One shot zero

[Pistol Ranch]

I have a question.

Ignoring the one shot zero thing here for a minute, if you mount the gun in the lead sled, and shoot it once, see that youre on paper, somewhere, then shoot it again, without touching anything but the action to load the next round (even very carefully), will the second shot go "exactly" where the first shot did?

If it didnt, how will or can the "adjusted" zero make it happen?

Im not buying you can lock the gun in a vise and not have it move under recoil. If somehow you can, then you have to be interfering with the guns harmonics when fired.

Im suspecting that what some call "accurate", aint.

The rifle does not need to be in a lead sled...
If you are sure of your hold (sight picture) when the rifle is fired, the rifle can move.
Now, using sandbags, cardboard box, lead sled, etc. return the rifle to get the same sight picture.
Without moving the rifle adjust the scope crosshairs to center on the hole
in the target.
Done. (For me) I do not load a "second " round.Others may take over 39 additional shots to be absolutely sure.

 

[Joe Vaquero]

http://m.youtube.com/#/watch?v=NUWCUIuuFT0
Check out this vid on YouTube. Marlin firearms instructional video on how to sight in a rifle. Very similar to what I now like to call the "Pistol Ranch" method of sighting in a rifle.

 

[AK103K]

The rifle does not need to be in a lead sled...
If you are sure of your hold (sight picture) when the rifle is fired, the rifle can move.
Now, using sandbags, cardboard box, lead sled, etc. return the rifle to get the same sight picture.
Without moving the rifle adjust the scope crosshairs to center on the hole
in the target.

Using a lead sled, sandbags or some other method to hold the rifle absolutely solid, fire one shot on the target.

WITHOUT MOVING THE RIFLE, adjust the scope crosshairs to center on the bullet hole in the target..

Which is it? Or is it the same, only different?

 

[Pistol Ranch]

Which is it? Or is it the same, only different?

Exactly what do you see that is different ??

P.R.

 

[slowr1der]

Like I said, the reason it took me 39 shots was that I can't seem to hold this rifle still, due to the fact that I just can't get comfortable on holding my head in the right position, or holding the rifle at all when I'm shooting it on the bench. I also shot groups before making adjustments. I didn't adjust after each shot.

On my other rifle that fits me well, it usually takes about 5-7 shots to get it dialed in. I shoot it at 25 yards, see where it impacts and adjust. Take another shot. Then move to 100 yards and take a shot. I then make adjustments there. Then I take a 3-4 shot group just to verify it's where I want it to be.

For some reason I just can't do that with this other rifle though as I seem to shoot 3 or 4 in a group then pull 1. So that's why I don't just rely on one shot as it may be the one I pulled and instead I shot groups, then made adjustments.

 

[Pistol Ranch]

slowr1der: You are not alone..look at reply #89..

P.R.

 

[AK103K]

Exactly what do you see that is different ??

I know, its hard. Its just like one of those Goofus and Gallant puzzles, isnt it?

 

[kwelz]

1. I am 75 years old (not 16)
2. I am not a troll
3. I am a gunsmith and operated a business called "Guntuner". My specialty was accurizing hunting rifles.
4. I own a substantial collection of pre-64 Winchesters
5. I have been reloading since the 1960's
6. If you have any doubt about my abilty to do as I say/post, P.M me when you are in the Houston area for a demo.You pay the range fee.
7. I CCW
The ball is in your court..

I don't see one qualification in there that shows that you have the level of knowledge to override everyone else who has been teaching people how to Zero.

75 or 16, the advice you are giving is irresponsible and possibly unethical in a hunting situation.
Reloading, owning a bunch of pre-64 Lever actions, etc. Don't really give any qualifications in this regards. The only one that comes close is the accurizing hunting rifles. And remind me never to have you do any work since 1 shot really isn't a test of accuracy in most peoples books.

 

[Tim the student]

Pistol Ranch, will you explain what it means to have a rifle zeroed? Not how to do it, but what it means.

 

[Pistol Ranch]

Tim:
On a scoped rifle, the scope sits above the bore. As soon as a bullet exits the barrel, gravity takes over and the bullet begins to fall.
If the scopes LineOfSight and the rifles bore are absolutely parallel, no "zero" would be possible.
In order to zero a rifle, the scope must be pointed slightly down in order for the bore and sight line to intersect.
The fallacy exists that the bullet rises above the line of sight..this is B.S.
A bullet travels a parabolic arc. When the bore is "aimed" above the line of sight, the bullet actually passes thru that arc twice. Once as it travels upward past the L.O.S and again as it passes downward at some point downrange. There is no "rise" to it, the bullets trajectory is shaped by its weight, velocity and its ballistic coefficient.
I typically zero rifles at 100 yards, so that rifle/bullet combination are set up for the bullet to intersect the L.O.S. at that distance and thats what I call zero.
You see other posts in this thread where shooters claim zeros at 100, 200 and other yardges. What they call zero is simply the mean center of a group of shots at whatever range they are shooting. True zero, in my definition, is where the L.O.S. and bullet converge.
If you are not reasonably sure of what your rifle might do at 100 yards, it is not a bad plan to start the process at 25 yards. Since most scopes are set up to move the point of impact 1/4" for each "click" of elevation or windage at 100 yards, it will take 4X the number of clicks to move the point of impact the same distance on a 25 yard target.
All this of course is not rocket science; despite what you may have read.

