Confused on how to have two zeroes for two different loads.

[hidaro]

I'm shooting an 18" gas gun with a BDC reticle.

My primary load is IMI 77gr @ 2710fps. I zero it at 63 yards in order to match my BDC.

My training load is PMC XTAC @ 3120fps. I zero it at 100 yards in order to match my BDC.

If both loads were zeroed at same distance, I could just measure the POI difference between the loads and dial. So I'm guessing now I'd need to measure the POI difference (if applicable) and THEN use Strelok to know how many clicks to go from 63 -> 100 and vice versa.

Here's the issue. If I'm currently zeroed at 63 yards with my 77gr and want to move to 100 to use my 55gr, Strelok says it'd take 2 clicks down with the IMI 77gr selected, and 3 clicks down with the PMC selected. I don't know which I'm supposed to use if I'm trying to move from a 63y 77gr zero to a 100y 55gr zero and vice versa.

 

[Hickswr]

This made my head hurt.

Solution- get a scope with a mil or MOA reticle. Record the difference in the two zeros at 100 yards. Set Zero for bullet of choice at 100 yards and then use a ballistic solver and dial yardage or use reticle for hold overs.

 

[hidaro]

This made my head hurt.

Solution- get a scope with a mil or MOA reticle. Record the difference in the two zeros at 100 yards. Set Zero for bullet of choice at 100 yards and then use a ballistic solver and dial yardage or use reticle for hold overs.

getting a different scope doesnt answer my question

 

[Hickswr]

getting a different scope doesnt answer my question

You already answered your own question- just do what you stated.

“If both loads were zeroed at same distance, I could just measure the POI difference between the loads and dial”

 

[salks]

Shoot all loads at 100y and measure the difference.

 

[whatsupdoc]

What?

"Strelok says it'd take 2 clicks down with the IMI 77gr selected, and 3 clicks down with the PMC selected"

2 and 3 clicks down from what zero?

Maybe I am not following the bouncing ball but cant you zero the one load then adjust the elevation
for the second load and just switch between the two settings.

 

[hidaro]

f

You already answered your own question- just do what you stated.

“If both loads were zeroed at same distance, I could just measure the POI difference between the loads and dial”

I can't zero both loads at the same distance, that's the issue. 77gr needs to be at 63y for BDC to line up.

What?

"Strelok says it'd take 2 clicks down with the IMI 77gr selected, and 3 clicks down with the PMC selected"

2 and 3 clicks down from what zero?

Maybe I am not following the bouncing ball but cant you zero the one load then adjust the elevation
for the second load and just switch between the two settings.

My primary load and zero is 77gr @ 63y. It has to be at 63y for the BDC to work.

However, I like to use 55gr for plinking. It has to be at 100y for the BDC to work.

The amount of clicks needed to go from 63y to 100y is dependent on the velocity of the round you are using. I'd need to go from my 63y zero which I use for my 77gr stuff, to a 100 yard zero for use with my 55gr stuff. Strelok says 2 clicks for 77gr stuff. 3 clicks for 55gr stuff.

 

[_Windrider_]

Zero your scope for the flattest shooting round, then shoot the other one and note the poi shift. It’s really no different than shooting suppressed and unsuppressed.

 

[nn8734]

f


I can't zero both loads at the same distance, that's the issue. 77gr needs to be at 63y for BDC to line up.



My primary load and zero is 77gr @ 63y. It has to be at 63y for the BDC to work.

However, I like to use 55gr for plinking. It has to be at 100y for the BDC to work.

The amount of clicks needed to go from 63y to 100y is dependent on the velocity of the round you are using. I'd need to go from my 63y zero which I use for my 77gr stuff, to a 100 yard zero for use with my 55gr stuff. Strelok says 2 clicks for 77gr stuff. 3 clicks for 55gr stuff.

What scope are you running?

 

[Aftermath]

WTF?
Zero for the load that impacts low at 100 yards and set the zero stop. DOPE yourself to whatever yardage you like. Write all that shit down.
Now, dial back to zero and shoot the load that impacts higher at 100. Find the zero dial up. Make a note of this "zero". Now, DOPE yourself to whatever yardage you like. Write all that shit down.

It doesn't matter what scope you are using.
EDIT: I guess it matters a little if you don't have a zero stop scope. If not, upgrade to one that has zero stop just for the simplicity.

 

[hidaro]

WTF?
Zero for the load that impacts low at 100 yards and set the zero stop. DOPE yourself to whatever yardage you like. Write all that shit down.
Now, dial back to zero and shoot the load that impacts higher at 100. Find the zero dial up. Make a note of this "zero". Now, DOPE yourself to whatever yardage you like. Write all that shit down.

