- July 11, 2016 at 10:14 pm #28872redriverhunterParticipant
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I was wondering how much a scope that is mounted with out a level or anything, just looks to be good, compares to a scope that is mounted with the aids of levels. the purpose of the rifle will be hunting the longest shot could be 400 yards
- July 12, 2016 at 12:38 am #28876chutesnreloadsParticipant
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Suspect you’ll find holding the rifle exactly the same every shot will affect you more than how perfectly square the scope is mounted…….
- July 12, 2016 at 1:55 am #28877DanielParticipant
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If the scope is canted and the gun held plumb, sight adjustments will give both elevation and deflection changes when moving either reticle. That is to say, if the elevation turret is adjusted, a deflection change is made at the same time. How much depends upon the amount of cant.
- July 12, 2016 at 2:17 am #28878
Very intuitive question.
But the object of mounting a scope correctly is to get it parallel, not square.
The object is to make it so that the trajectory of the bullet followes the vertical leg of the duplex.
Basisally, you need the virtical leg of the scope to pass directly through the center of the bore.
Surprisingly, this is relatively easy to eyeball depending on the scope (Burris fullfield II is a classic example of a real bugger due to ifs suspended retical).
Anywho, most of the time the rails of the action are actually cut square to the threaded base mount holes on the top of the action, which means that you can actually use levels on the rails to judge squarness. However, don’t ever take it for granted, and always do a visual “sanity check” by backing off the scope a little and using your peripheral vision to determine if anything looks “off”.
Now that ive laid the ground rules, I will say that the Wheeler Engineering level system is handier than a three handled bottle of beer if the action was made correctly.
Typicslly, I like to place the magnetic level on the scope rail if at all possible, but if not, it’s often fairly close to stick it too the feed rails inside the action as it was intended to be used.
Larry Gibson can speak more to this with impressive personal experiences from his time spent in the field, but I feel confident that my advice will not contradict his.
I envy people out west who can shoot in the desert at night. Just a couple tracer rounds would tell you if your scope was perfect or not. Pull the trigger, and you could watch the bullet rise and fall in perfect alignment with the vertical leg of the scope.
Must be nice!!!!
- July 12, 2016 at 1:25 pm #28880GhostHawkParticipant
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Assemble scope in rings loose fit. (scope will move with pressure but does not slide on its own)
Shoulder rifle, while looking through scope turn until the vertical crosshairs is in the center of the base.
Tighten rings and recheck.
Now you can spend all the money you want on ring lapping systems, squaring leveling systems.
And if that is your choice that is fine.
Mine choice is to quickly get it “close” and close is close enough.
- July 12, 2016 at 2:40 pm #28881
It all comes down to how close you get the scope aligned to the trajectory. The flatter the trajectory, the less it matters.
Say you got the scope off by only 1 degree and you’re shooting a 45-70 @ 1500 FPS at 400 yards. Your bullet will drop roughly 143 inches at that range, so if you adjusted your scope for impact with the turrets or holdover, depending on the direction your scope is canted, you would be off with your windage at that range by 2.5 inches.
On the other hand, if you’re shooting a 270 @ 3050FPS at the same range, your bullet drop will only be 23 inches, and your error will only be .4 inches.
It’s a simple trig calculation where side B is your bullet drop, and angle A is your deviation in degrees from perpendicular. Solve for side A to determine your error. Doesn’t’ matter how far away the target is. All that matters is how far your bullet drops. Obviously, in a particular rifle, the further the target is from you, the more important this becomes, as your bullet drop increases the scope alignment error on target.
Does this apply to you?
Depends on how fast your rifle gets the bullet to the target at 400 yards, and how jacked up your scope is. Remember the figures above are for a deviation of only 1 degree which is pretty hard to eyeball. I often replace scopes for gents who mounted them by “using the Force” and they are off by as much as 10 degrees judging by my plumb line.
Check it out.
- July 12, 2016 at 2:52 pm #28882Butch WaxParticipant
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Laugh if you like but I’ve employed a simple 100 plus year old 9″ bullet level I was given by my grandfather long ago. Here’s the method I devised when I was a working gunsmith.
1. Place rifle with scope rings installed in a padded device to hold it vertically.
2. Remove top of rings and place a small level on the flats of the rings.
3. Level rifle in padded device.
4. Set scope on lowest setting (if possible ) and place it in rings and attach top of rings but not tight.
5. At a distance that can be seen, suspended a weighted string from ceiling with a pushpin in a manner so the string hangs in front of rifle.
6. Adjust scope until vertical of crosshairs and string are in line.
7. Tighten scope rings slowly and equally.
Now I know this sounds primitive as can be but the string hangs 100% vertical like a plumb bob. The weapon is, or should be, level in the cradle. Ain’t rocket science, just simple basis engineering. Takes about 10 minutes, including string alignment time.
So, that’s the way I set up countless number of customers when I worked on their weapons. That mounting technique, and a fast boresighting cost them a minor fee, but they were always on paper and the rifle with scope were inline when they went to zero the weapon.
And ya’ll got this for free!:)
- July 12, 2016 at 4:51 pm #28883
Doesn’t sound primitive to me BW. A plumb line is the only instrument that can square up your vertical leg properly.
- July 13, 2016 at 2:18 pm #28889uber7mmParticipant
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Brilliant! Plumb bobs are cheap and idiot proof (for the most part).
- July 13, 2016 at 5:31 pm #28894
All I did for a wind bucking plumb line is pour a 2lb cannon ball sinker and tied some parachute cord to it. Strung it up at 50 yards and spray painted it white.
I use the line for the virtical leg, and the round lead ball as a point to bore sight to.
I keep a lead sled outside the shop to put the rifle in.
- July 13, 2016 at 8:47 pm #28895sundogParticipant
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What GS said. The WE Level-level-level is good, as is a plumb line bore sight.
- July 14, 2016 at 1:27 am #28898redriverhunterParticipant
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thanks for all who have posted, I have searched the net and found a lot of this and that but nothing as straight forwards as this thanks rrh
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