NO TRUE ZERO

DON’T BE A BA­SIC BITCH — MAKE YOUR ZERO PER­SONAL

Recoil - - Contents - STORY AND PHO­TOS BY CANDICE HORNER & DAVE MER­RILL

Don’t Be a Ba­sic Bitch — Make Your Zero Per­sonal

Ask some­one what the best zero is, and you’ll get a re­sponse based on per­sonal pref­er­ence, prior train­ing, and maybe in­di­vid­ual needs. If you’re in the mil­i­tary or a law en­force­ment agency, the dis­tance you zero may well be dic­tated by an of­fi­cial gov­ern­ment pub­li­ca­tion or crusty old train­ing of­fi­cer. Most of us aren’t so lim­ited by these re­stric­tions, so why do we re­vert back to stan­dards that don’t ap­ply?

The U.S. Mil­i­tary has hun­dreds of thou­sands of both ri­fles and peo­ple, usu­ally all us­ing sim­i­larly spec’d am­mu­ni­tion. They can get away with gen­er­al­ized ze­ros. And it’s ben­e­fi­cial for them to keep firearms train­ing stan­dard­ized. But if you don’t have to be ba­sic, you shouldn’t be.

In the sim­plest terms, a zero is the ad­just­ing of the sights/op­tic so your point of aim matches your point of im­pact at a spe­cific dis­tance. This con­ver­gence is the in­ter­sec­tion be­tween your line of sight and bul­let tra­jec­tory. Bul­lets aren’t laser beams like in the movies, and are sub­ject

to grav­ity. If your bore and sight lines were both per­fectly par­al­lel, their paths would never cross, and thus no zero could be ob­tained.

Many pre­vail­ing ze­ros have two con­ver­gence points that in­ter­sect the line of sight, giv­ing you both a near zero and a far zero. Com­monly, these are writ­ten as

“50/200” or “25/300,” though they vir­tu­ally never ac­tu­ally print on tar­gets ex­actly in that man­ner in the real world. This type of zero is a short­cut so­lu­tion that doesn’t max­i­mize your ri­fle’s ca­pa­bil­i­ties.

For most types of shoot­ing, we should strive to have the long­est Max­i­mum Point Blank Range (MPBR) pos­si­ble. In pop­u­lar cul­ture “point blank” means a shot from an es­pe­cially close dis­tance; throw max­i­mum into the term and it means the far­thest you can shoot and hit your tar­get with­out hav­ing to ad­just your sights or hold. You can suc­cess­fully think of your MPBR as a bal­lis­tic tube of Point-Click-Kill.

THE START­ING POINT

Your ze­ro­ing dis­tance should be task-ori­ented. To de­ter­mine the best zero, an­swer the fol­low­ing ques­tions:

What is your in­tended tar­get?

How far do you plan to shoot?

What op­tic, if any, is on your ri­fle?

In ad­di­tion to sev­eral vari­ables that go into ri­fle shoot­ing, your an­swers to those ques­tions can af­fect what zero you should ac­tu­ally be us­ing.

The size of the in­tended tar­get and your an­tic­i­pated range of en­gage­ment de­ter­mine your re­quired pre­ci­sion stan­dard. If you want to shoot the lit­eral broad­side of a barn at 10 feet — your zero doesn’t mat­ter at all. If you want the abil­ity to make a head shot at 425 yards or snag a suc­cess­ful hit on a par­tially ob­scured tar­get closer in, hav­ing a solid zero and know­ing your dope mat­ters. So. Much. More. It shouldn’t come as a shock to any­one that most things don’t just stand there and let you shoot at them.

The larger the in­tended tar­get, the more lee­way you have in your MPBR. If you’re a sol­dier on the streets of Afghanistan, a re­quired 400-yard hit is in­fin­itely more likely than if you’re a cop on the beat. If you’re a hunter, your MPBR has to mea­sure within the kill zone of the an­i­mal. Ul­ti­mately, what you’re try­ing to fig­ure out is how far you can shoot your ri­fle and make a hit while still main­tain­ing the same point of aim.

