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View Full Version : tutorial on scope power vs. distance vs. what you see?


high_revs
02-14-2007, 7:05 AM
am having a hard time going out there to the ranges to kindly ask people and talk to them about scope powers and ranges (work/school/prepping motorcycle for racing). is there a tutorial out there to help me understand how magnification relate to distance and what you see in the reticle at that distance? i see supersnipers are liked by folks here, but leopold is also and there is a big hike in price between both brands at times.

i seem to get more confused when others also comment on "how much do you want to see in the reticle." it's like, do you want a wide/panoramic lense for your camera vs. telephoto vs. normal.

my .223 build has been sitting for like 1 month after i finished it. :(

shark92651
02-14-2007, 8:02 AM
Don't wait, go shoot it with the iron sights first and get those zeroed in.

Here is a good tutorial on all the terminology of the scope:
http://www.optics4hunting.com/riflescope_faq.html

Basically the higher the power the less the field of view. The higher the objective lens size, the wider the field of view. You could get a scope with a variable zoom. For my first scope I got an inexspensive Accushot (Leapers) that is 4-16x56. This means the zoom factor can be selected from 4x up to 16x and it has a 56mm objective lens. It has mil-spec recticle for calculating distance to target and a side-mounted parallax adjustment. I am no expert, however, just sharing the little I know about it.

Mute
02-14-2007, 8:29 AM
See if this article answers some of your questions:

Practical LR Shooting: Optics (http://demigod.org/articles/practical-long-range-rifle-shooting-optics/).

high_revs
02-14-2007, 8:45 AM
kewl... thanks for the answers... more learning for me...

i was saving the iron sites for the 2nd build since i wanted something like eotech or aimpoint. just not sure what i'll do to my other 2 lowers, but i figure before i spend anymore money, use the dang thing that i have already. :)

alpha_romeo_XV
02-14-2007, 9:09 AM
Another aspect of scopes that I don't see discussed very much is the recticle. I've found the "blasticplex" type can be great for a gun that shoots far enough/accurately enough too warrant one. There are several mfr's that make them for NATO ammo, i.e. 5.56 or 7.62x51. I have a Springfield Armoury gen2 4-14x for 5.56 on a 24" bull barrel 1/8" twist A3 upper. Basically if you use a certain ammo and zero at 100m ( 69g HPBT at 2800 fps) the bullet follows a well known blastic curve (non-linear path) and the reticle is marked/calibrated every 100m out to 700m. I found this really works, no adding clicks, no calculating mil dots, guage your wind and use a range finder and you're right there in the black. The 7.62 is calibrated out to 1000m I think. Trijicon makes lower fixed power wide field scopes with blastic comp reticles that are used in combat by US according to their website.

shark92651
02-14-2007, 9:14 AM
Did you spell that correctly? I googled "blasticplex" and it comes up with nada.

alpha_romeo_XV
02-14-2007, 10:08 AM
Sorry about the spelling, hadn't had coffee yet. The key words to google could be BallisticPlex, also BDC (for bullet drop compensation). Here is one link to Burris - http://www.burrisoptics.com/reticles.html I took a quick look at Springfield's webpage and it looks like they no longer sell what I bought a couple of years ago.

shark92651
02-14-2007, 10:49 AM
I wonder if a table that has those values for mil-dot scope and various .223 ammo loads exists?

Edit:

Here is some info on range estimation with mil-dot scope: http://www.eabco.com/Reports/MildotRep01.htm

Here is some software that calculates range at each aiming point for your ammo: http://www.eabco.com/BallisticPlex.html

Mil-dot "slide rule": http://www.mildot.com/

There has got to be an Excel spreadsheet out there somewhere that has the same formulas in it.

alpha_romeo_XV
02-14-2007, 11:10 PM
Here is an image of the recticle in a Trijicon ACOG scope. I figure if you're going to use a scope why not use one with some "brains". The numbers are the 4, 6 and 800 yrd points ( odd dist's un-numbered). No help for windage but for elevation it's great. Red color is with illumination on. The horizontal marks assume an 18" distance for an average "target" shoulder to shoulder, so you have a range finding guage built in as well. I don't mind counting clicks in a match with no one shooting back at me, but in combat I think this would be faster.
http://i144.photobucket.com/albums/r182/wiskeypapa57/temp/trijACOG.jpg

jevonniespapi
02-15-2007, 1:03 AM
Good Info Here!

adamsreeftank
02-15-2007, 1:03 AM
Remember, any BDC reticle is designed for a certain round fired from a certain length and twist rate barrel. Even then, it will shift slightly based on elevation and air temp. They will almost never be exacly right past a few hundred yards, but give you a rough aiming point.

A traditional scope with target knobs will allow you to make adjustments for range and windage. A good quality 3-10 or 4-15 power scope is a great way to start.

On most of my scoped rifles, the scope cost around the same as the rifle. I have a few Leupolds, but I prefer Nightforce and Trijicon Acogs. If I had the money, I'd buy Schmidt and Bender or US Optics.

high_revs
02-16-2007, 2:03 PM
yeah.. good info. guess i know what i'll be reading over the weekend. :)

maxicon
02-16-2007, 3:39 PM
Here are a few more informative links:

http://snipercountry.com/Articles/MilDot_MOA.asp

http://snipercountry.com/Articles/RealTruthAboutMilDots.asp

http://www.shooterready.com/mildot.html