Saw a reference to this article while down at the Auto Parts store this morning getting some parts to retro fit and A/C system from R 12 to R 134a.....

Interesting...to say the least... and very logical

the link: http://www.americanhunter.org/articles/26-yard-hunting-zero

the article:

uch has been written on the ideal distance to zero a hunting rifle. There is no best sight-in range for everyone, because the range at which hunters expect to shoot their quarry differs considerably. There is one technique, however, that should allow you to hold your crosshairs on the vitals of deer-sized game and keep the bullet inside the vital zone out to 280 yards�and Jeff Johnston's ready to share it with you.

By Jeff Johnston (RSS)

February 04, 2014

Much has been written on the ideal distance to zero a hunting rifle. There is no best sight-in range for everyone, because the range at which hunters expect to shoot their quarry differs considerably. For example, if you hunt exclusively from a ridge top that overlooks a food source that is 150 yards away, you should zero for that distance. But if you hunt various terrain that offers both short- and long-range shots, here�s a technique that�ll allow you to hold the crosshairs on the vitals of deer-sized game or larger and keep your bullet inside the vital zone out to 280 yards, give or take a few yards depending on your caliber. It�s called point-blank range, and to maximize it you should alter your sight-in range for a particular load, rather than letting your traditional sight-in distance dictate your rifle�s zero.

Point blank range defined is the range of distances at which you can hold your rifle on the bullseye and never fall in or out of your target�s kill zone. The point blank range for a deer, for example, is generally regarded as six inches. In other words, if you hold dead center on the vitals, your bullet can be 3 inches high or 3 inches low before it slips out of the vital zone. An elk�s vital zone is larger of course�we�ll say 8 inches. But I like to stay with the 6-inch rule of thumb because is allows for some shooter error, an occurrence that you�d be naive to assume doesn�t happen while in field positions shooting at wild game.

So many hunters zero their rifles at 100 yards that it�s almost become standard practice. But the following examples will illustrate why that�s not a great zero for a rifleman who wishes to be able to take shots quickly, without calculating, from point blank to nearly 300 yards.

As an example, let�s use a very common hunting round, a .270 Win., loaded by Remington with a 130-grain Premier Accutip boattail bullet that has a .447 Ballistic Coefficient (BC). It�s got a muzzle velocity of 3,060 fps. Ballistically, it falls in line with a whole class of moderately fast calibers. The scope (line of sight) is mounted 1.5 inches over the middle of the bore. Zeroed at 100 yards, the bullet will impact .76 inches low at 25 yards (this is just fine for hunters), and will be 2.98 inches low at 203 yards. But after 203 yards it falls below the 6-inch vital zone. (That�s missing the 6-inch circle, 3 inches below the center, or point of aim.) At 250 yards, it will impact 6 inches below the point of aim, (three inches out of the vital zone.) So, with a 100-yard zero, a hunter can simply aim at a buck and expect to hit it in the vitals anywhere from 0 to 203 yards.

Other riflemen who routinely hunt areas where shots of 300 yards or more aren�t uncommon sometimes opt for a 200-yard zero. This places that same .270 bullet 0.4 inches low at 25 yards, 1.41 inches high at 100 yards, 2.51 inches low at 250 yards and finally slips below the 6 inch vital zone at 257 yards. So with a 200 yard zero, a hunter can hold dead on from 0 to 257 yards and kill the animal, assuming he does his part and fires an error-free shot. As you can see, the 200-yard zero is very effective, and if your target range will accommodate it, great. But many hunters don�t have the luxury of zeroing at 200 yards. No worry, there�s a better zero anyway.

Using ballistic software downloaded from Remington.com, I manipulated the zero range input data until it was optimized for the greatest point-blank range. (Another great website for finding maximum point-blank range is ShootersCalculator.com.) I found that by zeroing my rifle in at 26 yards, the .270 will deliver its bullet 2.81 inches high at 100 yards, 2.80 inches high at 200 yards and 2.12 inches high at 250 yards before finally falling out of the 6-inch vital zone at 310 yards. This means that with a 26 yard zero, I can hold dead-center of a deer�s vitals and kill it cleanly from 0 to 310 yards without adjusting my hold.

Of course, this is an on-paper estimate, and until you actually shoot your rifle at those distances, you can�t be sure, but I�ve found it to be pretty close. For most rifles, a 25- to 28-yard zero (depending on the caliber�s velocity and bullet�s BC) will maximize its point blank range. My technique for shooting is to zero at 26 yards (if using the .270 noted above), then shade slightly low (an inch or two) when shooting at 100 yards, and hold slightly high at 300. This increases my margin of shooting error, while allowing me to not have to calculate or hold off the animal at 300 yards. I simply see the animal, range it and shoot�out to 310 yards. Any further than that, I can either use my scope ballistic reticle, or know my caliber�s ballistic data and hold over appropriately.

