Can a Deer Jump the String? How Arrow Speed and Reaction Time Change the Shot

A deer can move before an arrow arrives. That does not mean the answer is to build the lightest, fastest arrow your bow can safely shoot.

I hunt with arrows that normally weigh between 490 and 515 grains. I know they are not the fastest arrows I could shoot. I also know exactly why I use them: they give me the penetration capability, broadhead control, bow behavior, and confidence I want inside the ranges where I hunt.

Deer reaction time still matters. On broadside shots past 20 yards, I often hold low, sometimes near the point where the front leg meets the body, when the deer’s posture and alertness support it. I base that hold on my verified trajectory and my complete arrow setup. It is not a universal aiming point for every hunter.

Speed matters. The issue is how much control we should give it when deer do not all react the same way, arrows lose speed in flight, and the same grains-per-pound number creates very different arrows for different hunters.

We need to separate measured arrow data from modeled deer movement, then put both back into the complete hunting shot. The evidence gives us useful limits, and those limits show where speed fits in the Everyday Arrow System.

What Bowhunters Mean by “Jumping the String”

A deer does not jump over the bowstring. It hears a sound, senses danger, and drops its body as it loads its legs to leave. That downward movement can take the chest and vital area below the point where the arrow was headed.

The phrase makes the event sound simple. The actual timeline is not:

1. The bow releases stored energy and produces sound.
2. The arrow leaves the bow, slows as it travels, and can produce its own sound.
3. Sound reaches the deer.
4. The deer detects the sound, decides it matters, and begins a physical reaction.
5. The deer may drop, turn, freeze, take a step, or barely move.
6. The arrow reaches the deer, or the place the deer occupied at release.

That chain is why a single reaction-time claim cannot predict every hunting shot. Speed changes one part of the timeline. It does not control the deer’s alertness, its first movement, or the direction it chooses.

How Much Time Does the Arrow Spend in Flight?

The simplest way to see the value of speed is to compare travel time. The table below divides distance by a constant arrow speed. It is a teaching comparison, not a trajectory prediction. Real arrows slow in flight, so actual flight time will normally be longer.

At 30 yards, the simplified difference between 260 and 300 fps is about 0.046 second. The difference can matter, but it cannot guarantee that one arrow produces a good hit and the other does not.

If you want to see where speed fits into the complete build, my Best Arrow Speed for Hunting analysis models 1,008 bow setups. This post has a different job: deciding what that speed means when the target can move.

What the American Hunter String-Jumping Model Shows

In “The Science of String Jumping,” Bill Winke described two 30-yard shots at alert bucks. After reviewing his video frame by frame, he reported that neither buck began dropping until the arrow was nearly 20 yards from the bow. He was shooting about 290 fps.

Winke then built a mathematical model. For a deer at 30 yards, he estimated that movement began 0.15 second after the bow fired. That delay included the time required for sound to reach the deer. His model produced about 14.8 inches of drop with a 260-fps arrow and 8.8 inches with a 300-fps arrow, a six-inch modeled difference.

I agree with the most useful part of his conclusion: read the deer, respect distance, and understand that speed can reduce the time available for movement. I do not agree that every hunter should turn that finding into an arrow near six grains per pound, or GPP, and let speed take priority over the rest of the system.

Six GPP Does Not Produce the Same Arrow for Every Hunter

Grains per pound divides total arrow weight by peak draw weight. It is useful for checking an arrow against a bow manufacturer’s minimum. It is not a complete hunting-arrow formula.

A 50-pound bow at a shorter draw length with a 300-grain arrow is not the same system as a 70-pound bow at a 30-inch draw with a 420-grain arrow. The 80-pound hunter reaches 480 grains at the same 6 GPP. All three may display the same ratio, but they will not produce the same launch speed, stored energy, momentum, trajectory, noise, or penetration capability.

I do not use one arbitrary weight or GPP number for every hunter. The best arrow is the one optimized for your bow, draw length, broadhead, hunting distance, sight plan, and the way you hunt. I created the Everyday Arrow Weight Formula and Arrow Planner to make that complete decision easier.

What Real Downrange Arrow Data Adds

The 2025 Arrow Ballistics Study from Precision Cut Archery adds two important pieces that simple launch-speed arguments can miss: arrows slow down, and different arrow configurations produce measurable differences in flight sound.

The selected configurations lost roughly 12 to 13 fps by 30 yards and about 24 to 25 fps by 60 yards. That confirms a basic point: launch speed is not impact speed. The study also found different deer-weighted sound levels among complete configurations.

But the study did not measure deer movement. It does not tell us that one of these arrows makes a deer drop a certain number of inches. It tells us that downrange speed and arrow sound are real variables. The deer still decides whether and how it reacts.

