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Old May 30, 2009, 02:55 PM   #1
Fremmer
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Practical significant difference between low and medium rings?

I have a Remington 700 .308 hunting rifle. My shots are limited to 200 yards or less. I've always thought that you should automatically use low rings for a scope to keep that scope as close to the barrel as possible, because the lower the scope is to the bore, the more accurate your shots will be at longer distances. But like I said, I don't shoot at deer farther than 200 yards away.

I tried a medium ring set up on another rifle, and low and behold it was much more comfortable than my low ring set up. I have a long neck and fairly thin face, but whatever the cause, the cheek/stock & stock/shoulder feel was much better with medium rings.

So for a hunter who doesn't shoot at targets farther than 200 yards away, is there a significant accuracy advantage for low rings vrs. medium rings? Your opinions are much appreciated, I wish I knew more about this matter, but I just don't.
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Old May 30, 2009, 03:13 PM   #2
wogpotter
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None at all.

Where you will find a difference is if you shoot at a range very different from the one you sighted in at.

The sight looks in a dead streight line, almost parallel to & above the barrel. The bullet follows a curved path, first going up from below, passing thru the point of aim, rising up above it, & then dropping back. It passes the point of aim a second time coming down & then keeps dropping lower & lower till it hits something & stops.

If you sketch this out on paper it's a bit easier to follow, but bear with me.

The more offset the line of sight (from the scope) is the more difference there is in the difference between the bullet path & the view thru the scope. This means it starts out lower (comparitively) moves at a sharper angle, rises higher & faster, & drops back more sharply & further at the other end of the trajectory.

This is NOT a change in the bullet path, but in the relationship between the LOS & the PATH. This ends up being more off set at the same difference the higher the sight is mounted. At the point of zeroing they both match so there is no difference.
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Old May 30, 2009, 03:14 PM   #3
mikejonestkd
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In general it is better to have the scope as close to the bore as possible/ practical, but it has nothing to do with accuracy.

However, a rifle scope that is comfortably mounted at a height that works for you is more important than one that is a low as possible. Get the medium height rings and you'll be fine.

As an example : I spent part of thursday at the range with several firearms, including a shortened .22 bolt that my young son has. It was frustrating to get a proper cheek weld with the very low mounts for the scope and very short stock.

Comfort and easy of use is more important than what the experts say is " better "...
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Old May 30, 2009, 03:18 PM   #4
Fremmer
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That's what I understood to be the case. But may have to shoot at deer from 10 yards to (usually) 120 yards; I zero at 100, because about 95% of my shots are 75 yards or less, a few have occurred at a bit more than 100 yards. That 200 yard shot would be extremely rare (I would hesitate to take anything other than perfect broadside at that range from a stand w/a rest), but I would like to be ready to take it if necessary.
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Old May 30, 2009, 03:24 PM   #5
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Whether you should use low's or mediums depends on the scope, the ring manufacturer, and your rifles stock design. Some companies lows are a lot lower than others. Some stocks raise your head making it hard to see through your scope mounted in low rings.

Generally I like my scopes mounted as low as possible, but have to use mediums for some combinations. Use whatever it takes for you to mount the rifle and have the scope line up correctly with your eye
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Old May 30, 2009, 03:29 PM   #6
wogpotter
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At that kind of distance you'll never find any change at all.
Now if you went for a 350 yd shot (which I doubt you ever will, basrd on your post) then yes you'd be shooting quite a bit lower (comparitvely) with the higher rings using the setup you're thinking of & your zero. This applies to long range only, close up you'll be off by exactly the difference in height between the 2 ring types.
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Old June 1, 2009, 01:15 AM   #7
Major Dave (retired)
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Bullets never rise - they only fall

"... The bullet follows a curved path, first going up from below, passing thru the point of aim, rising up above it..."

NOT TRUE!!! A bullet never rises above the Line Of Bore.

Wogpotter - envision a straight line from the muzzle to the bullseye. This is called "Line Of Bore", or LOB. LOB is initially below Line Of Sight by the amount equal to the difference between the center of the bore and the center of the objective lens of the scope. These two lines are perfectly straight, with no curvature.

The bullet, NEVER RISES above the LOB, but immediately upon exiting the muzzle, begins to drop below the LOB, due to the pull of gravity. It always drops further and further below the LOB, as the distance from the bore increases and gravity pulls the bullet downward. As the bullet loses speed, the influence of gravity becomes greater, resulting in an ever increasing downward curve in the trajectory (flight path) of the bullet. This is referred to as "non-rigidity of the trajectory", Therefore, the greater the distance to the target, the steeper the trajectory.

So, how come the bullet crosses the Line of Sight twice? (It does do that, after all.)

