Side mounted scope not centerd

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Just sighted in a side mounted scope. On a Savage 340. Its over to the right about 1/4" Its grouping nicely at about 3 inches above bulls eye at 100 yds. Perfect. Is that going to carry on out to 200 yards or is it going to be off sideways more to the right? I'll try when I can but curious if you have experience with a scope not lined up with the barrel
 
Yes. It will be off at 200, by the same amount that the scope itself is off at 0.

Think about it as two parallel lines if they're in line with each other, and two lines that cross if they're not. If you have it zeroed at 100 that is where the two lines intersect. Anything shorter will be off in one direction, anything longer will be off in the other.


I see two options:
1) sight it out as far as you'll use it. Then you're always bang on, or no less than 1/4" off.

2) sight it straight. Have POA 1/4" to the left of POI at all distances.
 
Thats what I was thinking. Any experience with how much
If your scope is 1/4" left of the barrel at 0, sighted in for 100yds, it should be 1/4" right at 200, 1/2" at 300, 3/4" at 400.

Realistically it's a tiny amount. If it's a 30-30 I wouldn't even think about it. If it's a 222 and you're trying to hit a varmint at 400 it MIGHT matter. But even then, it's only 3/4"...
 
There's really no reason at all that the optic needs to be precisely vertical overtop of the bore, i.e. this is the same mechanic at play when your scope is canted in the rings such that the reticle is level to the earth while the whole the rifle is canted (a very common setup). It's makes no measurable difference to point of impact (probably less than bullet diameter, on target). Think of WWII sniper setups where the scopes were side mounted and deliberately NOT over top of the bore line while the rifle was held vertically.

Scroll down a bit at this link for some good diagrams of what is happening.

https://www.snipershide.com/shooting/threads/scope-cant-question-and-thoughts.7126499/

Bottom line is that your setup is fine.
 
Duh. Just got it lol. Canting the rifle. Shouldering it not perfectly level. Got it:)
And if you wanted to test it (it would have to be a a significant range, maybe 500m?), you could group it as-is, then rotate your scope counterclockwise in the rings to bring the bore back under the crosshairs (with the rifle canted, now, to the right). There will be no difference in POI that you could measure.

The reticle NEEDS to be level when you zero, and when you squeeze the trigger. The orientation of the rifle relative to the scope makes no meaningful difference.
 
Nice, I love your rifle! back in the 70's and 80's .222s were all the rage, .223 was just comining in and starting to displace the .222 in the early 80s. The .222 displaced the .22 mag for fox hunting in our area, then the .223 displaced the .222. Interestingly, each was an advancement over the previous round. Today, most new cartridges don't do a whole lot new. LOL. The .222 is noted for it's accuracy though.
 
Savage/Stevens 325/340 rifles were offered in .22Hornet. .222, .223, .225 and .30-30. Any others?

A quarter inch offset is negligible. It will disappear in the group.
If offset is dramatic, like a M94 with side mounted scope, there are two options. If the scope is offset 1", zero so the group is offset by that amount. That is, the axis of the bore and the axis of the barrel are parallel. If the rifle is zeroed so that point of aim and point of impact exactly coincide, that will be true for only the zero range. Beyond that, the POI and POA will diverge in ever increasing amounts.
 
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