5 Ways to Increase Arrow Penetration

By author of Brow Tines and Backstrap

A bow only works if it can push a broadhead through the vitals. Here are five ways to get the most out of your setup.

When I first started bowhunting, the legal minimum draw weight was 40 pounds. Draw-weight restrictions have long since been lifted here, as well as in many other areas. Today’s top-notch equipment allows a bowhunter more ways than brute draw weight to get the penetration required for a lethal shot.

Anyone shooting a light draw-weight or short draw-length bow should seize every opportunity available to increase the penetration potential of his or her hunting setup. But extra “oomph” is never a bad thing, even if you’re shooting a big-boy setup. These five changes can help you gain just that.

Bowhunter in treestand

Shoot A Heavier Arrow Shaft

Bowhunters fuss a lot over kinetic energy, as it’s no doubt an important figure. But for penetration purposes, momentum is arguably more important. That’s why a 55-pound recurve might lob a 600-grain arrow at softball speeds, but with a sharp broadhead, that arrow will zip through a deer no problem. If your carbon arrow shafts weigh, say, 7 or so grains per inch, consider swapping to something that weighs 9 or 10 grains per inch.

Shoot the Right Spine

I’m amazed at how many bowhunters ignore the spine of their arrows. Arrow spine is, basically, the stiffness of your arrow. The bigger the number (say, 400 vs. 340), the more flexible the arrow shaft. A spine that’s too soft for your bow will keep right on flexing in flight, which of course can impede penetration (and in extreme examples, damage your bow because the arrow isn’t absorbing enough of the bow’s energy at the shot).

The Proof

My wife, Michelle, has a 24-inch draw length and shoots 50 pounds. Those are pretty puny specs. Yet, she kills deer every season. Last year, she shot a doe through both shoulders at 30 yards. Her setup was a heavy Easton Axis 500 arrow tipped with a sharp Montec.

A good pro shop or arrow manufacturer can tell you the best spine for your setup. Arrow spine recommendations change with varying draw weights, draw lengths and cam designs.  

Shoot a Heavier Broadhead

The arrow shaft isn’t the only place to increase weight. It’s a safe bet that the average bowhunter uses 100-grain field tips and broadheads. But 125-grain points are readily available. Switching to a heavier broadhead not only increases the total weight of your arrow for more momentum, but it also increases your arrow's Front of Center (FOC), which is the total weight of the arrow forward of the balance point. A little extra FOC (without going crazy) can help your arrow's penetration potential.

Shoot a Small-Diameter Arrow Shaft

There is a reason why Olympic archers shoot tiny-diameter arrow shafts. They’re more aerodynamic, and less affected by wind drag. That same principle applies to hunting shafts. A couple winters back, I tested the penetration potential of an Easton Injexion arrow shaft against a standard Easton carbon shaft (Flatline). Both shafts were the same length, although the Injexion shaft was slightly heavier. It routinely out-penetrated the carbon shaft by 6 to 8 inches at 40 yards in a 3D target. That’s huge.

Micro-diameter shafts used to require specialized inserts and thus, specialized broadheads. So they haven’t quite caught the bowhunting world afire. But, there are products on the market to fix that. These outserts from Clean-Shot Archery allow bowhunters to use micro-diameter shafts in conjunction with standard 8-32 thread broadheads. The outserts weigh 50 grains, so you’re also adding substantial weight up front.

Shoot a Cut-on-Contact Broadhead

Mechanical broadheads work very well – when they in fact work. I’ve sung the praises of mechanicals on turkeys quite a bit in the past. But this past spring, while bowhunting in Nebraska with Stephanie and Cally, I had not one but two mechanical broadhead failures that kept the arrows from passing through the birds. We’re talking broadside 20-pound turkeys at 10 yards with a 300-fps-plus bow. I recovered both birds, but only after making follow-up shots.

I’m not swearing off mechanicals forever. But I’m certainly more leery of them now. A good fixed-blade broadhead simply doesn’t fail. A cut-on-contact head, like my pet G5 Montecs (but also an NAP Hell Razor or Muzzy Phantom) cuts, well, on contact. They have the very least resistance of any broadhead style and so, as a rule, tend to penetrate best.