This also connects to vane choice. Steering, drag, clearance, rear weight, and sound all belong to the finished arrow. My Hunting Arrow Vanes guide explains why no single vane number should be pulled out of the complete configuration and treated as the whole answer.

Why the Fastest Arrow Is Not Automatically the Best Hunting Arrow

If we designed every arrow around the worst movement a deer might make, we would chase speed at the expense of everything else. That solves uncertainty by pretending only one variable matters.

• Speed shortens flight time. That is useful, especially as distance grows.
• Arrow mass can improve how efficiently the bow transfers stored energy. An extremely light arrow can leave more energy behind in bow movement, vibration, and noise instead of carrying it downrange.
• Momentum and structural strength help protect penetration capability. They do not guarantee penetration, because broadhead sharpness, arrow flight, alignment, angle, and anatomy still matter.
• Broadhead control matters. A fast arrow that does not tune, clear the bow, or steer the broadhead well is not an ethical shortcut.
• Trajectory matters to the hunter. If an arrow becomes too slow for the verified sight window, effective range shrinks and the deer has more time to move.

The goal is not the heaviest arrow you can launch or the fastest arrow you can assemble. The goal is the best balance your bow can deliver for your mission. The Bow Power Curve and Arrow Weight post explains why useful stored energy should be carried downrange instead of wasted. The Heavy vs. Light Hunting Arrows guide covers the full tradeoff between trajectory, speed, momentum, and penetration.

How I Manage Deer Reaction With a 490- to 515-Grain Arrow

My normal hunting arrows fall between 490 and 515 grains. I hunt primarily inside 30 yards. I know my bow, my actual speed, my broadhead flight, and where the arrow lands through the distance window I am willing to use.

On many broadside shots beyond 20 yards, I purposely aim lower. Depending on the deer’s posture and alertness, that can put my hold near the point where the front leg meets the body. If the deer drops to load its legs, that gives the arrow room to move into the chest instead of above it. If the deer stays put, my hold still needs to remain inside an ethical vital window.

I also avoid stretching the shot because my pin says I can. Inside 20 yards, the movement window is smaller. From 20 to 30, I pay close attention to posture and alertness. Past 30, the arrow has more time to slow and the deer has more time to change the shot. Longer shots require more proof from the hunter.

A Practical String-Jumping Shot Check

Before you release an arrow, make the decision in this order:

1. Read the deer. Is it relaxed, feeding, tense, looking at you, or already prepared to leave?
2. Read the distance. Do not use launch speed as if the arrow never slows. Know your verified pin or hold at that exact range.
3. Read the angle. Broadside, quartering, and elevated shots do not share one aiming point.
4. Read the opening. Branches, brush, and narrow lanes reduce your margin. A deer can also step into or out of that opening.
5. Use your system. Your arrow speed, weight, broadhead, bow noise, verified trajectory, and effective range must support the shot.
6. Let down when the variables stop lining up. No speed figure repairs a bad angle, an alert deer at the edge of your range, or a hold you have not practiced.

Use the ethical shot-placement guide to work through body angle, anatomy, and the path the arrow must take. My 25-yard bow-sight zero is one way I simplify the sight window I use most, but your verified hunting window may be different.

The Best Arrow Accounts for the Deer and the Rest of the System

A deer can move before an arrow arrives. A faster arrow can reduce that movement window. Those facts belong in the build.

They do not erase the rest of the arrow’s job.

I want enough speed to hold a useful trajectory through my hunting range. I also want the arrow to use my bow’s stored energy well, steer my broadhead, survive the hit, and give me the penetration capability the shot may require. Then I want a sight plan and aiming process that account for the animal in front of me.

That is the Everyday Arrow System: not a magic speed, a magic weight, or one GPP number for everyone. It is a complete arrow optimized for your bow and the way you hunt.

Sources, Calculations, and Data License

• Bill Winke, “The Science of String Jumping,” American Hunter, July 14, 2010. Figures above are summarized and clearly identified as Winke’s observations and model.
• Precision Cut Archery, 2025 Arrow Ballistics Study data, including the radar velocity summary, overall weighted sound-pressure levels, and deer-hearing filter.
• The simplified flight-time table was calculated by The Everyday Bow Hunter as distance divided by constant speed. It does not include aerodynamic slowdown and is labeled accordingly.

Precision Cut data attribution: Data source: Precision Cut Archery, 2025 Arrow Ballistics Study. Tables and explanatory labels adapted and selected by The Everyday Bow Hunter. Changes include formatting, selected comparisons, rounded presentation to the published precision, and explanatory labels. Precision Cut data and adaptations are licensed under CC BY-NC-SA 4.0.