External Ballistics for Practical Rifle

The most important element of practical rifle shooting can be summed up in one sentence: You have to know where your rifle shoots.

This truism was illustrated for me a few weeks ago at the Tidewater 3-gun match.  Somehow, between the Topton team match and Tidewater, the zero on my rifle shifted about 3MOA low and left.  Normally I can blow through 200-yard Flash Targets with barely a care, but Sunday I was missing them left and right.  Well, mostly left…

Anyhow, this is a problem I see quite a bit.  A lot of shooters never have the chance to shoot a carbine out past 50 yards, and these are the shooters who struggle mighty with 200-plus-yard steel.  They don’t know where their rifle shoots.

So, whenever I get a new rifle or a new load, I like to run a dope table for it.  It’s easy to do, and it will save you a lot of heartache and dropped point on those long range stages.

You’ll need your rifle, ammo, a place to shoot (at least 100 yards, and 300+ is even better), and a stack of targets.  You don’t need to go all crazy elaborate with the targets – I use 3×5″ index cards stapled to sheets of scrap cardboard.

First things first, throw a target up at your preferred zero distance.  I zero my 3gun rifle at 100 yards, and my defensive rifle at 50.  Shoot at least a 3-round group, adjust your sights as appropriate, and repeat.  I prefer to do all my zeroing from supported prone, but there’s probably nothing wrong with establishing your zero from the bench.  Just don’t make a habit of it, and be sure to wash your hands afterwards.  😉

Okay, now you have a zeroed rifle.  Now it’s time to figure out your holdover at some different distances, from different positions.  I do this by shooting 10-round groups at different distances.  The distances that you shoot at are up to you and your type of shooting, but some suggestions are in the table below:

  • Prone – 50, 100, 150, 200, 300, and 400 yards.
  • Standing – 15, 25, 50, 75, and 100 yards.  I’d stretch it out to 150-200, except that I just can’t hold an offhand group that far out…
  • Supported offhand: 50, 75, 100, 150, and 200 yards.  I use a VTAC barricade or something similar as a rest.
  • Rollover prone/reverse rollover prone: 25, 50, and 100 yards.

For a given position, I set up a target at each distance and shoot the groups in a single string.  Then I measure the holdover/hold-off and note it in my shooting journal.  I frequently shoot different positions on different practice days, as a warm-up – prone one day, offhand the next, etc.

That’s the end goal of the zeroing process – to collect enough data that you’ll know exactly where to hold to hit a given target, no matter the circumstances or conditions.  Once you have that, you’re one step closer to mastery.

– Chris


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s