Built in adjustment

[enmainord]

I am not a military or le person, but i have been reading and learning here with great intrest for some time now.
Growing up in eastern Utah, we have hunted deer and elk at long ranges for years. I "sniped" my first coyote before i was 10 years old with a ruger 10/22 and fixed 4x scope. But we have always done it by "seat of your pants" type trial and error shooting, the boone and crocket reticle from leupold was big news in town when it came out.

I really like the science behind your methods as well as the "do it" as opposed to talk about it methodology. Very good stuff.

My question is this. I recently purchaced a couple of Leupold Mark 4, 6.5-20x50 LRT rifle scopes. These have 1/4 moa adjustment knobs. i notice alot of you guys are talking about using 20 moa bases in order to reach out there to those 900 yd. + ranges. With my scope mounted with 2 piece burris extreme tactical bases, with burris extreme tactical medium (1/2") rings mounted on a remington M700P and a M700ss 5r. With both rifles zeroed at 200 yds. I have 4 and 1/4 complete revolutions which if i am correct gives me 60 + MOA of adjustment ? correct ?
Is the difference the 50 mm objective, i notice the 40mm seems a little more popular with you guys. Anyway i am working my way out there to more extreme distances.
I hope to attend sniper/counter sniper this year.

Let me also take a second to thank those of you in service of our country in the military. I consider my self a pretty tough individual, I see news casts of you guys kissing your childeren and wives and turning around and getting on a plane to head into a war zone. I have 3 young daughters and as such, when I see this it kind of knocks the wind out of me.
In our current world of phoney hollywood type idiots, doing what you guys do is very extraordinay. Thank you for protecting my way of life. Thank you for leaving your children at home so that I can be at home with mine !

Anyway sorry for the length of this, any feedback on the built in adjustment question would definitly expidite my learning curve and save me a little .308 ammo.

[Cleck]

Originally Posted by enmainord

...With both rifles zeroed at 200 yds. I have 4 and 1/4 complete revolutions which if i am correct gives me 60 + MOA of adjustment ? correct ?...

Yes. However, why are you zeroed at 200yds? If you zero at 100yds with a .308, you will never need to adjust below "0" on your turret.

Originally Posted by enmainord

...Is the difference the 50 mm objective, i notice the 40mm seems a little more popular with you guys...

The reason some prefer the 40mm objective is that you can mount it lower on your rifle. It is not a standard by any means, just popular.

[RamZar]

Originally Posted by enmainord

I recently purchaced a couple of Leupold Mark 4, 6.5-20x50 LRT rifle scopes. These have 1/4 moa adjustment knobs. i notice alot of you guys are talking about using 20 moa bases in order to reach out there to those 900 yd. + ranges. With my scope mounted with 2 piece burris extreme tactical bases, with burris extreme tactical medium (1/2") rings mounted on a remington M700P and a M700ss 5r.

The Leupold Mark 4 6.5-20x50mm LR/T M1 Riflescope has 70-MOA each of windage and elevation adjustment with a 30mm main tube. You mentioned 1/2" rings!?

While at GPS Defense Sniper School I engaged a target at 1,200 yards using Federal .308 168 grain BTHP GMM ammo and it required 66 MOA. So, you can take yours at least that far.

There was a show on The History Channel called "Sniper: Inside the Crosshairs" and one of the segments was about Sergeant James Gilliland a United States Army sniper who currently holds the record for the longest sniper shot recorded for a .308 rifle. He had a confirmed kill on September 25, 2006, shooting into the fourth floor of a hospital (the coward insurgent was shooting from there) in the city of Ramadi, at 1,367 yards. He set his scope's turret for maximum elevation and then used his scope's reticle to hold over an additional 2 mils, or approximately 12 feet. Afterwards in an interview Gilliland said: "He was visible only from the waist up. It was a one in a million shot. I could probably shoot a whole box of ammunition and never hit him again."

[enmainord]

I guess the 200 yard zero is just something i've done because that is a little closer to what a shot while big game hunting is more likely to be. Is a 100 yard zero kind of the standard practice you teach ? Maybe a self taught bad habbit huh ?
The 1/2" rings i mentioned are the height of the burris mediums I am using. The scopes are the 30mm tube. Do you see much difference is the light gathering capabilities at dawn or dusk between the 40 and 50 mm objectives ?

[Cleck]

Not a bad habit, just curious as to the reason. Improper fundamentals are a bad habit.

You could zero your rifle at 314 yds and measure your dope in Dorito's Bag lengths if you want.. as long as it works for you.

Even if you feel that you are most likely to shoot at 200yds, I still am used to 100yds = "0" on your turret and 200yds being somewhere around 2 moa up. If you do this, your dope from 10 feet to 1000yds will all be above "0" on your turret. This is a must for folks with M3 knobs that have a zero stop built in.

[Lindy]

I have been using attoparsecs as an odd unit of measurement - but I really like Dorito bags!

Hunters using scopes with standard duplex reticles, i.e., no graduations in the reticle, could make effective use of zero ranges longer than 100 yards.

With scopes with graduated reticles, there is no reason to use an extended-range zero except where a rifle intended for extra-long-range shooting has a base with a significant slope, in order to extend the range to which the scope can be dialed.

An example is some of the Barrett M82A1s were delivered with 60 MOA bases with the intention of zeroing the scopes at 1000 yards, because the scopes put on them didn't have much internal adjustment.

Except for that, however, a shorter-range zero like 100 yards or meters is much easier to handle with a graduated reticle.

For example, my .308 with a scope having 5 mils of marks below the main crosshairs, can hit targets out to 600 yards simply by holding over from the 100 yard zero. I don't have to touch the elevation knob at all within that range.

In a counter-sniper engagement within that range with an opponent who has to dial elevation, I'll kill him while he's reaching for his elevation turret.

[enmainord]

Thanks boys, alot of damn solid common sense logic here. I like that.
I have 500 hundred rounds, my 700p, range finder, Sworovski's (spoting scope & range finder) and some steel targets loaded in my truck, I'am going to head to the desert and get in the middle of this tomorow.

[Cleck]

Originally Posted by enmainord

...Sworovski's (spoting scope & range finder)...

Must be nice.