36 yard zero

I do this for all of my small frame ARs (except my Mod H) and it does work. Zero at 36, POA = POI at 300. This includes 10.3” and 14.5” using 55g IMI and 77g Mk262 and BH equivalents. Also works for 308 as my SR25 has a Trijicon RMR in a 45 degree offset mount.
 
I do this for all of my small frame ARs (except my Mod H) and it does work. Zero at 36, POA = POI at 300. This includes 10.3” and 14.5” using 55g IMI and 77g Mk262 and BH equivalents. Also works for 308 as my SR25 has a Trijicon RMR in a 45 degree offset mount.
In the offset mount do you do a offset zero since it isn’t directly over bore?
 
In the offset mount do you do a offset zero since it isn’t directly over bore?

Nope, It’s over the bore (the bore is round), just not on the top of the receiver....You zero it the same way, except you first orient the weapon so that the secondary optic is straight up/down (and the primary becomes off set relative to the secondary optic).....Zeroing the dot is, otherwise, no different than if the secondary optic was mounted to the top of the receiver.
 
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It's nothing you can't figure out with a ballistic calculator. In ballistic ae for example you can set a vital zone radius and in the chart it will give you the zero range and max range to hit inside that radius with no hold or adjustment.
 
The 36/300 zero is where it’s at for irons or red dots. If you only have 25 meter/yard lanes, just do the math for the offset. If you hate math, targets have the offset marked for use at 25.

I’ve been using 36/300 since 2003 and am baffled each time I go to a training or cert course and they promote the 25/50/200. What’s worse is when you show them the numbers and they just shrug and say this is how we’ve always done it.

If you aren’t convinced, put a waterline on a large target backer and see for yourself how they compare at each yard line.
 
The 36/300 zero is where it’s at for irons or red dots. If you only have 25 meter/yard lanes, just do the math for the offset. If you hate math, targets have the offset marked for use at 25.

I’ve been using 36/300 since 2003 and am baffled each time I go to a training or cert course and they promote the 25/50/200. What’s worse is when you show them the numbers and they just shrug and say this is how we’ve always done it.

If you aren’t convinced, put a waterline on a large target backer and see for yourself how they compare at each yard line.
Sorry for my ignorance, can you explain the large target waterline test? Thanks.
 
Sorry for my ignorance, can you explain the large target waterline test? Thanks.
Of course man.
So you’d take a clean target backer (not just a sheet of paper) and put a clean/sharp horizontal line across it with a small vertical mark for a clean POA. You take your zeroed rifle and then shoot your target while aiming at the waterline, regardless of the distance. This will give you a solid vertical POA so you’re able to measure the rise and drop of the projectile at each distance.
That’s it at a basic level/setup. Depending on the size of your backer, you can set up different target/range zones so you don’t have to walk down after each group and paste/mark holes. You can also just set up paper at all distances and just do it that way as well.

Pretty much doing the same thing that we (should) do with our precision rifles, we should do with our others. The reason for doing it this way is that you typically aren’t dialing for distance with your irons or red dots. Sure there are irons that have the ability to do so, but engagements are typically always done with holds (excluding those that run certain matches or “back in the day” doing quals).

Running a test like this allows you to visualize and confirm the exact POI shift at each distance with your setup. Regardless of what BZO you use, you should be doing this if you’re running irons and/or a red dot.

Let me know if that doesn’t make sense and I’ll try again. It’s 3am and I’m jet lagged with a screaming toddler in a hotel. So for all I know is that I just typed out a recipe for some bad ass lasagna. lol
 
I use a 50yd zero for my scoped .223 has coyote rifle, using ammo in the 62gr-69gr range, because I get plenty of close shots. It’s always given me good results out to the max 250yd shots I typically have, in the area I work. I’ve been wondering whether the 36yd would be better but I don’t really see how the 14yd distance change would have some drastic effect? I’m guessing this is all highly dependent on the velocities you’re getting in your particular rifle? Like, a 18” bbl shooting 55gr might be better suited whereas a 10.5” bbl shooting 77gr might not be as well suited?

How does the 36yd method work with a short barreled 300Blk shooting something speedier like a 110gr pill? I’m about to add a offset MRD and maybe a 36yd sight-in would be good for it and then go back to a standard 100yd zero with my variable power scope?
 
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I use a 50yd zero for my scoped .223 has coyote rifle, using ammo in the 62gr-69gr range, because I get plenty of close shots. It’s always given me good results out to the max 250yd shots I typically have, in the area I work. I’ve been wondering whether the 36yd would be better but I don’t really see how the 14yd distance change would have some drastic effect? I’m guessing this is all highly dependent on the velocities you’re getting in your particular rifle? Like, a 18” bbl shooting 55gr might be better suited whereas a 10.5” bbl shooting 77gr might not be as well suited?

How does the 36yd method work with a short barreled 300Blk shooting something speedier like a 110gr pill? I’m about to add a offset MRD and maybe a 36yd sight-in would be good for it and then go back to a standard 100yd zero with my variable power scope?
I’ve never run a 300blk but you can check out the shifts by plugging the data into a ballistic calculator.
 
