Issue with sighting in new rifle

[Owen]

hadmanysons,

What distances are you actually expecting to be shooting at? 20MOA bases are for very long range shooting. If this is a hunting rifle, for say out to 2-300 yards, 0MOA bases will work fine for you.

 

[JDGray]

hadmanysons,
Rems are known for recievers that aren't perfectly flat. When you tightened your base, did you notice it being pulled down as you tightened it? If the recievers off, the base will conform to the reciever, and may be why your POI changed when moving the scope and rings back. Its always a good idea to bed the base, to eliminate any warping as you tighten. If you start by tightening the second bolt from the front, look for a gap under the rear of the base, and if theres one, you need to bed the base. Good luck, let us know how it goes

1858,

No appology needed, but believe me, I couldn't figure that one out for the life of me I have never played with canted bases, so I couldn't say for sure.

 

[hadmanysons]

hadmanysons,

What distances are you actually expecting to be shooting at? 20MOA bases are for very long range shooting. If this is a hunting rifle, for say out to 2-300 yards, 0MOA bases will work fine for you.

100 yard sight-in. As long as it is on target there, I don't care if I only have 1MOA travel above that, cause it's all down hill from there

Rems are known for recievers that aren't perfectly flat. When you tightened your base, did you notice it being pulled down as you tightened it? If the recievers off, the base will conform to the reciever, and may be why your POI changed when moving the scope and rings back. Its always a good idea to bed the base, to eliminate any warping as you tighten. If you start by tightening the second bolt from the front, look for a gap under the rear of the base, and if theres one, you need to bed the base. Good luck, let us know how it goes

I didn't notice any pulling but that doesn't mean there wasn't any. Not an appetizing thought as i've loc-tited that sucker down. We'll see, gonna try and hit the range thursday

 

[hadmanysons]

Well, problem solved. Guess the scope was A: loose and B: to far forward. Shot like a dream today. Really good day at the range. Thanks for everyone's help in getting this figured out. Special thanks 1858, JDGray, and Maverick223 for all your guys' help.

Here some shoots from today.

The first load I tried out, came out to .603 MOA at 100yds



The second load I tried, comes out to .361 MOA if you don't count those two "called fliers" 1.369 MOA if you don't



The second load again, little more consistent .604 MOA here, no fliers



And then I took some shots at 200 yds for fun, using Federal American Eagle 150gr FMJ BT, .204 MOA if you don't count the "called fliers" but 1.104 in reality


Thanks again guys.

 

[Maverick223]

Don't know how much help I was, but glad you got the problem solved. Doesn't look like it is shooting to bad either.

 

[JDGray]

Glad your on paper, and shooting great groups! Wish my Savage 10FP would shoot that American Eagle that well! Gots 80rds left, that I use for foulers

 

[Ohio Gun Guy]

Can you guys re-tell how this work in "idiot" speak, I'm very interested but not following your information.

 

[Maverick223]

Can you guys re-tell how this work in "idiot" speak, I'm very interested but not following your information.

I am not fluent in "idiot" ...but I think the mounts/rings were just a bit loose. Moving the scope up and down the rail should have no impact as long as everything was machined correctly.

 

[hadmanysons]

I don't think the "loose-ness" of the scope was it. It was the "Sight height over bore" that did it. If everything was on the same plane it could have probably been attributed to a loose scope but in this case we are talking about many inches over a short distance of scope travel based on a 20 MOA cant. If you were pull up a ballistics calculator that compensates for "Sight height over bore" and change that from 1.2 inches to 2.4 inches you would see a drastic change in POI at 100 yards and then some on even further ranges because of the change in "relative" perspective with respect to the scope's height over the bore.

 

[Maverick223]

If you were pull up a ballistics calculator that compensates for "Sight height over bore" and change that from 1.2 inches to 2.4 inches you would see a drastic change in POI at 100 yards and then some on even further ranges because of the change in "relative" perspective with respect to the scope's height over the bore.

That is a constant...1.2in. above the bore will be 1.2in. at 100...200...400...800...or 1600yds...and yes I ran the numbers to verify. That said, I am glad you found the problem, no matter the cause.

 

[hadmanysons]

That is a constant...1.2in. above the bore will be 1.2in. at 100...200...400...800...or 1600yds...and yes I ran the numbers to verify. That said, I am glad you found the problem, no matter the cause.

True, it is constant. But take the numbers for 1.2 and compare them to 2 and you will see a difference. A lot as the distance changes because the available Field of View is changing.

This set of data is based on a 168gr bullet, shot at 2650 fps, sighted in at 100yd at 1.2 inches above the bore perspective
Range Drop
0 -1.20
100 0.00
200 -4.56
300 -15.82
400 -34.93
500 -63.29
600 -102.60
700 -154.91
800 -222.70
900 -308.89
1000 -416.99

Now the same set of input data but based on sights that are set 2 inches above the bore
Range Drop
0 -2.00
100 -0.01
200 -3.77
300 -14.24
400 -32.56
500 -60.13
600 -98.64
700 -150.16
800 -217.16
900 -302.56
1000 -409.88

At 200yds that's already almost 1 inch of difference. I won't begin to speculate the change in sight height of my rifle before I moved it back but I will speculate that with that change and the combination of the looseness of the scope could account for an almost 10in difference at 100yds.

Just my opinion