The answer is that the scope is adjusted (internally) so that it looks downward at a steep enough angle to cross both the Line Of Bore, and the trajectory, initially at about 25 yards, and then converges to intersect the trajectory precisely at the range for which the weapon is zeroed. That's the definition of a "zero". Therefore, the trajectory of the bullet is below the Line of Sight to about 25 yards, above the Line Of Sight from about 25 yards, to the zero distance, below the Line Of Sight at any distance beyond the zero distance, and NEVER RISES above the Line Of Bore. The bullet is above the Line Of Sight, briefly, only because the Line Of Sight is angled downward, NOT because the bullet rises.

Sketch it out on a piece of paper. When properly sketched, Line Of Bore will be above the target, Line of Sight will start above Line Of Bore, go downward to cross both LOB and trajectory, and terminate at the target exactly where the trajectory terminates. The trajectory will begin at the muzzle, remain almost flat, but slightly below line of bore for about 2/3 rds the distance to the target, then "droop" the final 1/3 distance to the target, hitting it precisely in the center, exactly where the Line Of Sight terminates.


So, the OP asked if the accuracy would suffer if he used high rings to achieve a good cheek weld when he was shooting. The answer is that the accuracy is not affected. His scope, when zeroed, with the high rings, would simply be tilted (internally) further than it would be with low rings.
Using high rings, if the shooter tried a long shot (400 yards and beyond), he would need a greater amount of holdover than a zero using low rings.
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Last edited by Major Dave (retired); June 1, 2009 at 01:27 AM. Reason: Add info
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Old June 1, 2009, 10:09 AM   #8
waterhouse
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Quote:
"... The bullet follows a curved path, first going up from below, passing thru the point of aim, rising up above it..."

NOT TRUE!!! A bullet never rises above the Line Of Bore.
He said passing through the point of aim, which I take to mean the line of sight, not the line of bore. You are correct about the not rising above line of bore, as well as about your description of the bullet crossing the point of aim, but I still think wogpotter was correct in what he said.


Quote:
Wogpotter - envision a straight line from the muzzle to the bullseye. This is called "Line Of Bore", or LOB.
That isn't the way I envision a line of bore.

For example, let's say there is a target 700 yards away, one meter off the ground. I want to shoot it with my 45/70. Due to bullet drop, I have to point the rifle well above the target.

If I were to draw a straight line from the muzzle to the bullseye the line would go approximately from my shoulder height to the center of the bullseye. The bullet will start off above this line (what you define as LOB) and if I am going to hit the target it will never travel below this line.

I think line of bore is actually closer to imagining you have a laser boresighter. The perfectly straight line that a bullet would travel if there was no gravity or air resistance, represented by the laser, is the way I think of line of bore, but perhaps I have my terminology confused.

I think wogpotter had it correct. There is line of sight, which is a straight line from the sight to the target. The line of bore, labeled line of departure in the diagram, is the path the bullet would travel in a vacuum. The actual trajectory of the bullet rises to meet the line of sight and then falls to meet it again, typically at one early distance and then again at the distance the rifle is sighted in at.

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Last edited by waterhouse; June 1, 2009 at 10:15 AM.
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Old June 1, 2009, 10:55 AM   #9
Art Eatman
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Think "cheek weld". It's not an accuracy issue, particularly. The deal is to be looking right through the scope with your cheek firmly held against the stock. Guys who use high mounts and large-objective scopes often add a pad on the comb of the stock.
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Old June 1, 2009, 02:23 PM   #10
Major Dave (retired)
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Read what I wrote -

"When properly sketched, Line Of Bore will be above the target..."

The best way to see the line of bore is to put your rifle on a rest, remove the bolt, and look thru the barrel, centering your eye , sort of like using the barrel like a peep sight.
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Old June 1, 2009, 02:47 PM   #11
waterhouse
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I read what you wrote. I even quoted it.

You also wrote that what wogpotter said was "NOT TRUE!!!"

I included a diagram of how I believe things happen, which shows that what wogpotter said was true, namely that:

Quote:
"... The bullet follows a curved path, first going up from below, passing thru the point of aim, rising up above it..."
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Old June 1, 2009, 02:48 PM   #12
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I think a low profile is better for point blank shots.
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Old June 1, 2009, 06:40 PM   #13
wogpotter
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waterhouse.
Thank you for clarifying that while I was away, I appreciate it. The diagram is exactly what I was describing.

Major Dave (retired):
Quote:
"... The bullet follows a curved path, first going up from below, passing thru the point of aim, rising up above it..."

NOT TRUE!!! A bullet never rises above the Line Of Bore.
Please show me the phrase FROM ME, NOT YOU, where I say "Line Of Bore."
I used the phrase repeated above. The "point of aim" is the point aimed at, thus as seen thru the sighting device. You might also refer to it as the "Line Of Sight".

Last edited by Art Eatman; June 2, 2009 at 12:10 PM. Reason: Snark removed.
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