P.R.

 

[Pistol Ranch]

Kwelz: What you (and others) don't seem to understand is that I said that is was
possible to zero a rifle with one shot.
I did not advocate that one shot was the ONLY way to do it.
You are welcome to teach others how to shoot any way you like..
Perhaps you need to start a thread of your own where you give us the value of your expertise.
Perhaps you could list your qualifications as a firearms instructor.
I am sure that it would be of benefit to all who seek knowledge on this forum.

P.R.

 

[MCMXI]

You see other posts in this thread where shooters claim zeros at 100, 200 and other yardges. What they call zero is simply the mean center of a group of shots at whatever range they are shooting. True zero, in my definition, is where the L.O.S. and bullet converge.

So in your world, a 100 yard zero is superior because the bullet and line of sight only intersect once, whereas with a 200 or 300 yard zero, it's not really a zero because the bullet's path and line of sight intersect twice?! Seriously?!!

 

[dnthmn]

So in your world, a 100 yard zero is superior because the bullet and line of sight only intersect once, whereas with a 200 or 300 yard zero, it's not really a zero because the bullet's path and line of sight intersect twice?! Seriously?!!

While a disagree with PR's method as a good method; he in no way, shape or form said it has anything to do with how many times a bullet crosses the LOS.

Additionally, there is only one range for each rifle/load combo that intersects the LOS at one point and that point will vary with each combo. If you did that, you'd have odd ball zeros like 57 or 83 yds.

 

[Tim the student]

I typically zero rifles at 100 yards, so that rifle/bullet combination are set up for the bullet to intersect the L.O.S. at that distance and thats what I call zero.

Thanks for that.

I said that is was possible to zero a rifle with one shot.

I took the rifle to the range and shot a M.O.A. group that was 1" high and 1/2" right at 100 yards with no scope adjustment.

And here you proved that it is just as possible to not zero a rifle in one shot.

Sounds like you just showed that it may get you close (and may get you dead on), but also that it just as easily may not get you zeroed by your own definition of the word.

 

[MCMXI]

dnthmn, so how do you interpret this then ....

True zero, in my definition, is where the L.O.S. and bullet converge.

For a 200 or 300 yard zero, this will occur twice at two clearly defined ranges, one of which would obviously be 200 or 300 yards. In practical terms, for a 100 yard zero this will occur once. In reality, we all know that the bullet's path will cross the line of sight somewhere before or after 100 yards, but the flight path is virtually flat for 20 or 30 yards depending on the cartridge. So how is the OP's zero a "true zero" compared to a 200 yard or 300 yard zero? The only thing I could think of late last night is that the OP considers that a 100 yard zero has one practical convergence whereas longer zeros have two clearly defined convergences. Basically, I don't see how a 200 or 300 yard zero is not a "true" zero.

 

[Slamfire]

I regularly, if not every weekend, am shooting Highpower, small bore, or long range. I am only limited by the number of events in the area.

I can look over my data books and same gun, same load, see my zero’s slightly changing, up or down, over time. There might be an “average”, but when it really gets down to being perfectly in the middle, a click or two, usually more, is not unusual.

I don’t know why. But I am shooting hand held rifles, not shooting off a 500 lb concrete bench with ninety pounds of sandbags, I figure the variation is due to me and the dynamics of my jelly roll. Somedays it is firm, other days it is not.

Another reason why I don’t think people should be shooting at deer/elk/etc beyond 300 yards. Even with a known zero, first shot is not going to be in the middle.

The further you get the worse it gets. I arrive at a 1000 yard match, same range, same rifle, same ammo, zero from last match, and I am happy if my first shot is in the black. Talking in the pitts with a Wimbleton Cup winner, we both were wondering about those sniper dudes who always get head shots, first shot, at 1000 yards, when we are just happy to be not to be in the white.

 

[txhoghunter]

we both were wondering about those sniper dudes who always get head shots, first shot, at 1000 yards, when we are just happy to be not to be in the white.

At longer ranges, snipers are trained to aim center mass for the majority of their shots

 

[MrSpiffy]

PR, I think the point that everyone that is disagreeing with your method is trying to make is this:

Every rifle shoots groups, not single holes. It doesn't matter if you bought it for $50 or $5,000, how much stuff you bolt onto it, or how much work you've done to tune it. It shoots groups. They might be very, very small groups. But they're still groups. Therefore, you cannot claim that a single shot will "zero" a rifle, whatever your definition means (same hole, or that your first shot was center of the group). And any ammo you have may produce fliers, hand-loaded or factory. It is absolutely, 100% impossible to claim a zero at any distance, with any ammo, for any firearm, because they all shoot groups, not single holes. Take a 30-30, for example. Many shoot 2" groups or larger at 100yds. They're not the most-accurate rifles out there, but they're plenty good for hunting at shorter distances.