If you choose to employ this 26-yard technique, beware that when zeroing at close range, you must strive for perfection. Place a dime-sized spot on the target and do not deem your rifle �good� until the bullet actually punches that dime on a consistent basis. If you are an inch high or low, or to the left or right, you will be way off at longer range, and it defeats the whole purpose of zeroing in at such a specific range. If you can�t hit the dime at 26 yards, it indicates that your rifle (and/or you) probably isn�t accurate enough to be shooting at long range anyway, because if your rifle is grouping 1-inch at 25 yards, for example, it will likely be 4 inches off at 100 yards and well off the paper at 300. But with the technique mentioned above, you can simply aim for an animal�s vitals out to 300 yards and concentrate on a smooth trigger pull.

The Data

.270 Win. at 100 Yards:

This graph illustrates that with a 100-yard zero, your bullet is on at 100 yards, then starts falling rapidly, and is 3 inches below the point-of-hold at approximately 200 yards.

.270 Win. at 26 Yards:

The graph shows that your .270 Win. bullet, when zeroed at 26 yards, angles above the line-of-sight 2.81 inches at 200 yards, crosses the line of sight (zero) again at approximately 275 yards, before falling beyond 3 inches low at 310 yards. Therefore, with a 26-yard zero, you can hold on the target and expect to hit a 6-inch vital zone from 0 to 310 yards.

Tags: 26 yard hunting zero, hunting, hunting tips, hunting zero, jeff johnston, shooting, shooting tips, zeroing in your rifle

When I was 13, my friend's dad would take us to zero all of our rifles before we deer hunted.

He did it at 25 yards.

That was 37 years ago

Been done that way in the military for years.

I sighted in a 338 WM with 210 NP at 25 yards this weekend. Took the target out to 100 and was 3" high. Should be about 3" low at 280 yards. Headed to So Africa with it next week.

3" hit at a 100. Used it for 32 years. Never failed.

Good article. Been doing more or less the same for years.

Somehow I think that someone who shoots at 25 yard targets might be less effective at 200+ yards. MOA is exponential going from 25 to 300 yards.

Funny, I use to do the same thing and learned that as a kid, being around military family and family members... reading rag mags, got away from it...

For years I have sighted mine so that the bullet never goes more than 3" above the line of sight at any range.

3" high at 100 is my standard sight in for a deer / elk rifle. Just about exactly the same as above, with less potential (4 times less) for seemingly minor adjustment errors.

Thanks, Seafire. Nice article, although old stuff to some old hunting guys - including me.

Now, how far are you going with "replacement" parts for the old AC in converting from R12 to r 134a? Are you replacing "O" rings, dryer, comp oil, and ???

After years of fretting, I now simply drain the oil and flush, install Ester 100 oil which is compatible with both refrigerants, evac and run in the R134a. I have two old systems running that way - no issues so far. Maybe I'm simply lucky.

Whoo hoo...3" high at a hundred. Who would have thought that what they have been printing for over 30 years was true?

Paul,

me and Seafire JR are taking an A/C automotive course over at the community college this summer together...I'm converting a friend's Grandma's car next Monday and then my 93 Camry...

A local autoparts store sells us the parts highly discounted being students over there...so we are doing the entire new dryer/receiver, the O rings thru out the system, ( retro fit kit) ester oil and one other part that escapes me...

they have the evac equipment over at the college, some new fancy stuff.... its running me about $85 for "grandma's car" next week... she's paying for the parts... she is insisting, and she can get a real b*tch if she doesn't get her way...

It's always nice when old time, print misinformation transitions to become Internet misinformation.

THE REDNECK METHOD:

25 yards using a white 5 gal bucket!

I'd like to see his actual tests to prove this with several rifles with scopes mounted at various heights like they are in the real world.

John, I have 30lbs of R12 you can have all you want.Ken

I would question how big these yards are, it makes adifference.

Jim

I'm the odd guy out. I figure there is likely a reason that crosshairs intersect. Since the scope makers were nice enough to get the 2 thingys to intersect I figure I should be nice enough and try like hell to get the bullet to hit where those 2 thingys cross.

It works to a point.

From the article.



The margin of error factor is really the kicker here. There are other factors not mentioned as well such as downrange ballistics for the bullet, rifle, rate of twist and height of scope.

The error you have at 25 yards is doubled every time you double the distance.

You will be a way more effective hunter and marksman if you zero and shoot at yardage commensurate to field or range conditions you hunt or shoot in.

Tiny errors at 25 yards don't show up till you're shooting at 200+. What you think is a perfect 25 yard zero could be 2-3" left or right down range.

I understand the military zeros at 25. A tyical 5.56 round will be almost a foot high at 200 yards and zeroed again at 300. Personally I think being a foot high at 200 is stupid. No wonder our soldiers can't hit anything.

