Maximum point blank range and sighting in at particular distances...

[nastynate]

I use a Tikka 30-06, shoot 165 grain copper and a 3x9 scope (no dialing for me) for all my big game rifle hunting. This is not some target rifle, but what I would consider a pretty general purpose hunting rifle. I am not a shooting guru that is tinkering with handloads, not using chronographs, and not going to the range weekly. I'd suspect (thought I don't measure) that I shoot ~1.75" groups at 100, on average. I do have a rangefinder I use in the field.

Looking at a ballistic calculators... If I am zeroed at 250yards, I would be -3.7" at 300 and +2.8" at 100. Seems like a reasonable way to set up my rifle for a trip out west. Suppose I wanted to sight in this way. How would you go about sighting in at 250 yards? Do I do my best to get close to 2.8" high at 100? But my groups do not allow me to measure 1/10" that precisely, obviously. And 1/4" matters at that distance for where you're hitting down range. But I could do my best to do that, and then get some real worl data on where its hitting at further range. Or do I try to sight-in at 250 yards? In this instance, my groups start to grow and there are more factors at play... a bit of wind, certainly my aiming point has more error (even with benchrest), etc.

FWIW, I have it sighted in at ABOUT 2" high and this has worked just fine for me on multiple western hunts and stand hunting the woods back east. I think the farthest I've shot was about 260 and this setup worked just fine.

I'm just curious about your thoughts. People say "I'm sighted in at 2" high at 100" or "I'm sighted in at 200 yards" all the time, but I'm just curious how you go about doing so in the real world.

 

[kwyeewyk]

I shoot basically same load with 250 yd zero for the last 5 years, works great for me. You can take either approach you described and make it work, but best if you can shoot at both ranges to get confirmation and practice with your exact setup.

 

[nrpate05]

It is a good question. Before I started dialing, I would sight in zeroed at 200. My thinking was that most of my shots were in that range (150-250 yards), so that is where I wanted to be exact. When you start zeroing much further, your height at above zero at, say 150 yards, can be pretty high, like 4+ inches (especially with a slower round like the 30-06). I know that is within a kill zone, but I noticed that I would hit the spine on animals somewhat often. Eventually, what I tried to do was get it to where I'd be zeroed around 200, for 300, I just hold on top of a target (~8" drop) and then at 400 use the spot below the crosshair where the thin post meets the thick post. I never shot an animal that far, but I got it dialed in at the range where it was pretty consistent. When using that method, there is always a bit of guessing involved. Either way you go, just be sure to verify where you're hitting at the range.

 

[Ought Six]

Yeah sight in 2.8 at 100, then verify with groups down range, adjust accordingly

 

[nastynate]

Thanks for the answers! Good advice all around.

 

[Rie Bread]

Thanks for the answers! Good advice all around.

I just do 300 yard zero. Zero first 3” high at 100 and then check at 300.

 

[CoHunter1991]

50 yard zero. Easy to shoot well at that distance and you can be surgical with adjustments. Also has a redundant 0 at 165 ish

 

[Wind Gypsy]

Looking at a ballistic calculators... If I am zeroed at 250yards, I would be -3.7" at 300 and +2.8" at 100. Seems like a reasonable way to set up my rifle for a trip out west. Suppose I wanted to sight in this way. How would you go about sighting in at 250 yards? Do I do my best to get close to 2.8" high at 100? But my groups do not allow me to measure 1/10" that precisely, obviously. And 1/4" matters at that distance for where you're hitting down range. But I could do my best to do that, and then get some real worl data on where its hitting at further range. Or do I try to sight-in at 250 yards? In this instance, my groups start to grow and there are more factors at play... a bit of wind, certainly my aiming point has more error (even with benchrest), etc.

As you pointed out, if your groups are not that precise at 100, getting a good zero at further will likely be even more difficult. 2.8" high at 100 will probably be your best path. If you want a good zero with that level of precision you're going to want a good # of shots to get it, even 10 rounds has potential to misrepresent group center a little bit but that would be a good place to start.

 

[yakimanoob]

If you want a good zero with that level of precision you're going to want a good # of shots to get it, even 10 rounds has potential to misrepresent group center a little bit but that would be a good place to start.

+1 on this point.

The reality is that this kind of MPBR technique sounds great on paper (no pun intended), but the practical results you can expect are a lot less confidence-inspiring unless you spend a considerable amount of $$ properly establishing your true center point of impact. You said "But my groups do not allow me to measure 1/10" that precisely, obviously. And 1/4" matters at that distance for where you're hitting down range" and you're exactly right - small errors at short range between your true center of impact and the center that you observe from any given group translate to large errors downrange.

In my opinion, if you have access to a range that's long enough, you're FAR better off shooting 10–20 shots at 250 yds and measuring both your center of impact and your group size, and adjusting your scope to zero using that measurement. That will give you a much better sense of how your rifle is actually going to perform at the ranges you expect to be hunting, and saves you a bunch of headache trying to weed through the muck and mire of terrible advice that's common in the shooting world regarding what observations at short ranges (e.g. 100yds) can tell you about what you can expect at longer ranges (300+ yds).

