Is The O’Connor Zero Obsolete?

[okie john]

Before I went elk hunting this weekend, I zeroed my rifle 3" high at 100 yards as Jack O’Connor so often recommended. At last light, I held for a bull’s shoulder, fired offhand at about 110 yards, and smashed his spine. He dropped on the spot, which was nice since he was standing next to a hellish draw that would have required a helicopter to recover him had he manged to reach it.

But I was aiming for the shoulder, so I feel like that shot was a miss in some ways.

An elk's shoulder is BIG, so it's pretty clear that at least part of the problem is me throwing the shot high. But what role did The O’Connor Zero play in this? I’ve read that most mid-range misses are high because people get optimistic and zero for too great a distance. Thinking about it on the drive home, I began to wonder whether systems like Leupold’s CDS render The O’Connor Zero obsolete.

For mixed cover, does it make sense to zero dead-on at 100 or 150 yards since most shots will be around that range? Wiht a 150-yard zero, the typical 30-06/180 would be about an inch high at 100 and about two inches low at 200, which seems usable. It would be about 11 inches low at 300, but at that range you’d likely have time to dial in the range and hold dead on, which seems more precise than trying to hold a few inches high as with The O’Connor Zero.

Or do I need to stop overthinking this and get some sleep?


Okie John

[PNWTO]

I think O'Connor used this method to best compliment a great understanding of animal anatomy and eyes that were experienced in ranging. I think modern reticles, CDS, Kestrels, lasers, etc etc have really eliminated the need for such a zero, but for Bubba and his duplex reticle plus the trajectory listed on the back of the ammo box it is a handy method. My meat guns that have traditonal duplex reticles on the second focal plane are all zeroed at 200yds.

So, IMO, it is great for your "traditional" optics and freezer-fillers, but we have better methods now.

The misses I have seen at 250+yds have always been due to the inexperience of shooter and a poor range guess. I think most people will add range, and set up a 500yd shot for a 300yd target.

[SLG]

I prefer the point blank range zero, like you describe. Nothing outdated about it, just depends on what you want to do. I have guns I dial as needed, but the zero I walk out the door with is a point blank one. As an example, here is my 308. Zero at 200 yards. Bullet will hit within plus or minus 3 inches, from 10 feet out to about 250 yards. Within that range, I simply hold dead center. At 300 I hold slightly high, or I dial. Pretty simple, especially considering I almost never take a shot anywhere close to maximum range.

[Colt191145lover]

I asked my grandfather about the 3 inch high zero when I started hunting , He was not a fan at all. His reasoning was that shooting uphill and downhill most folks cant range effectively and he had seen a lot of guys overshoot the intended target , extreme angles being even worse . Understanding that we were always hunting in the mountains and hunting on the planes may be very different. As I have gotten older and have seen much of the same and myself have overshot my intended target a time or three , I tend to stick closer to a 100 or 200 yard zero on my hunting rifles. As always YMMV

[Unobtanium]

A zero is a personal question, so to say his zero is not a good or best practice, you would have to point to it failing HIM. I zero at 100. That works for ME.

[dbateman]

I think it's whatever works for you.


That being said, I like a 100yd zero for pretty much everything from 338 down, then I tend to go to a 300yd zero.

[BJXDS]

IMHO you just have to know how your rifle is zeroed, and be able to effectively judge distance and be able to hit within those parameters. The ideal zero would be the one with the least deviation from muzzle to max distance, less overall potential for error.

Sounds like you know you shot high, so if your gun/load was zeroed at say 200 and you had the same hold where would you have hit? Maybe 1 inch lower? Realistically no difference in results, or maybe you would have missed the spine and he would have been in the bottom of the draw.

I had a similar situation( in reference to guessing zero distance) 2 days ago with my muzzle loader that was zeroed at 100 yards, Monster Back at 250???. I watched him for an 1.5 hours and NEVER took the shot, because I didn't think I could make the hit. I thought about shooting 150grns vs 100grns of Pyrodex and Zeroing at 200, but I never did. In this case the ZERO would have made the difference, if I did my part. Yesterday I shot a deer at 20 yards. After muzzle loader season I am going to fix that.

My 06 is currently zeroed at +3 inches at 100, I may zero at 200 or maybe not.

[GJM]

Off hand and precise zero seem in conflict. I can work with any zero, but I can not shoot any shooting position up to the gun.

[SLG]

Off hand and precise zero seem in conflict. I can work with any zero, but I can not shoot any shooting position up to the gun.

That's is really the issue here.

[Al T.]

Long ago and far away, Ross Seyfried wrote an article advocating a 100y zero for his clients. In short, he noted everybody understood holding over at distance, few could hold under at close range.