Without multiple shots, you'll never know if your first shot was in the middle of the group, the outside of where the group would have been, or maybe even a flier that wasn't even close. The best bet to zero means multiple shots and choosing accurate ammo through testing, not to mention solid marksmanship skills and a good rest. Most people zero to the center of a group, as we cannot trust a single shot to be the end-all be-all of accuracy in a gun.

We get your method. We understand that it will get you very close to zero, assuming that the first shot was solidly made and not a flier. But it's not a reliable way to get to a real zero. Good enough? Maybe in many cases. But not zero. In reality, there is no zero. Just "middle of the group".

You being a gunsmith, I hope this concept can be understood. Does this explanation make sense to you? Not trying to be sarcastic. Just thinking it may not have been explained clearly enough before.

 

[Pistol Ranch]

Spiffy:
I hear what you are saying. Once again, I said that a one shot zero is possible. Just for fun you might look up the definition of that word.
Reading thru this thread and its companion (The poll) I find that there are as many ways to "zero" a rifle as there are posters in this thread and the poll.

I am in no way advocating that one shot is the only way to zero a rifle.
Use whatever method you have used, learned or are comfortable with.

You might be interested in the fact that I normally use a three shot group to establish a final scope setting..but that will only open up the thread for more discussion that three shots are not enough!!

Does this make sense to you ?? No sarcasm intended...

Have a good day

P.R.

 

[Leaky Waders]

I really don't see what all the debate is about.

The method described just confirms adjustment of the scope based upon the last shot.

When one fires a well placed shot, from a rest like a caldwell lead sled, and can recall the exact sight picture. Then one can either click their scopes for windage and elevation to adjust the sights by measurement/clicks...or take the variability out of the measurement of the scope makers clicks and move the crosshairs to the actual hit on target.

This is what shepard scopes is all about...I don't own one but have read their literature and understand their one shot zero concept. One is simply visually verifying the scope's adjustment rather than depending on the manufacturer's clicks to move the reticle to the last shot.

Variability introduced by the rifle (does it shoot one two or three minute of angle) vs ammo (for all these people who shoot mil surp because it's cheap but their targets look like #4 buck patterns) to windage and temp conditions to the most common culprit for weird fliers and misses - me and my fellow shooters - will always be there.

I don't think anyone is advocating buying a new rifle and taking it hunting after one shot. But for the persons who use this method, you'll see them on the range...like I was yesterday, with a newly scoped rifle like I was yesterday, shooting and making one adjustment like I was yesterday, and then enjoying 19 more rounds at various ranges without fiddling with scope clicks and caps.

For those shooting the 3 - 5 shot method, who are clicking their scopes at the 25 yard line they will eventually start shooting at the 200 yard range...but they will waste more bullets while accomplishing the same goal.

It's just more efficient...it's nothing to do with being right or wrong. Try it. For hunters it really works. For those olympic shooters I'm not so sure - it seems like it should, but who knows?

LW

PS I killed a lifesized prairie dog target twice yesterday at 200 yards...one with an appendix shot and one with a bull's eye...made my day.

 

[Slamfire]

we both were wondering about those sniper dudes who always get head shots, first shot, at 1000 yards, when we are just happy to be not to be in the white.

At longer ranges, snipers are trained to aim center mass for the majority of their shots

I did not add enough sarcasm, so I will try again.

Internet sniper dudes always make head shots at 1000 yards.

It is just that we never see them at the matches we attend.

 

[Brian Williams]

I am sticking a fork in this. Yup, it is done.

Obtw, 1858, a bullet will always cross the scope line of sight 2 times. Once normally around 25 to 40 yards and then again where you have adjusted the scope to be at zero, be it 100, 150 , 200 and maybe even 500 yards.

 

[MCMXI]

Obtw, 1858, a bullet will always cross the scope line of sight 2 times. Once normally around 25 to 40 yards and then again where you have adjusted the scope to be at zero, be it 100, 150 , 200 and maybe even 500 yards.

I know it does ... but with a 100 yard zero, you could be fooled into thinking that it only crosses once since the bullet's path is almost flat at the top of its trajectory. That's what I thought the OP was alluding to and I still don't get why the OP thinks that 100 yards is better.

As for where the bullet crosses the line of sight with a 100 yard zero, that'll depend entirely on the cartridge in question. My 178gr A-MAX (.308 Win) with a MV of 2,650 fps will cross at 80 yards with a 100 yard zero but the path is for all practical purposes flat from 60 to 120 yards.

 

[taliv]

Talking in the pitts with a Wimbleton Cup winner, we both were wondering about those sniper dudes who always get head shots, first shot, at 1000 yards, when we are just happy to be not to be in the white.

no kidding.

but seriously, i am usually disappointed when my first sighter is a mid-9 or worse, especially if i'm on relay 1 before the wind picks up

 

[MCMXI]

Talking in the pitts with a Wimbleton Cup winner, we both were wondering about those sniper dudes who always get head shots, first shot, at 1000 yards, when we are just happy to be not to be in the white

Maybe that's the problem ... if he'd won the Wimbledon Cup perhaps he'd know.