This is the resultant aiming point in your reticle ...

OP, one important 'ingredient' that is missing from this discussion so far - know your cartridge's velocity out of of your rifle.  308 pills' velocities varies greatly due to bullet weight and loading, so a chrono graphed velocity out of your rifle is important to calculate bullet trajectory before you can use the scope's Mildot or MOA marks.  The difference between a 16" and 20" barrel velocity for the same cartridge/loading can be more than 1 moa.  Know your rifle's ballistic is utmost important regardless of optic.

Regarding windage hold, the ballistic calculator will tell you that, again based on your cartridge's velocity & mass.  For 308 bullets, windage hold for 5 mph cross wind is practically nothing up to 400 yds but for a 55gr 556, that can be a miss on a 12" plate at 400 yds.

If you know your dope sheet and practice, yes, having the extra aiming indicators will let you adjust range wihtout fiddling with your knobs.

The key though is practice and really determining where you are hitting at known distances based on the dots, etc.

I usually have to let my own eyes pick the scope by that I mean your specific eyes and any problems they have may render a scope that would be great for someone else a poor choice for you.  I am very near sighted with lots of astigmatism.  I have gotten along well with Leupold/Steiner and Meopta but a friend of mine says they are more than he needs....he has way better eyes than me.  HTH.

Set a budget. Find the best scope within that budget based on reviews coupled with in person testing (if possible).

400 yds? 1-8 should be plenty.

just go on the E.E. pick up a Vortex PST ffp in either moa or mil
whichever you want to learn , you will still have a life time warranty
with even a gen 1 pst .. there's a couple 4X16 on there now .. and if
you want to upgrade to better glass you should be able to sale at your
purchase price as they carry a 4 to 550 price range every day of the week .

TS2

Look at Meopta's Optika5 2-10x42 PA or 3-15x44 with Z-Plus reticle. The Z-Plus is an MOA reticle and you can dial in the drops using Strelok Pro and your ballistic data. It is a great app and as long as you enter good data, very accurate.

Good job illustrating with this reticle.

BTW, this is the Vortex Razor Gen3 1-10x scope.  It has 2 reticle options.  One is an MOA based BDC (Minute-of-Angle, Bullet Drop Compensating).  And the other is MRad (milliradian. Milliradian = mil. An MRAD reticle is marked out in mils and fractions of mils to allow you to estimate the range).