I'll continue to zero at 100 and shoot at various ranges to know where I'm hitting. With anything I own I can still hold on hair out to 300 and make hits.

What? You don't want to shoot at 26 yards and know without a shadow of a doubt you can hit anything out to 300+ yards in the vitals?

No doubt about it not being the most accurate way to sight in a rifle, but...

When younger, it seemed like every year, the night before deer season opened, I would be sighting in my 30-30 at 23 yards (read that somewhere) using the truck headlights to see the target nailed to a tree.

It may not be the best way, but I killed a lot of deer. Of course, most of the shots were 75 yds or less.

That must be one short barreled rifle.

That is a key factor imo. A bullet should cross the line of site two times down range for optimum long range trajectory. Not just reach the line of site and immediately start descending. Scope height plays a big roll imo.

I've never understood why some embrace 'Kentucky' windage with a scope.

I'm betting the guy who wrote that article didn't even shoot one gun to verify what he wrote.

Seafire - the course and the project sound like fun. The good prices on the parts and the readily available nice equipment at the college make the complete overhaul worth it. By comparison, I am working in the AC dark ages out here.

I think that is what is called 'point blank' range. If I understand it correctly, its different for different loads, rifles, etc. But, the idea is that the rifle is sighted in where the bullet never travels above the 'line of sight' more than x inches and the the maximun distance for 'point blank' range is when the bullet drops below the 'line of sight' x inches.

and the higher the line of site over the center of the barrel the longer that range is extended as I understand it, within a practical degree of course. Ideally no more than the size of the kill zone of the animal that's being targeted. I use see thru mounts on my rifle that raises the line of site somewhat.

I'm mixed, on the one hand I'm happy I knew this already

otoh, I'm a bit sad to realize it's cause I'm so damned old.


new rifle, scope, rings or bedding, yep 25 yards to start

but as soon as dialed in then out to 100, 200, 300 (335 yards is the limit of our borough range, long range shooting for me has to take place in springtime via snowmachine to find a safe place to shoot with yardage out to 700+ yards.


again maybe it's cause I'm so old, but hunting seems far more productive ime, if it ain't a guessing game.

I start at 25 yards with a newly scoped rifle to get on paper for longer range testing, not for sighting in with the intent to shoot to 300 yards baddabing baddaboom.

Most idiots are happy to just hit the box at 26 yards....

This 25yd sight in with scoped rifles doesn't work for me. If hitting on at 25yrds it'll be way high at 100yds. I shoot at 25yrds to "get on paper" then move out to 100yrs and finally to 300yrs. Your mileage might very.

IMO 25 or 26 yards is a good starting point but it's a good idea to see where you're hitting with the same load at the max distance you're going to shoot it and in between that and 25/26 yards too.

I used to sight in at 100 yards then shoot and record hold over and under and tape the info on my rifle stock. I had data w/ my hunting load immediately available from 25-500 yards. I still do this but now have a LRF so I actually know the range and now it works. One of these days I will get a scope/knobs that allow me to quickly dial the range rather than use the marks on the reticle. Progress isn't all bad.

mike r

Mule Deer has addressed this fairly well in the past:
2009 Thread

And he is spot on with that!

Excellent response, John.

We called it the "thousand inch range" in the Marines. When you didn't have access to a full size rifle range, you could always find a 27 yard range with a backstop. That was used for the M-14 with peep sights.

Yeah, its a good thing Paul...the best is doing this stuff with my 20 year old son, sharing some more dad/son time together...

We are auditing the course, so no worries about tests, grades etc...my son took it last summer, so he is further along on the curve than dad is...gotta admit, when it comes to A/C.. my expertise ends with the old 4WD/70Mph school of thought...

i've been zero'ing at 25 yards for all my life. thats the way i was shown and it works for almost all calibers out to my reasonable shooting ranges. but theres no substitute for banging away at 200 yards to make sure.

While in theory the 25yd zero is good, there are some practical reasons that one should shoot at least to 100 when zeroing a scope.

Let's say you fire 3 rounds at 25 yds and assume the center of that group is really the true average center of the point of impact for the gun. Let's also say you have some parallax to the mix and say they stack up for a 1/2" error at 25 yds. That equates to a 2" error at 100 yds, and a 4" error at 200 yds. Let's say we're using factory ammo with a real world 2 moa accuracy. At 200 yds the 4" error plus the 4" grouping of the ammo means even without wind the shot could be 8" off the aiming point. That's enough to through the shot out of the vitals.

I can't imagine being too lazy to walk to the 100yd berm to set up a target, and I've found by pulling the bolt and lining up the bore with the target then zeroing the scope I'll be on paper and able to zero the scope in 10 rounds or less.

have always used 25 yards as a start when dialing in a newly mounted scope. if its where those cross hair thingy's meet I then go out to 100 and get it where I want it.