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I would venture to guess most of the set-and-forget guys zero a rifle for 200 vs 100 and have a hybrid of MPBR/holdovers while still holding on vitals out to 400ish with most of the modern calibers. My question is, is there an advantage to setting your scope to 100 and knowing your holdover vs setting it to 200 and knowing the same? It seems like a blend of MPBR and 100 zero.... I have scopes that I spin but have a fair amount of set-and-forget yet with 200 yd zeros. Just honestly wondering what the benefit is between a 100 yd zero and 200 yd zero pending your fluent with holds and know your dope.
thanks in advance
You can zero at 200. However, there are many reasons to zero at 100.
First- if you do not have your bullets landing behind the crosshairs- aka POA/POI at that distance... you don’t have a zero. I.E.- zeroing 2in high at 100 is NOT a 200 yard zero regardless of what the math says. In that case you have a “2in high at 100 yard” zero.
Second, 200 yards is just far enough that environmental factors start mattering (wind, angles, etc.).
Third, to zero, and recheck zero you need 200 yards.
Fourth, I now have a trajectory that is both above and below my line of sight. And, a 200 yard zero doesn’t appreciably help with hitting at 300 or so.
The benefits of a 100 yard POA/POI zero.
One, 100 yard ranges are everywhere.
Two, 100 yards is close enough that environmental factors are not at play (excepting extremely high winds).
Three, because of the shape of high velocity trajectory, 100 yards is right in the middle of the flattest part. That means from 60’ish yards to 120 yards the bullet is never off more than 1/10th on an inch from LOS. You literally can set a target anywhere from 60’ish to 120 yards, aim dead on and have a 100 yard zero.
Four, every adjustment needed is high. There is no holding low, or hitting high. This matters. I’m always dialing up or holding high.
Now, having said that I zero everything at 100 for a POA/POI zero. That doesn’t mean one can’t dial up to a 200 or 250 yard zero out in the field. For cartridges/bullets 2,900fps or under, a 100 yard zero makes a very simple BDC style hold with a mil reticle. The dope ends up looking like so-
300- 1 mil
400- 2 mil
500- 3 mil
600- 4 mil
For cartridges above 3,000fps you may need to dial up a few tenths to make it linear. My 300 WM I can dial “UP .7” and my dope looks like this-
300- .5 mil
400- 1 mil
500- 1.5 mil
You can do that with any cartridge. You can also figure it out for a 200 yard starting zero as well, but there just isn’t a good reason to do so.
What about a hybrid of the two where you do MPBR for a smaller vital area, say 4-5”? Then you can still mindlessly aim dead on out to a set range, your max ord is lower in the middle ranges so you have some buffer built in, and anything beyond your MPBR is still far enough to give you time to range and dial? Seems like this method would take care of most of those misses at max ord.
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Of course that will work most of the time and is better than a true MPBR, but as above what is it really getting you? I mean with almost any normal centerfire cartridge these days and a 100 yard zero-
From muzzle to 200 aim center. Past 200 to 300 hold on the back. Past three hundred I’m not trying to hold in air.
If you bow hunt, I would wager that you don’t have 1 fixed pin thy you hold low on some shots, and guess how high to hold on others..?
I used to think that was obvious, but if you talk to many people you find it is not. The other thing is you'll usually run out of MPBR on windage before you get to MPBR on trajectory.
If you run the scenario with wind it gets ugly real fast for MPBR. Even a 4 mph wind calling ability (which is far better than non trained shooters can call it) drops the hit rate of the MPBR above to around 50%. Holding dead on is still in the high 90’s.