Gus and Greta are retired from farming and they will be traveling to hunt , so they both got rifles with sights.

They want to shoot out too 200 yards at game in 4-5 other states.

They only have access to 75 yards to practice.

is there some sort of extrapolation website that will them be dead nut on at 75 yards,
but then adjust their scope to 200 yard range, when they get there?

or is it not an option because they will be four different ammo's for four different critter's?


75 yards distance no clicks up
________ distance 2 clicks up
________ distance 3 clicks up
________ distance 4.5 clicks up
etc

My experience is that trying to do that is hit or miss.
Which for hunting is a no go for me. Find a range that has a rifle range that extends to 200yds. Pretty common.
Sight in at a 100yds. Should be and 1-1/2" high at that distance. Should be pretty much dead on at 50 and 200yd. for most hunting rifle calibers.

Huntind is all about confidence. If you have not confirmed consistent hits at the distance you plan to harvest animals at you very well might miss or worse yet, not make a good clean single kill shot.

A lot of variables there. One of the smart phone ballistic apps would help but will require input for each load. I use BulletDrop. There is a free version. I used the paid version (BulletDrop+) which I think is $2 or so. The paid version allows you to back up and save your data. This will at least tell you, on a given load zeroed at X distance, where it will impact at other distances. (in theory)

there are plenty of farm fields around here that are plenty long enough , but access to them is very limited.

I am wondering if they will just have to leave a day early and adjust everything , when they get there

C'mon, just say it. You don't know the flight ballistics of your our rifle.

If you know your muzzle velocity, sight over bore height, bullet type, and air density -- quality ballistics programs such as JBM can predict bullet flight with amazing accuracy.

Otherwise, go to the range and shoot targets at various distances.

In theory it’s certainly possible to zero a rifle at any distance even if one has access to only a shorter range. All that’s necessary is to develop a good trajectory table from a resource like the JBM ballistics calculator and precise, accurate load data, and then adjust the rifle sight so you’re hitting where the table says we should be at the distance we have available. E.g., if the table says for a 200 yard zero you’ll hit 1.6 inches high, mark a spot on the target and adjust your sights so you hit 1.6 inches high at 75 yards.

The problem I’ve discovered is that method usually doesn’t work all that well. In the first place the 75 yard group needs to be very small and based on a significant number of shots. Even then, when I go to my desired zero distance more often than not I don’t get the results I hoped for. Why? I usually don’t know. Zeroing at close range is better than not zeroing at all, but in my experience it’s just a start.

fritz if your comment is directed towards me. I will again say I am not a hole puncher. If I am going to harvest a live animal in the field under any variety of conditions. Yes I want to shoot my rifle with the bullet I intend to hunt with so that I know with confidence what will occur in that moment if it comes. So no, i do not care about what a computer program spits out.

quote:

Originally posted by old rugged cross:
fritz if your comment is directed towards me....

It isn't. Sounds like you've been to a rodeo or three.

IMO Gus and Gretta have no business shooting at live animals at 200 yards without having shot at inannimate targets at 200 yards.

Even the best charts and calculators are just educated guesses, they're aids, not gospel when so many variables are involved. Made 4x worse with 4 different bullets.

quote:

Originally posted by bendable:

or is it not an option because they will be four different ammo's for four different critter's?



etc

Four different ammo's for four different critters is a bad idea, especially if their time shooting at longer distance is limited.

There is very little good reason to do that.

If the firearm in question is, say, a 30-06. You could shoot a 220 grain bullet at an elk and a 125 grain bullet at a coyote. But there is a very good chance that the point of impact will be different. Enough so that it would be unethical to hunt with such a setup.


A very experienced shooters with a repeatable optic can track such variation and dial it in, but it is much easier and less prone to goof-up if you pick one ammo that has enough power to get the job done on everything.



They retired from farming but they don't have a friend or neighbor who is still farming that they can go shoot safely on private property?



In my experience, when I reach out to 200 yards when dialing in a new optic, I almost always wind up making some adjustments even if I felt I was really close on preliminary adjustments at 50.

You can get a rough sight-in at closer range, using a ballistic calculator or ballistic table to estimate your point of impact at the closer range for a zero at your desired longer range. (The more accurate and detailed the info you input, the closer this estimated zero will be.) But you'll still need to fine tune the zero at the actual further range when possible.

As for switching between different ammo types, you'll need to sight it in for one specific bullet load. Changing the bullet style/propellant/weight/etc. will cause your point of impact to move from your initial zero. Sometimes it's a small difference; sometimes it's a large difference.

For defensive purposes, sighting in with one load and then switching to a somewhat similar load will likely result in a zero that is still close enough for effective hits on man-sized targets at relatively close range. (Like sighting in with 55 grain M193 and then loading 55 grain Speer Gold Dots.) But for precise shots, such as when hunting at longer ranges, you'll have to sight it in with each new load.

They can certainly decide on a single load and then use a ballistics program like JBM to sight in their POI a certain number of inches over or under the POA at 75yds to be zero'd at whatever range they want.

In the Army we zero at 25m and qualify out to 300m. Not ideal, but it works for combat. 75yds is nearly 3x that distance so it would yield better results.

I also use a ballistics program and zero at 25 yards. Then I confirm zero at longer distances. Saves ammo, too, usually.
I often tape a small card to the stock showing the trajectory of the bullet at various yardages so I know the hold.
Not elegant, but it works

I will show them this information.

Gus got a 30-06 and she got a .243 winchester,both scoped, both bolt action