You can get the most out of your weapon setup by run­ning a zero that makes sense for your op­tic. A red-dot sight with no mag­ni­fi­ca­tion has sev­eral ben­e­fits, but draw­backs oc­cur when shoot­ing at fur­ther dis­tances. De­pend­ing on what zero you use with a red-dot, you could be hold­ing a lot of space be­tween the dot and the top of your tar­get.

Red-dot op­tics aren’t used for pre­ci­sion long-range shoot­ing, so run­ning an MPBR zero is ben­e­fi­cial.

For pre­ci­sion shoot­ing, a 100-yard zero is hard to beat. Hav­ing the ri­fle zeroed at 100 and di­al­ing or us­ing the MOA or MRAD holdovers is pre­cise and pre­dictable. With a 100-yard zero, there isn’t an­other point of con­ver­gence. This is ben­e­fi­cial for long-range shoot­ing be­cause the shooter doesn’t have to prob­lem solve whether or not to hold un­der or over. The cor­rec­tion for ev­ery shot is go­ing to re­quire the shooter to ei­ther dial up or hold over.

These days, most scopes have more than enough of el­e­va­tion ad­just­ment. But you may run into a few scopes that ei­ther don’t have el­e­va­tion tur­rets in­tended to be ad­justed on the fly, or they may not have enough clicks, or you may not have enough time to dial. Once again, an MPBR zero is ideal. Max­i­mum MPBR gets the most out of your ri­fle from your po­si­tion to the tar­get and on­ward.

Once you sur­pass the reach of your MPBR, it’s im­per­a­tive to know your data at ev­ery dis­tance. With a red-dot, this means know­ing your holdover, and with a mag­ni­fied op­tic, ei­ther the same or how much to dial.

The ca­pa­bil­i­ties of your ri­fle setup are as unique as a fin­ger­print. No two ri­fles are ex­actly the same, and they never will be thanks to small vari­ances dur­ing the build process, and the fact that ev­ery bul­let that goes down the bar­rel per­ma­nently changes the ri­fle. This is why slap­ping a 50/200-yard zero on it isn’t good enough. So how do we fig­ure it out?

BAL­LIS­TIC CALCULATORS — THE CRYS­TAL BALL OF LON­GRANGE MATH

Us­ing a bal­lis­tic cal­cu­la­tor to de­ter­mine the best zero for your weapon sys­tem is like hav­ing an­swers to the test. We’re big fans of bal­lis­tic en­gines; no longer do we have to rely on guess­work from tra­jec­tory charts on­line nor old mil­i­tary man­u­als. In­stead, we can tai­lor a zero to what we want the ri­fle to do.

Thirty years ago the idea of us­ing a bal­lis­tic cal­cu­la­tor to de­ter­mine your best zero was prob­a­bly a non­starter for most; it in­volved a lot of books, spe­cial­ized equip­ment, and maybe a pro­trac­tor or graph­ing cal­cu­la­tor. Bal­lis­tics was a mys­tery, rel­e­gated to the most nerdy of long-range shoot­ers. This is no longer the case, and if you have an In­ter­net con­nec­tion you have free ac­cess to some of the best bal­lis­tic calculators in the world. Right in your pocket at this mo­ment is likely a com­puter more pow­er­ful than any used by the high­est-end univer­sity a decade ago. By all means look at cute cat pho­tos and porn with it, but uti­lize that pro­ces­sor for some cal­cu­la­tions too.

If you open up a bal­lis­tic cal­cu­la­tor, you’ll find sev­eral im­por­tant vari­ables at play — and they all af­fect where your pro­jec­tile ends up downrange. Since any mi­nor el­e­ment or de­vi­a­tion ex­po­nen­tially ex­pands with range, the far­ther you shoot and the tighter the pre­ci­sion stan­dard, the more each of these com­po­nents mat­ter.