Good info here. I still use the 100 yard zero though. Everything is nice and tight until 200 yards or so. I don't really expect to have issues with my SBR past 200, could be kind of hard to explain why I felt threatened at that point. If I was engaging a target past 200 with a RDS, a head hold would produce a center of mass impact...
 
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Screenshot_20200213-235139_Strelok Pro.jpg


Sorry 350 some
Forgot to switch tifles
 
Started using a 36 meter zero as a recruit in 1997. Would be willing to bet that the Marines were using it for decades by then.

Rear sight elevation on 8/3, and presto magico...you were right on at 300 meters as well.

Been a couple years since I retired...did the Corps stop doing this?
Was just gonna say this. USMC was/has been using the 33m (36y) zero for many, many moons.

They got upset whenever their Doc would outshoot them ?
 
It is about .1 MIL difference than a 25 yard zero and a 36 yard zero on the SKS is really a 26 to 52 yard zero. This is a case for Mr. MOA. Shooting smaller groups on a short zero don't make them smaller at 100. I used the Litz test. I set up a target at 25 and a much larger one at 100 directly behind it. I shot a tight group at 25 and the strangest thing happened at 100.
 
This is a great video. 36yd zero, then memorize the remaining holds throughout the effective range of my load (bullet's min velocity for expansion, min energy, etc). Most should be good past 300yds, even with shorter barrels.
 
39 yard zero is actually my mpbr for 223 out to 420 with 3 inch spread
That is about where I ended up looking just at calculations.

To me, you have to look at the whole system.

Sight: You are running a red dot- what MOA is it 2MOA, I have astigmatism, so mine is a bit bigger when turned on 'normal' instead of dimmly for sighitng.
Rifle/Ammo- I run M193 bulk stuff, what is that 3MOA by spec? Maybe 2MOA (as in 10 shots in 2MOA)
Shooter- Sure, prone out, with a bipod to zero the gun, but I'm almost always shooting offhand, or at best mag-monopodded, and shooting fast.

So you have your scope 'cone', your ammo/rifle 'cone' and your shooter 'cone'. It seems like a 30-40 zero puts the most hits closest (or actually in) the scope MOA zone out to 300.
 
Here's a table of bullet drop I created out to 300 yards that shows the effect of different zeroing choices. The 36 yard zero wins. It drops the least across 300 yards (8.57"). It produces the narrowest range between the maximum rise and drop values (9.86"). Here's the most impressive thing: The average drop along the whole trajectory out to 300 yards is lowest (-1.36"), and the median average is also the lowest at -.41 inches. The only category in which the 36 y zero loses is it produces that greatest rise along the trajectory, and that's at 100 yards (1.29"). If you KNOW you're going to be shooting targets at exactly 100 yards, then the 100 yard zero (obviously) or even the 25 yard zero are ideal. But if the range of your target could be anywhere out to 300 yards, your best choice among those shown is the 36 yard zero. Shawn is correct based on this analysis.
Zeroing ballistics.jpg
 
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Only skimmed the comments but some of y'all are missing the point... there is no 50 vs 36 vs 25 discussion, they all accomplish different things especially with different barrel length and ammo combinations. If you want to be able to hold on someone's face and pull the trigger without needing to think about anything, 50 can facilitate that - the other two can't. On the flip side, if you are guarding some tower and the terrain is very open and far, 25 or 36 might be the way to go.

The only time I would say "yes you should you [X]" is with iron sights. You never want to hold over with iron sights, only under. Therefore the 25 or 36 will for most be by default better.
 
Here's a table of bullet drop I created out to 300 yards that shows the effect of different zeroing choices. The 36 yard zero wins. It drops the least across 300 yards (8.57"). It produces the narrowest range between the maximum rise and drop values (9.86"). Here's the most impressive thing: The average drop along the whole trajectory out to 300 yards is lowest (-1.36"), and the median average is also the lowest at -.41 inches. The only category in which the 36 y zero loses is it produces that greatest rise along the trajectory, and that's at 100 yards (1.29"). If you KNOW you're going to be shooting targets at exactly 100 yards, then the 100 yard zero (obviously) or even the 25 yard zero are ideal. But if the range of your target could be anywhere out to 300 yards, your best choice among those shown is the 36 yard zero. Shawn is correct based on this analysis.
View attachment 7395854

How does all that equate to a person shooting 2 to 3 MOA accuracy since this is a battle zero we are talking about? On your calculator you show it is superior. But by what percentage vs a 25 yard zero? Is it material? Easier softer ways avail us nothing. Using iron sights the SKS manual calls for a 100 meter zero prone with just a sling. Does that back into a 36 yard zero? Your rifle zero is only correct at two distances. What is the other one?
 
How does all that equate to a person shooting 2 to 3 MOA accuracy since this is a battle zero we are talking about? On your calculator you show it is superior. But by what percentage vs a 25 yard zero? Is it material? Easier softer ways avail us nothing. Using iron sights the SKS manual calls for a 100 meter zero prone with just a sling. Does that back into a 36 yard zero? Your rifle zero is only correct at two distances. What is the other one?

There's a lot of information in the table. I imagine it could be "applied" in any number of ways.