Thread: scope sighting

Hi all,

About sighting in scopes.

I wonder if you have good advice regarding this. I have come across some very good info regarding sighting in at a shorter range, 50 meter, being preferred over longer range like 200 meters.
They have the following reasons:
1. 50 meter one has more confidence at right aiming.
2. trajectory is still going up and when sighting at 50 meters. This means between 100 and 200 meter (depending on the ammo) there is another 0. The bullet stays longer inside that famous 6-8 inch lethal area (picture a round long pipe).
3. Less wind and elevation factors error

disadvantage:
errors in sighting will become worse when shooting at longer distances due to the short range


What I am trying at the moment.:
sighting in at 50 meters.
CALCULATE the difference at 100 and 200 meter.
Dial the turret up to that CALCULATED elevation and check.

any thoughts?

I have used a 50 zero on occasion, as you say the point blank zero is slightly extended but not significantly so. For my 223 The so called zeros are at 50 and 125 but the trajectory only peaks at .3 inches above them at 75 yards which is margin of error stuff.
Parallax on a non adjustable scope introduces an error at that range as most scopes without it are set to be parallax free at 100. Changing scope height above bore has a significant effect also. Verification is always an excellent practice if you can do it. It is also quite instructive to shoot a tall target without ajusting the sight as you change range that way you can determine the actual drops and adjust any ballistic calculator values with confidence.

I've always liked sighting in at the longer of my expected shooting distance i.e. 200m for centrefire and 100m for rimfire. My personal preference is to aim lower at the shorter ranges, But I'm weird like that.

50m for .22 is ok, 200m for centrefire. Anything inside 250, line it up a shoot it. Also like to have an exact adjustment for 300m confirmed, often around 6 clicks up, 0.6 MRAD in a couple so easy to remember in a hurry.

Originally Posted by Taco

Hi all,

About sighting in scopes.

I wonder if you have good advice regarding this. I have come across some very good info regarding sighting in at a shorter range, 50 meter, being preferred over longer range like 200 meters.
They have the following reasons:
1. 50 meter one has more confidence at right aiming.
2. trajectory is still going up and when sighting at 50 meters. This means between 100 and 200 meter (depending on the ammo) there is another 0. The bullet stays longer inside that famous 6-8 inch lethal area (picture a round long pipe).
3. Less wind and elevation factors error

disadvantage:
errors in sighting will become worse when shooting at longer distances due to the short range


What I am trying at the moment.:
sighting in at 50 meters.
CALCULATE the difference at 100 and 200 meter.
Dial the turret up to that CALCULATED elevation and check.

any thoughts?

Work out the average range you will be shooting at: 50m, 100m ,150m. etc. Sight in for a zero at that range (using the ammo you will be hunting with!), then check the mid range in case a close shot presents itself. For deer, I sight in to have a bullet dead on at 200m, 50 millimetres high at 100m, then check the trajectory height at 50m.

Greetings all,
I do an initial sighting in at 60 metres after bore sighting, usually setting the sights for impact about 30 mm above point of aim. Once done the final zero is for up to 200 metres depending on the rifle. Most hunting rifles will tolerate a 200 metre zero without the mid range trajectory being excessive. The soft loads for my old soldiers require a shorter zero. If you are having trouble getting decent groups at 200 metres then the rifle or your marksmanship require attention, not necessarily in that order. The last thing that you want to be doing is dialling at under 200 metres. Zero your turrets at that range. One way of improving marksmanship is to practise with a .22 RF. I you are inclined to mash the trigger a .22 will tell you. Lastly make sure that you chronograph your ammo and sort your drop chart from that. I struggled with zeroing rifles when I was much younger. especially with open sights and later scopes of dubious quality. Take it slowly and you will be fine.
Regards Grandpamac.

For my .308 I mainly use it at the bush. Fiordland.
If sighting for 50 meters, it will be dead accurate between 0 and 150-200 meter (1 cm high on 75 meter, zero again on 125 meter).

For the 270 and 223 it might be better to go 100-200 zero, depending on what I expect to shoot at what range. anything above 450 yard I consider bit too far for my skill.

The range I can use (till 15.12.22 - thank you Jacinda :-( ) only has 50-200

Don't know if this helps, but I did a bit of research a couple of years ago on dialing a scope and found most balistics calculations are from the "far" zero.

Any scope dialers could help on this?

Well I used a 200m zero for decades on the 303 and it was never really good. Since most of my shots were between 50-150m (slips on North Island creeks and rivers) I always had to hold low. How low ? Always guessing a bit.

Once I changed to a hundred metre zero with a 7mm08 I could shoot from 30 to 130m with less than a centimetre departure from the crosshair and my success rate increased a lot. Beyond 150m I can dial, but it would also be OK to hold over. "Is it closer to 200m or 100m ?" "More like 300m than 200m ?" I'm not very good at range estimation, I know that from using a laser often, but even i can guess those.

There is a fallacy with the 6" tube idea: that you can shoot as far as the 6" (15cm) rise/drop "point blank range" by holding dead on.
Essentially, your rifle group size goes on top of that and your marksmanship error on top of that. (They are added by root-mean-squares, to be mathematical). For example, if your drop from point of aim at 250m were 4" (10cm) and your target were 8" across, then only the top half of your shots would land in the target. Who wants to accept a 50% hit probability when you've fired a good shot ?

Much more reasonable would be an acceptable range-drop error of 2" (5cm) at your max range, which should be only 200m if shooting without a range finder. If you do use a range finder and a simple drop chart, you can take almost all that source of error out and just concentrate on the hard stuff - hold, release, perhaps wind past 200m.

It is good to sight in at 25 or 50m because you will always hit an A4 paper so not waste any ammo. You just need to know the required point of impact for your 100m or 200m zero distance. It varies a little with your velocity and a lot with your scope height. Also you do need to check every now and then just where the shots actually pattern at 200m or 300m. That also gives you a reality check for how small an animal you can truly shoot under optimal range conditions. Don't rely on a calculated drop value when shooting at live animals. You should only shoot as far as you have verified on paper.

It is not good to use the full kill zone size, when calculating a "point blank range" .

I start off with calculating a 2" point blanc setup for my rifle. I use this tool: https://shooterscalculator.com/point...75&sh=1.5&ts=2

For a 300BLK it gives me 124 yard zero, minumum PBR of 8 yards, maximum of 143 yards.

Once zero'd on that I then use Strelok to give me drops at say 175, 200 and 250.

Went to shooting range. The person in charge told me to bore sight at 25. then shoot at 50, Then 100 and then 200. zero the thing at 200 he said, otherwise the drop after 200 meters is too high.

I use my 308 for bush, almost always between 30 meters and 200 meters. For this gun I would do 50 or 100 meter sighting. For the 270 and the 223 at 200 meter zero. Thought better listen the persons who have been hunting and shooting all their lives.

Bore site at 50yds,zero at a hundy,then leave 1.5 inchs high from zero.Good for 220yds point n shoot.308.