Stuck at a range that only al­lows you to shoot 25 yards? Use a cal­cu­la­tor to show your off­set. At a long range and un­sure of your hold? Use a cal­cu­la­tor to give it to you. Bal­lis­tic calculators aren’t just for sim­ple holdovers ei­ther; with most of them you can save in­di­vid­ual data from a given gun and am­mu­ni­tion com­bi­na­tion for easy ac­cess later. Some apps like Strelok Pro have op­tions where you can dis­play the same reticle in your scope on the screen, and lit­er­ally show you where to hold to make your hit. Many range find­ers and weather me­ters will in­ter­face with your stand­alone or in-phone bal­lis­tic app to pro­vide you with the best and most up-to-date in­for­ma­tion.

You can’t rely on the listed ve­loc­ity on the side of the ammo box if you want your cal­cu­la­tions to be any­where close to re­al­ity. In­vari­ably those read­ings were taken at ideal sce­nar­ios — per­fect weather, longer bar­rels, etc. The ve­loc­ity of a given load is

in­cred­i­bly sub­ject to nu­ances of your in­di­vid­ual ri­fle. Not only is bar­rel length a com­po­nent, but also the cut of the cham­ber, and even minute dif­fer­ences in bar­rels on oth­er­wise iden­ti­cal guns. The best way to de­ter­mine the ac­tual muz­zle ve­loc­ity is to use a good chrono­graph such as a Mag­neto Speed or LabRadar. If you don’t have a chrono­graph or a friend with one, the next best thing would be to find some­one who has in­de­pen­dently tested the rounds in a sim­i­lar setup to what you’re us­ing. Im­per­fect for sure, but bet­ter than go­ing by the box.

FIND­ING YOUR MPBR

If you want to be able to hold cen­ter of your tar­get and hit, use tech­nol­ogy to fig­ure out what your zero should be. Here’s an ex­am­ple we worked up:

We used the Shooter phone app by Kennedy De­vel­op­ment Group LLC. We in­put all the data for our ri­fle, ammo, and scope com­bi­na­tion. We de­ter­mined the size of the tar­get we planned to shoot (10 inches). From there, noth­ing changed ex­cept the ze­ro­ing dis­tance un­til find­ing the MPBR.

Since our in­tended tar­get is 10 inches round, if we held dead cen­ter, we would have a 5-inch ra­dius all the way around our cir­cu­lar tar­get. To re­late this to the drop of the bul­let, we can only have plus or mi­nus 5 inches of drop in our data if we want to make a hit with­out ad­just­ment.

We tried the stan­dard 100-, 200-, and 300-yard ze­ros. The data showed our bul­let’s path would stay within our tar­get size:

Just over 225 yards with a 100yard zero

Out to 274 yards with a 200-yard zero At a mere 126 yards with a 300-yard zero the tra­jec­tory is out of our al­lowed ra­dius

Af­ter run­ning the data for the stan­dard ze­ro­ing dis­tances, we ad­justed the zero dis­tance un­til the high­est point of the bul­let’s path was at 5 inches. Do­ing this al­lowed us to use the pro­jec­tile’s tra­jec­tory to its max­i­mum ca­pa­bil­ity, as re­lated to the size of our in­tended tar­get. With the very spe­cific 292-yard zero for this ri­fle/ammo combo, our MPBR is around 340 yards. We should be able to hold cen­ter on a 10-inch tar­get, out to 340 yards — and hit.

YOUR ZERO IS CON­STANTLY CHANG­ING

We’re not even talk­ing about drop­ping your ri­fle. If you zero at sea level in the North Car­olina sum­mer, and head over to the peaks of Colorado in the win­ter, your zero will change. At­mo­spheric pres­sure, tem­per­a­ture, el­e­va­tion, and more will change your point of im­pact.

There’s an EOTech joke in here, and we’ll ad­dress it be­cause we know you’re think­ing it: It doesn’t mat­ter what op­tic you use, if you have a large tem­per­a­ture change your zero

ab­so­lutely will shift. Know how to zero your ri­fle and check your zero be­fore tak­ing any im­por­tant shots.