It doesn't matter what scope you are using.

you didn't read my question

 

[Hickswr]

Forget the BDC (BDC reticles suck).

Zero both at 100 and record the adjustments needed between each bullet.

Set 100 yard zero for desired bullet and DIAL yardage (DON’T USE THE BDC) and just use the center crosshair.

If u want to holdover, get a MIL or MOA reticle.

 

[Precision Underground]

I think you’re letting the solver make it too complicated. If all you want to do is hold with the BDC- Zero the 77gr load. Now shoot the 55 gr load at 100 and note where you need to turn the turret to zero it. Mark the turret where it zeros the 55gr load at 100. Now you can start at zero and use the 77gr to hold over or you can start at the mark and use the 55gr to hold over.

If you want to be able to dial-
Zero the 77 gr load where you want it zeroed. Now shoot the 55 gr load at 100 and input the impact location into your solver. Don’t turn the turret to zero. In your solver set your zero as not on center, usually called zero offset I think(random example 1.5” high and .5” right or wherever it lands). Then you can just select that bullet and find the distance you want and it will tell you where to dial.

 

[nn8734]

you didn't read my question

And you haven’t read mine.

Some of the above responses provide the direction you need to try and solve your problem with your existing optic though no fucking way im dealing with a scope that requires me to do that shit just to also shoot substandard 55g stuff…Get either a mil based scope or scope that uses a .308 bdc reticle so its in synch with your primary 77g load. Zero at 100m

Run your 55g shit at csc distances or when the targets <=50m. Shoot e types to learn where your holds need to be at those close in distances.

Dont overthink this.

 

[KnowNothing256]

@Precision Underground has the right way. Go to the range, zero your “primary” load at your desired 63 yards, then change the ammo, move to 100 yards, and shoot at the center of your aiming point without touching the scope. This will tell you what adjustment you need to make to move that 55gr load to your POA at 100 yds, and that adjustment is what you’ll need to make on the scope when switching loads.

 

[Gil P.]

Just throw your piece of shit scope away and take the advice given to you in the previous posts.

You're making things more complicated than they need to be. If you don't understand how to use a scope with mil reticle and mil turrets, learn how. The end. Problem solved.

 

[Aftermath]

you didn't read my question

I read it.
It's a very simple problem with a very simple solution.
Complicate it as you will.

 

[hidaro]

@Precision Underground has the right way. Go to the range, zero your “primary” load at your desired 63 yards, then change the ammo, move to 100 yards, and shoot at the center of your aiming point without touching the scope. This will tell you what adjustment you need to make to move that 55gr load to your POA at 100 yds, and that adjustment is what you’ll need to make on the scope when switching loads.

Just throw your piece of shit scope away and take the advice given to you in the previous posts.

You're making things more complicated than they need to be. If you don't understand how to use a scope with mil reticle and mil turrets, learn how. The end. Problem solved.

Thank you! Makes sense.

Just throw your piece of shit scope away and take the advice given to you in the previous posts.

You're making things more complicated than they need to be. If you don't understand how to use a scope with mil reticle and mil turrets, learn how. The end. Problem solved.

I know how to use mil reticle and mil turrets. This is a fighting rifle and I want to retain BDC for agility.

 

[Aftermath]

This is a fighting rifle and I want to retain BDC for agility.

 

[Gil P.]

Thank you! Makes sense.



I know how to use mil reticle and mil turrets. This is a fighting rifle and I want to retain BDC for agility.

It doesn't sound like its working. Don't make yourself struggle.

 

[waveslayer]

Thank you! Makes sense.



I know how to use mil reticle and mil turrets. This is a fighting rifle and I want to retain BDC for agility.

All my rifles are fighting paper, so I guess they are fighters too... you have way over complicated this and your BDC reticle is only good for that exact load/rifle the BDC was made for. Get a standard Mil or MOA scope and problem solved. I run 1 scope on my DT with 6 different calibers without any issues

 

[Near miss]

If you cannot zero it at 100y..

Your strelok gun profile has 100y zero for the imi load.
So to enter your PMC profile, enter new cartridge and input distance to 63y.
Then change the zero until it matches your PMC zero.

I recommend zeroing to whatever distance you most often can shoot / verify

 

[Ledzep]

Zero the one that requires a 63yd zero at 63 yards.

Shoot the 100yd zero load at 100yd.

Note POI error.

Dial that difference when you shoot that load.

Reverse that dialing when you go back to the other one.

 

[DocRDS]

Wait--lemme get this straight.

As a "Warfighter" with a "fighting piece of kit" and an experienced "rifleman" you are using strelock to figure our your adjustments from 63 to 100 yards and vice versa?

