Scope has no more adjustment

[sub.sonic]

Hey guys, I installed a NF Benchrest scope with a 20 MOA base on my rifle, I have the elevation adjusted all the way down to the bottom and bullet impact is 27 inches above point of aim at 200 yards. Trying to zero rifle at 200 yards to be able to shoot out to 1000 yards. Does anyone have any suggections as to how I can eliminate this problem or to compensate of it?

 

[fivering]

You obviously do not need the 20 min bases. Take them off and put a standard base on. QED.

 

[Taildrag15X]

You'll never make it to 1000 with a flat base, run your ballistics and go from there. The Nightforce BR's lack elevation adjustment that some other (US) scopes have.

 

[CJ6]

with a 27" high zero @ 200 you should be close to a 1000yd zero (depending on bullet BC and Velocity)

 

[pdog06]

Is this a new gun or did you have another base/scope setup on it before? What rings do you have?

27" high @200 seems really high no matter what base you got. Just curious if there could be something else wrong other than the scope.

 

[cmillard]

you must have one of the higher magnification night force models--they have less internal adjustment.

 

[CJ6]

The 20 MOA base changed your bullet impact 40 MOA @ 200 yds. If your scope has for example 40 MOA TOTAL adj. and the crosshair was centered (for 1/2 up 1/2 down) the 20 MOA base just wiped out all your adjustment available @ 200yds. Tapered bases are meant to get you beyond your scopes adj range ,The price you pay is CLOSE RANGE ADJUSTMENTS. That's just the nature of the beast.

 

[sub.sonic]

I am shooting a Savage single shot target action with a Shilen 26" ss barrel in 223 REM with a 1:8 twist, on a bedded factory F-Class stock, the base is a EGW 1 peice 3" ext 20 MOA, the rings are Burris Xtreme Tact and the scope is a NF BR 12-42X56 NP-2DD. My load is Nosler cus comp 80gr (B.C. .415) pushed with 25gr Varget and WSR Primers. A fellow shooter with the same barrel and recipe chronographed his around 2750 fps. If I replace the 20 MOA base with a standard base, do you like I can get enough elevation out of this scope to go to 1000 yards?

 

[CJ6]

With that bullet/vel combo you need to be 75.74" HIGH (bullet impact)@ 200yds. Thats useing 80gr Nos.,2750 fps,59 deg.,78% RH, 1200ft ele,29.85 Bar press, scope height of 2.05..... YMMV

 

[sub.sonic]

CJ6, if I read this correctly, you're saying in order for me to be on target at 1000 yards my bullet should impact my target 75.74" above my point of aim at 200 yards! Please understand I am a novice shooter, about 3 years into the sport and have never shot beyond 200 yards. The scope I was using before the NF was a BSA. A friend and fellow shooter convienced me to expand into the 1000 yard game and this coming weekend will be my first time.

 

[zullo74]

I believe CJ6 must have read the drop chart incorrectly. I used Quick Target software and you need to impact about 35 inches (33 MOA) high at 200 yards to be on target at 1000 yards. Be advised that your load is only just supersonic at 1000 yards and is already a hot load (1180 FPS).

 

[sub.sonic]

zullo74, thanks for your input, so in your opinion with my scope already being 27" above POA I should be close to 800 yards and should only have to come up about 60 clicks to be on paper at 1000 yards.

 

[zullo74]

On paper it would appear that way. The bigger question is why is it shooting so high at 200 yards? The barrel could be bent, or not true to the receiver. I have 20 MOA bases and have NEVER had one shoot as high as yours at 200 yards. I have always been able to zero at 200 yards and then come up the required amount to shoot 600 yards or 1000 yards.

 

[CJ6]

The numbers from RCBS load are as follows..Range in yds bullet Height in inches......0yds --2.05, 100yds +39.54", 200 yds + 75.74", 300yds 105.63" , 400yds 128.04", 500yds 141.58", 600yds 144.50", 700yds 134.67", 800yds 109.47" 900yds 65.77", 1000yds 0"..This is above line of sight.

 

[zullo74]

CJ6,

Those LOS numbers are USELESS for setting up a scope. Bullets do not fly in a straight line (LOS). That's why sub.sonic was confused.

 

[CJ6]

The effect of the 20 MOA base has RAISED the bore centerline 40 MOA @ 200yds compaired to the SIGHT line.

 

[CJ6]

If he wants to be Zeroed @ 1000 that is the bullets path . Now subtract 20MOA for each 100yds due to the base.

 

[anyrange]

Sub Sonic,
If you are 27 inches high at 200 yards you should be zeroed at about 590 yards and need about 24 moa more for 1000 yards.

You need about 39 MOA to go from 100 to 1000 yards on a warm day. Since you are about 14 moa high at at 200 yd with the 20 moa base, you switched to a standard base you would use up about the first 6 to 10 moa on your scope for zeroing. I think your scope has around 45 moa of total elevation so you might not have enough have enough elevation for 1000 yards with the standard base. The way it is you are good for a very cold day out to 1100 yards.

 

[sub.sonic]

Thanks gentlemen for all your input. I held a metal straight edge on the barrel at three different locations with a flashlight behind it and could not se any light. The only thing I did different was to remove a standard base and a cheap 8-32X46 BSA scope and replace it with the EGW base, Burris rings and NF scope, a Cadilac setup. All screws were cleaned, loctite ablied and torqued to specs on the base. The rings were installed, lapped and aligned before installing the scope. Is it possible that the base is more than 20 MOA, manufacturers defect? Or maybe the rings are also 20 MOA?

 

[jesilva]

Think maybe the base is reversed giving you 20 MOA negative elevation instead of 20 MOA positive. In essence maybe the front of the scope was raised instead of being lowered.