THAT BDC DOESN’T MEAN WHAT YOU THINK IT MEANS

Just as with a gen­er­al­ized zero, the mil­i­tary can get away with a Bul­let Drop Com­pen­sator (BDC). A BDC has lines in the reticle it­self for el­e­va­tion holds at given dis­tances for a par­tic­u­lar cal­iber. Ex­cept it’s not. Not un­less you’re us­ing an iden­ti­cal ammo/ri­fle com­bi­na­tion and are in the same ex­act en­vi­ron­men­tal con­di­tions the BDC was de­signed for and tested in.

You can find a good ex­am­ple of a BDC in this very is­sue — head on over to check out the U.S. Op­tics SR-85 with Plumb Reticle. Also note that it’s setup for (1) cal­iber, in (1) given bar­rel twist with (1) kind of am­mu­ni­tion. A des­ig­nated marks­man in the mil­i­tary can get away with that — you can and should do bet­ter.

Sev­eral op­tics man­u­fac­tures have been mar­ket­ing BDC ret­i­cles to the gen­eral pub­lic as a so­lu­tion to en­gage tar­gets quicker with­out hav­ing to re­mem­ber your Mil or MOA holds. There are also cal­iber-ded­i­cated scope tur­rets to ease the thought process of lon­grange shoot­ing. But, just as we al­ready men­tioned, your zero changes with your en­vi­ron­ment — and your gun and am­mu­ni­tion com­bi­na­tion isn’t the same as the man­u­fac­turer.

Don’t rely on these short­cuts when your shots mat­ter.

If you’re go­ing to an area with a dif­fer­ent den­sity al­ti­tude, first con­firm your zero and then ei­ther use a bal­lis­tic en­gine that will up­date the en­vi­ron­men­tal con­di­tions or true your ri­fle data for ev­ery dis­tance you plan to shoot.

But all isn’t lost, once you ac­cept that the sta­dia lines of the BDC are just lines, you can use them as points of ref­er­ence. For ex­am­ple, if your hold for 400 yards isn’t ex­actly cen­ter, but in­stead the bot­tom of a 10-inch plate, you know that’s your hold.

If your ac­cu­racy stan­dard is no greater than minute-of-deer at 80 yards, that ran­dom BDC made for a 7.62N on your .30-30 will prob­a­bly work.

LOOSE ROUNDS

It should be said that re­gard­less of what bal­lis­tic en­gine you use, you’re go­ing to want to con­firm those holds are cor­rect by ac­tu­ally shoot­ing rounds down range. Noth­ing will give you more con­fi­dence in your data than mak­ing a suc­cess­ful hit.

Ini­tially we thought we would name this piece “Re­think­ing the Zero,” but it wasn’t ac­cu­rate — in re­al­ity we’re ask­ing you to ac­tu­ally think about how and why you zero in the first place. With nu­mer­ous bal­lis­tic en­gines and boat­loads of data at your fin­ger­tips, there’s lit­tle ex­cuse not to spend a mod­icum of time and con­sid­er­a­tion on your zero.

If you’re the type that thinks a rough zero is good enough and turn­ing dol­lars into noise is all you want — you do you. But if you want to max­i­mize the ca­pa­bil­i­ties of your unique ri­fle, op­tic, and am­mu­ni­tion setup use the tools at your dis­posal.

This ex­am­ple was gath­ered with a 6.5 Creed­moor us­ing one spe­cific am­mu­ni­tion. Your ri­fle/ammo com­bi­na­tion will be dif­fer­ent — so treat it as such.

Holdovers are a quick, dirty, and ef­fec­tive way to save you the time of di­al­ing el­e­va­tion. Learn your holds, and what they look like at range.

An­tic­i­pate a small tar­get? Your bal­lis­tic tube of max­i­mum point blank range is go­ing to be shorter.

If your sight line and bore line were par­al­lel, you’d never be able to ob­tain a real zero.

Ev­ery­thing you need to zero, and a bunch of sh*t you don’t.

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