On a "fighting" rifle.

You are woried about 1 click difference.

Lemme put on my Bear Pit Hat

1 sec

MIL or MOA?

Now granted, I am old, fat, partially blind, never served in the "sandbox" nor train in any "Tier 1" units and I tend to favor my AK over the AR (its got the magnifier!), but I'd say learn to zero at 100, and learn your holds and learn to fucking send it.

But...but....but MUH BDC!!!!

Plus the fact you are struggling over 0.2 or 0.3 AT 100(63) YARDS!!!


(1)Go to the range, Put your dumbass BDC on the target at 100 yards. Fire 5 shots (pick one and ONLY one of your ammo selections)
(2)Now, take the second ammo selection. put your dumbass BDC on the target (pro tip--aim at the same point) and fire 5 shots.
(3)Wait for the range officer to call a cease fire (if shooting alone--thats YOU!)
(4)Pick up a tape measure.
(5)Walk to the target
(6)Measure the vertical distance between the groups assuming you haven't hamfisted some 6MOA group with your booger hook.

(7)Then pull the caps off your scope. Get the instruction manual as well. Figure out if it is MOA or MIL. Also figure out the subtensions in your crosshair.
(8)Google MOA or MILs to Inches and 100 yards and do mafs
(9)Now using that magnificient pience of warfighting kit, MEASURE THE DISTANCE IN THE SCOPE.
Your answer should match. If it doesn't go back to 2nd grade and learn basic math
(10) You passed basic math. Now take the number from step 8 and 9. Take that number and divide it by the value of 1 click. (be careful--it could be 0.1, 0.25, or even 0.5!--if division is hard, multiply by 10, 4 or 2)
(11) You now have your offset. Notice, we did not zero the rifle. We just looked at the POI of the groups.
(12) Bonus exercise: 15 points if you can explain why your BDC won't work at long distance for 55gr
(13) who the fuck has a 63 yard range?

 

[Bacarrat]

Don't be poors and just shoot 77gr ammo. That's what I do. Having multiple zeros and zeroing at 63 yards to match a BDC is stupid. BDCs are stupid to begin with. This isn't the 80s.

 

[OREGUN]

Wait--lemme get this straight.

As a "Warfighter" with a "fighting piece of kit" and an experienced "rifleman" you are using strelock to figure our your adjustments from 63 to 100 yards and vice versa?

On a "fighting" rifle.

You are woried about 1 click difference.

Lemme put on my Bear Pit Hat

1 sec

MIL or MOA?

Now granted, I am old, fat, partially blind, never served in the "sandbox" nor train in any "Tier 1" units and I tend to favor my AK over the AR (its got the magnifier!), but I'd say learn to zero at 100, and learn your holds and learn to fucking send it.

But...but....but MUH BDC!!!!

Plus the fact you are struggling over 0.2 or 0.3 AT 100(63) YARDS!!!


(1)Go to the range, Put your dumbass BDC on the target at 100 yards. Fire 5 shots (pick one and ONLY one of your ammo selections)
(2)Now, take the second ammo selection. put your dumbass BDC on the target (pro tip--aim at the same point) and fire 5 shots.
(3)Wait for the range officer to call a cease fire (if shooting alone--thats YOU!)
(4)Pick up a tape measure.
(5)Walk to the target
(6)Measure the vertical distance between the groups assuming you haven't hamfisted some 6MOA group with your booger hook.

(7)Then pull the caps off your scope. Get the instruction manual as well. Figure out if it is MOA or MIL. Also figure out the subtensions in your crosshair.
(8)Google MOA or MILs to Inches and 100 yards and do mafs
(9)Now using that magnificient pience of warfighting kit, MEASURE THE DISTANCE IN THE SCOPE.
Your answer should match. If it doesn't go back to 2nd grade and learn basic math
(10) You passed basic math. Now take the number from step 8 and 9. Take that number and divide it by the value of 1 click. (be careful--it could be 0.1, 0.25, or even 0.5!--if division is hard, multiply by 10, 4 or 2)
(11) You now have your offset. Notice, we did not zero the rifle. We just looked at the POI of the groups.
(12) Bonus exercise: 15 points if you can explain why your BDC won't work at long distance for 55gr
(13) who the fuck has a 63 yard range?

Goddamn Doc. You should get some kind of award for this. Seriously.

 

[hafejd30]

It’s a fighting rifle!!

 

[Precision Underground]

Y’all are all going to hell lol

 

[hlee]

MPBR will allow for effective hits on target from much further than you’ll be able to justify for a defensive rifle. No BDC and no dialing for distance necessary.

