Holdover, BDC Reticles, or Turret Dialing

There’s a new myth starting: Riflemen no longer have to deal with holdover thanks to BDC reticles and turret dialing.

BDC reticles provide sub-reticles that can be used to aim where your bullet strikes at various ranges. This eliminates the appearance of visual holdover but does nothing to change barrel holdover.

 

There’s a new myth starting. It says that riflemen no longer have to deal with holdover thanks to BDC reticles and turret dialing. Let’s nip this one in the bud, shall we?

In the shooting world, holdover is commonly understood to mean aiming over your target in order to hit it. It’s expressed as, “Man, you’d better hold over. He’s waaaay out there.” Back in the days of open-sighted muzzleloading rifles, it was called a “coarse” aim or “seeing a lot of post.” The more familiar phrase “Kentucky windage” refers to aiming into the wind to compensate for wind deflection, not holding over, but the concept is the same.

When scopes became commonplace shooters found it a lot easier to hold over because they could still clearly see their magnified target beneath the aiming point (crosshairs). The narrow, vertical line running down through the target made it easier to hold the proper sight picture left-to-right, too. “Put your vertical wire on its front leg and hold the horizontal wire just over its back” was common aiming advice.

 

For hundreds of years the way to hit a buck at long range was to hold your sights over its withers to compensate for bullet or arrow drop. This need to hold high doesn’t really change with BDC reticles or turret dialing—it just appears to.

 

DO BDC RETICLES AND TURRET DIALING REALLY ELIMINATE HOLDOVER?
The claim now is that turret dialing or selecting the correct sub-reticle on a BDC (Ballistic Drop Compensation) reticle enables hunters to hold dead-on. As a reader recently told me, “With laser rangefinders and BDC reticles, holdover is obsolete.” Well, he’s sort of right, depending on how you define the word “holdover.”

There’s visual (line-of-sight) holdover and barrel (axis-of-bore) holdover. BDC reticles, dialing turrets, hyper-velocity bullets, laser rangefinders, and the world’s most efficient VLD bullets can eliminate the need for visual holdover, but not barrel holdover. Regardless of your scope or sighting system, in the world of Newtonian physics, holdover remains necessary at any distance because gravity begins pulling bullets down the instant they leave the barrel. Once you think about it, this is one of those “duh” moments, but we get so enthralled with our gadgets that we sometimes don’t think that way. So, at the risk of belaboring the obvious, I will belabor the obvious . . . just to more accurately focus our shooting perceptions.

 

Turrets designed to dial for long-range shooting merely move the scope’s reticle down, forcing shooters to angle their barrels ever farther over the target to compensate for bullet drop. Visual holdover is eliminated, but not actual holdover. Swarovski’s superbly bright and consistent X5i dials 82 MOA elevation.

 

BELABORING THE OBVIOUS: BDC RETICLES DON’T ELIMINATE HOLDOVER
A barrel aimed perfectly level at a target 100 yards away will not put a bullet precisely on that target because gravity will pull the bullet below it. It doesn’t matter how fast the bullet flies or how ballistically efficient it is. It will land low because gravity pulls it at an accelerating velocity of 32 feet per second. So, unless that bullet is flying at the speed of light, it’s going to drop at least a trifle.

What might surprise you is how much that trifle is: Aimed dead-level at the bull’s-eye, a 140-grain bullet with a ballistic coefficient of .625 and muzzle velocity of 3,400 fps strikes 1.96 inches low at 100 yards. It’s 7.7 inches low at 200 yards and 17.66 inches down at 300 yards.

The need to offset this drop is partly why we have sights that stick up above our barrels. Those high front posts and elevated scope bases give us the room to angle our barrels up through our line-of-sight. This angle is so small that it’s tough to spot when aiming modern, high-velocity centerfires at typical hunting ranges, but it’s always there. Extreme-range shooters will often mount scopes with a 10- to 20-degree riser under the rear ring to angle barrels and extend scope turret adjustment range even more.

 

WHY BDC RETICLES AND TURRET DIALS MAKE HOLDOVER SEEM OBSOLETE
With visual and barrel holdover definitions clarified, we can more clearly understand what many shooters mean by “holdover is obsolete.” They mean the need for a visual holdover is obsolete. BDC reticles allow you to hold one of their many sub-reticles right where you want your bullets to land if you know the precise distance to the target (laser rangefinders handle this) and which sub-reticle corresponds to that distance.

Wind deflection must also be accounted for. If there aren’t precise windage reticles on the sub-reticle chosen, Kentucky windage must still be used. But the next time you select a long-range sub-reticle in a BDC scope, take time to notice where the central crosshair is hovering: over your target. You are still employing barrel holdover. You’re just able to do it more precisely with the sub-reticle by holding right where you want your bullet to land.

Arguably the most versatile BDC reticle is the Holland ART, Advanced Reticle Technology. Infinitely versatile, it works with any rifle, any cartridge, any bullet, anywhere.

 

Holland’s ART reticle uses sub-reticles spaced in MOA and numbered for easy recognition. Used in conjunction with a laser rangefinder and trajectory table in MOAs, selecting the correct aiming reticle is easy.

 

HOLDOVER, LIKE TAXES, STAYS WITH US, BDC RETICLES OR NOT
With a turret-dialing system, you dial your scope’s elevation turret to position the crosshairs for a dead-on hold. Both these systems, by the way, result in creating the same barrel holdover we’ve always used to hit distant targets. Until we start shooting guided missiles with their own power source, we’ll continue employing some form of holdover to make downrange hits.

 

For more from Ron Spomer, visit his website, ronspomeroutdoors.com, and be sure to subscribe to Sporting Classics for his features and rifle column.

 

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