For example, if you shoot 10–20 shots within an 8" circle at 250y, and set your scope to the center of that circle, you can be appropriately confident that your rifle will hit the vitals of a deer or elk at that range. Building that confidence from work at 100yds takes at least as many rounds and a lot more careful measurement and statistical inference.

Last point: I wouldn't worry about anything other than wind at these ranges. The effects of pressure, temperature, humidity, elevation, etc are negligible at these ranges.

 

[Wind Gypsy]

+1 on this point.

The reality is that this kind of MPBR technique sounds great on paper (no pun intended), but the practical results you can expect are a lot less confidence-inspiring unless you spend a considerable amount of $$ properly establishing your true center point of impact. You said "But my groups do not allow me to measure 1/10" that precisely, obviously. And 1/4" matters at that distance for where you're hitting down range" and you're exactly right - small errors at short range between your true center of impact and the center that you observe from any given group translate to large errors downrange.

In my opinion, if you have access to a range that's long enough, you're FAR better off shooting 10–20 shots at 250 yds and measuring both your center of impact and your group size, and adjusting your scope to zero using that measurement. That will give you a much better sense of how your rifle is actually going to perform at the ranges you expect to be hunting, and saves you a bunch of headache trying to weed through the muck and mire of terrible advice that's common in the shooting world regarding what observations at short ranges (e.g. 100yds) can tell you about what you can expect at longer ranges (300+ yds).

The issue is that results at 250 yards are more likely to be impacted by environmental conditions than those at 100 yards, creating another source for error in your zero that is already likely to have that error due to poor precision.

 

[yakimanoob]

The issue is that results at 250 yards are more likely to be impacted by environmental conditions than those at 100 yards, creating another source for error in your zero that is already likely to have that error due to poor precision.

It's true enough that the effects of environmental conditions will be greater than at 100yds, but the expected magnitudes of the effects are pretty small.

Assuming "nodope" factory specs, 165gr trophy copper 30-06s rounds will deflect less than 1 moa at 300yds -- not exactly a make-or-break difference if you're starting with a solid zero at 250.

 

[D4570]

I have a dial-up scope on my 8mm RM MAG rem 700 now.
I sent the Dope to Leopold and had them make a turret for my load—200 gr Hammer 3229 fps. I did a 10-shot zero at 100. It gives me a 5" group at 500 yards shooting off a bench aiming dead on.
But, I did the MPBR sight in before I had it, If I remember correctly it was like Zero at 238 yards. With that off a bench, I would group around 3" at 300 yards about 3" low. So I think an MPBR zero works very well.

 

[BAKPAKR]

I have a 125 gr Hammer Hunter load for my Remington 700 KS 300 RUM that is no more than 2” high or low out to a bit past 300 yards. That is my MPBR combo!

 

[Wind Gypsy]

It's true enough that the effects of environmental conditions will be greater than at 100yds, but the expected magnitudes of the effects are pretty small.

Assuming "nodope" factory specs, 165gr trophy copper 30-06s rounds will deflect less than 1 moa at 300yds -- not exactly a make-or-break difference if you're starting with a solid zero at 250.

1 MOA is what, a whole 4 or 5 MPH wind deflection at that range? In my opinion 1 MOA error in zero is a big error and if we're arguing about trying to get the best zero the method that leaves you with 1 moa error is the wrong one.

 

[yakimanoob]

if we're arguing about trying to get the best zero the method that leaves you with 1 moa error is the wrong one.

I agree. I wasn't trying to suggest that nastynate try to get a zero in a 5mph crosswind (or that he could ignore it). But on a calm day, it would allow him to skip the need for statistical inference (your and my affinity for such things notwithstanding ).

 

[yakimanoob]

But, I did the MPBR sight in before I had it, If I remember correctly it was like Zero at 238 yards. With that off a bench, I would group around 3" at 300 yards about 3" low. So I think an MPBR zero works very well.

It sounds like you spent a considerable amount of $$ properly establishing your true center point of impact.

 

[KingOfTagSoup]

I have personally found that setting zero at closer range and then verifying out farther works well. For example, if I shoot a group at 50 yds there is much more margin of error than at 250, meaning I can get a really good idea of where my point of impact is and be able to tell human error flyers easily. Then I'll calculate and adjust the dial for a mathematical 250 yd zero and most importantly, shoot at distance to verify. It should be noted however that doing this requires actual velocity data.

 

[D4570]

It sounds like you spent a considerable amount of $$ properly establishing your true center point of impact.

YUP, about $3 a shot. I have no idea how much that would be if I had to buy factory loads. The last time I saw factory shells for my gun was a few years back and they were well over $100 for 20.

 

[jt13]

Get on paper at 50. Find a solid 5 round zero at about 2.5" high at 100. Shoot at 200 & 300 to verify. Measure drops. Make a little dope sheet and tape it to your butt stock.

 

[elevatorman]

Any MPBR setup has two zero yardages. Decide the target zone size you want and put in your info. Bam. It'll give you the close and far zero yardages. Sight in at the close one.

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