Determining Loads With Bench-Rest Testing
After setting up the testing conditions, test a variety of loads by firing a series of three shots with each load. If possible, try a variety of bullet and powder combinations. The combination that gives you the best grouping on the target should be your selected hunting load.
Follow these guidelines when loading a powder charge.
- Usually firearms are most accurate at 70–90% of maximum load.
- A load less than that reduces velocity, causes a more rounded trajectory, and allows other variables, such as wind, to influence the shot.
- Greater loads burn partially and unreliably, diminishing accuracy without adding benefit.
- The ball with a patch generally accepts higher powder charges more safely than large conical bullets.
Refer to the owner's manual for your firearm's minimum and maximum loads. Also, some states require a minimum caliber for certain game. Be sure that you meet these regulations. To select a starting load:
- Start with half of the maximum load or…
- Load an amount of powder equal in grains to the firearm’s caliber.
Focus on accuracy factors to find the perfect load.
- Vary the tightness of the round-ball patch.
- Try different thicknesses and different patch materials.
- Examine spent patches for holes or charring that may indicate you need to use a different material or loading technique. Patches that failed usually are torn or blown apart. Patches that are charred were too thin and allowed gases through.
- Consider using tightly fitting conical bullets, which are often, but not always, more accurate.
- Keep your ignition system functions consistent.
- On in-line and percussion lock firearms, use the same brand of cap.
- On flintlock firearms, use the same way of fitting the flint and priming.
- Narrow down the best load combinations, and then try slight variations to see if any can be improved further.
- Analyze what may be the most consistent weaknesses to improve load performance.