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Ok, I have a scope that the adjustment is 1/4" @ 100yds. But what is the adjustment for 200, 300, 400, etc yards? I was wondering if 200yds would be 1 click = 1/2", 300yds = 1", 400yds = 2"and so on.

I am looking forward to doing some shooting out to 400 yds and would love to know what a click would equal to in 100yd increments.

Thanks!!
 

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Just multiply the "1" in "1/4" by your distance in hundreds of yards. 300=3/4", 400=1 inch, etc.

But be advised that scope adjustments are not always exactly what they're claimed to be. I've got several where that "1/4 inch" turns out to be closer to a full inch at a hundred. Others are right on the money.
 

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Thanks Snake45!!! You know, they never say anything in documentation on the scope when you buy it. I guess they figure you will sight it in for just one range and leave it that way.
 

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yeah they don't tell you. I have seen scopes that are 1/4MOA, 1/2MOA, 1 MOA and who knows as there aren't any clicks. I hate them because you don't know what you did when you did it.
 

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You are talking about Minute of Angle or MOA.

At 100yds 1" equals 1 MOA, so 1/4 adjustments at 100yds will equal 1/4 inch

200yds 2" equals 1 MOA, so each 1/4 adjustment will equal 1/2 inch

300yds 3" is 1 MOA, so the 1/4 adjustment will equal .75

and 400yds 4" 1 MOA and 1/4 adjustment will be 1"

This tells you how much you will move the bullet strike for windage and elevation. A bullistics table will give you the basic drop for your round and that will get you in the ballpark. Ammo and barrel will figure into how into your adjustments but a good quality rifle in 308 or more is no problem at 400yds.

Hope this helps. It is one of those things you have to practice a little to get the hang of.
 

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If you plan on hunting to 400 yards you can zero for a point blank range. On internal adjustment scopes alot of them have aluminum parts and they won't take much adjustment day in and day out as the industry knows most guys sight them in and leave them alone.
Target shooters are a different animal and we are constantly cranking on windage and elevation taking it off.

The Sierra Program will let you calculate a more or less point blank range which keeps all your shots in a 10" circle from zero yards to whatever. You will have to zero at an odd range like 227 yards etc.

Personally I built a SHTF rifle in 7/08 and set back a 7MM target barrel and swamp cut the barrel. Bipod, pillar bed etc and mounted a Bausch & Lomb pistol scope forward of the receiver on the barrel. Depending on the weather I know it will hit a 2" dot at 300 yards first shot if I am reading the wind correctly.

For the shorter ranges I hold under where I want to hit and at 400 I hold over.

Takes about an hour of shooting and walking but I have targets I can set up for 100,200,300 and 400 in a close fan so all shots hit the backstop at 600 yards. I use the same type aiming points for all ranges which consist of dots from a target stamp set I found on internet that I can make 1" and 2" dots from.

I zero at 300 then go to 200 and 100 and shoot three shots each range and then go to 400 and shoot three shots. I then collect all four targets and measure the vertical line distance from the center of the dot to each shot hole, add all three and devide by three and record the hold under for 100/200 and the hold over for 400. I then make an adhesive lable with this data and stick to side of rifle and cover with packaging tape.

As a rule of thumb the hold over from 300 to 400 is about 12 inches.
 

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Getting ready to change out present scope on the Swamp Gun. I just got in two NC STAR 2-7X pistol scopes that were on sale for 42.00 including shipping. I mounted one of them on a Ruger Mk III and shot it yesterday and was pleasantly surprised how clear the optics are. The center of the duplex cross hairs are small and I could easily center a 2" dot at 100 yards and could see 22 cal holes at 100 yards on 7X setting.

The next game plan is to remove the 2X Bausch & Lomb from the Swamp Gun and replace it with the other NC Star and rezero for 300.

What will be interesting is if I can change the power and not have the zero change.

It is a longer scope than the NC Star 2X and the Bausch & Lomb pistol scopes by about 2".
 

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Hummer said:
yeah they don't tell you. I have seen scopes that are 1/4MOA, 1/2MOA, 1 MOA and who knows as there aren't any clicks.
With all the relatively "new" brands being imported from Romania, China, Singapore, etc., and individual components being sourced worldwide, who knows if they even made the conversion to yards/MOA . . . they may well be working on centimeters per click at 100 meters, and maybe they just changed the dial markings so they're "sort of" close to something we're used to working with.

I remember a time when we were getting some specialty zoom lenses made for us by a reputable company in Japan. Had some problems with barrel torque, so a couple of us visited the company. After an hour or so of discussions that seemed headed for an impasse, it hit me - we'd specified torque in inch-ounces, they converted to gram-centimeters. Thing is, they converted ounces to grams, but neglected to convert inches to centimeters, so everything was off by a factor of 2.54.

Oops. :oops:
 

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Your scope adjust is 1/4 MOA. That's 1/4" at 100 yds, 1/2" at 200 yds, 3/4" at 300 yds, 1" at 400 yds -- as noted above. But that just moves your point of aim. It doesn't compensate for bullet drop.

MOA "Minute Of Angle" is a straight line radian out as far as you want to go. So if you're 1" low at 400 yds, you need 1 click on the adjust knob.
 
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