 

[wade2big]

Don't be poors and just shoot 77gr ammo. That's what I do. Having multiple zeros and zeroing at 63 yards to match a BDC is stupid. BDCs are stupid to begin with. This isn't the 80s.

I’ll disagree with the BDC being stupid. It has it’s place and tweaking the elevation a bit can have a man on target with effective hits out a long ways. It’s not necessarily a “precision” tool but works well to 500 yards on targets far smaller than mansize. For semi auto’s and deer guns out to reasonable distances, they work well. Beyond that, not so much.

 

[_Windrider_]

I’ll disagree with the BDC being stupid. It has it’s place and tweaking the elevation a bit can have a man on target with effective hits out a long ways. It’s not necessarily a “precision” tool but works well to 500 yards on targets far smaller than mansize. For semi auto’s and deer guns out to reasonable distances, they work well. Beyond that, not so much.

BDC is fine for the round it’s designed for. But doing what’s going on here is more trouble than it’s worth.

 

[hafejd30]

Two different rounds, no problem

You’re welcome…

 

[gonzaga]

Questions use ? marks....

I personally would use the same load in the rifle in question.
Like others have said shoot the loads, measure the difference and go from there.

 

[Keith E.]

Thank you! Makes sense.



I know how to use mil reticle and mil turrets. This is a fighting rifle and I want to retain BDC for agility.

With me not being familiar with OPSEC procedures in your AO, I'll make this as sterile as possible.

Welcome to the Forum.

Keith

 

[2aBaC̶a̶]

what scope? Im having trouble understanding how a BDC lines up exactly with 2 different loads?

 

[wade2big]

what scope? Im having trouble understanding how a BDC lines up exactly with 2 different loads?

You must not have played around with BDC scopes. A scope with a 556 bdc will line up nicely with 55gr - 77gr and even across different barrel lengths. Fudge the zero a a few clicks one way or another and practical hits are easy to do out to 500 yards or so. While it may not be dead nuts, you can be within a few inches high or low all the way out.

I like to line up the 300 yard hold fairly close and let everything else line up as it does. If you aren’t walking around with a rangefinder all the time, being close enough is close enough because even if something lines up perfectly, the man judging distance will probably be off.

 

[MTCutlass]

Sorry, somewhat of a newbie. I have a similar question but in a slightly different context. I am using a scope with BDC markings.

i have a 300win mag loaded with 200gr eld-x for elk hunting, Zero range is at 100 yards. I also use 150gr norma whitetail when going for deer or long range practice, When i shoot the norma, i am 2.00-2.25" inches high at 100 yards. How would i calculate what the actual zero (zero range) is for the 150gr loads? (knowing the zero would be something over 100 yards and less than 300ish yards.

Why i am asking. I use the strelok pro app. If i have everything in for the 200gr at 100yd zero range thats great. If i can calculate the theoretical zero range for the 150gr loads (and of course some practice for verification). I can switch the load in strelok and in theory not loose the zero for the 200gr bullet. All that i would need is to "change the load" /round. and then change the zero on the scope (in the app) to reflect the zero range for each.

 

[Gil P.]

Rezero your scope 2 - 2 1/4 MOA for the lighter loads.

Try and get a scope without BDC that has reticle and turrets that use the same adjustment type. mil/mil, or MOA/MOA.

It will make your life a lot easier.

 

[6.5SH]

Sorry, somewhat of a newbie. I have a similar question but in a slightly different context. I am using a scope with BDC markings.

i have a 300win mag loaded with 200gr eld-x for elk hunting, Zero range is at 100 yards. I also use 150gr norma whitetail when going for deer or long range practice, When i shoot the norma, i am 2.00-2.25" inches high at 100 yards. How would i calculate what the actual zero (zero range) is for the 150gr loads? (knowing the zero would be something over 100 yards and less than 300ish yards.

Why i am asking. I use the strelok pro app. If i have everything in for the 200gr at 100yd zero range thats great. If i can calculate the theoretical zero range for the 150gr loads (and of course some practice for verification). I can switch the load in strelok and in theory not loose the zero for the 200gr bullet. All that i would need is to "change the load" /round. and then change the zero on the scope (in the app) to reflect the zero range for each.

This is what the "Zero offset" function in Strelok is for. Under the cartridge screen for the ammo you are not zeroed for enter +/- whatever the difference is in point of impact. +2.0 MOA Vertical in your scenario mentioned.

The advice given to zero with the faster/flatter shooting ammo is generally the better advice if using a zero stop. With a BDC it can vary, by adjusting Strelok for both scenarios (POI lower and higher) you can figure out which is the better compromise.