Shotgun Patterning

What is it and why it’s important

by Craig Endicott, Northeast Region Wildlife Supervisor

There are a lot of differing opinions about what works and what doesn’t work when it comes to nontoxic shot loads and their effectiveness for waterfowl hunting. Hunters don’t want to have to get a degree in physics to understand why this or that works, they just want to know what does work!

Well, there’s no getting around it, if you really want to know what your gun/load/choke combo is capable of, then you’ll need to pattern test it to find out. It isn’t a complicated process, but it does take some time and effort.

Of course, once you’ve determined the best load/choke combo for your type of hunting, the next step is to get plenty of pre-season wing-shooting practice at clay targets that simulate the kind of shots you’ll take while hunting. Shooting practice is important to effectively bag birds and reduce crippling. After all, if you can’t put the pattern on the front end of the duck then little else matters!

Why should I pattern test my shotgun?

Patterning your shotgun provides valuable information on the performance of your gun/load/choke combo that will allow you to make informed choices on your load, choke and pellet selections to match your particular hunting/shooting situation. Ultimately, patterning and tailoring your combo will improve your effectiveness as a hunter by reducing the number of shots you’ll need to get your birds and reduce crippling in the process.

Hunting time and opportunities at game are too precious to just go with an in-the-field trial-and-error method. Pattern testing, if done properly, will allow you to take the guesswork out of selecting an effective combo that fits your hunting/shooting situation.

How do I pattern test my shotgun?

1. Find a location that has an adequate and safe back-fall area. Don’t forget, you’ll want to bring both ear and eye protection.
2. Set up a pattern board so you can attach the pattern sheets. One quick and easy set up is two posts, set in the ground about four feet apart, and a 4-foot x 4-foot backboard of cardboard, thin plywood or black particle board attached with wire or wire ties.
3. Get some 40-inch x 40-inch (minimum) sheets of paper or cardboard. Try to locate 48-inch wide rolls of white paper at industrial supply or paper warehouses. It also saves time at the range if you precut this paper into pattern sheets.
4. Measure off your maximum shooting distance from muzzle to target with a measuring tape.
5. Attach a blank pattern sheet (a staple gun is handy) to the pattern board and fire one shot at the sheet. Remove the pattern sheet and repeat the process. You don’t need to shoot these patterns from a bench, just shoot at the center of the sheet to get them on the paper.
6. Shoot a minimum of three patterns for an average and five is better.
7. After shooting, draw a 30-inch diameter circle using a 15-inch string and pencil or a yard stick with holes 15 inches apart to scribe a circle that encompasses the densest portion of the pattern.
8. Count the pellet strikes inside or on the 30-inch circle and average the pattern count. You can calculate a pattern percentage if you like, but you don’t need to.

How do I know if my pattern is effective?

In order for a pattern to be effective it must possess sufficient pattern density to reliably hit the vital areas (brain, spinal cord, heart or lungs) of the target bird and contain pellets capable of delivering adequate energy to penetrate those vitals areas. Of course, you’ll want to compare your combo’s pattern numbers against reliable information to assess its effectiveness.

To date, the largest set of empirically tested lethality data on waterfowl and upland game birds is analyzed and presented in Tom Roster’s Cooperative North American Shotgunning Education Program (CONSEP) 2006 Nontoxic Shot Lethality Table (Copyright 2006 by Tom Roster). The table is Mr. Roster’s analysis of extensive terminal ballistics data derived from over 23,000 one-shot kills on waterfowl and upland birds and it provides a wealth of information useful to hunters trying to sort through the myriad of nontoxic shot loads available today. It is a no-nonsense approach at establishing the most effective shot sizes, minimum load weights and minimum pattern counts necessary for clean kills on various waterfowl and upland game birds.

What’s the average pattern count your combo put in the 30-inch circle at your maximum shooting distance?

Refer to Roster’s CONSEP 2006 Nontoxic Shot Lethality Table in the printed copy of the Waterfowl Guide and see if your combo’s pattern numbers meet or exceeded the minimum pattern count listed for your type of hunting. If they do, and you are using one of the appropriate shot sizes listed for the bird size and you keep your shots within the range of the activity, then you are good to go. You can feel confident that any duck of that size and at that distance or closer will be in the bag if you do your part and put the pattern on the front end of the duck!