Norwegian Association of Hunters and Anglers’ test hunter project – an evaluation of killing efficiency for different shot types
Summary
Due to its toxicity, Norway imposed a general ban on hunting with lead shot from 1 January 2005. Since lead has long been the most common form of shotgun ammunition used in hunting, this ban has necessitated an evaluation of the killing efficiency of non-toxic alternatives now available to Norwegian hunters. In the Norwegian Association of Hunters and Anglers’ test hunter project, the killing characteristics of different ammunition substances were tested in the field by hunters on a number of game birds and mammals. All shot substances tested had killing efficiencies close to 100% for game mammals, which indicates that all alternatives tested were satisfactory for hunting game mammals such as red fox, roe deer and mountain hare. Normally, such game mammals are shot in situations where they are relatively slow-moving or standing still, with large vital areas that are relatively easy to hit. These results effectively dispel the notion held by many hunters that steel shot in particular is a poor alternative for hunting these species. For bird species, we also see that non-toxic shot types have similar killing efficiencies relative to lead shot, providing the proper shot sizes are utilized. For willow and rock ptarmigan (for which we had a large sample size for a specific species group), bismuth No. 6 and 7, Steel No. 2 and Hevi-Shot No. 5 were equivalent to lead in their killing efficiency, while Steel No. 4 and possibly No. 3 were also good alternatives. Although our sample size for wood pigeons was somewhat limited (n = 145), it appears that steel shot 5-7 and bismuth 5-7 were the most effective ammunition types. For forest grouse, bismuth No. 5 and 7, Tungsten-Matrix No. 5, and Steel No. 5 (and possibly Steel No. 3) were effective loads. For water birds, we found that Hevi-Shot No. 4, Tungsten-Matrix No. 1 and 2, along with bismuth No. 2, 4 and 5 and Steel No. 5 were performed satisfactorily. Since grouse and water birds vary greatly in size, hunters will naturally have to choose larger shot sizes for larger birds and the converse for smaller birds. Of course, there are also other factors in addition to killing efficiency which hunters must take into account when selecting ammunition. For example, hard shot types such as Hevi-Shot and steel ricochet more than the other alternatives, and should therefore not be used in areas with a preponderance of exposed rock surfaces. Steel shot is also problematic for the lumber industry due to damage to saws, and may be locally banned by some forest owners, as is the case in Denmark. In addition, different shot substances produce varying shot patterns with different weapons. Therefore, hunters should test their guns with different cartridges on paper targets before going afield in order to determine which loads perform best for them. Of course, hunters will always have to select the shot size which yields optimum results for a given game species. If hunters use ammunition composed of different substances for different purposes, it is important that they understand differences in ballistics associated with these and adapt their shooting accordingly. We are confident that experience and training over time will ensure that hunters both old and new will be equally proficient in humanely killing game as they were before the lead shot ban was imposed. For most game species, we demonstrated a negative correlation between killing efficiency and shooting distances. In controlled experiments using stationary subjects, the literature indicates that killing efficiency is stable up to 35 meters independent of the shot substance used. Thus, the ability of shooters to hit game apparently decreased as distance increased in our study. Since different shot types have different weights and velocities, these will effect deflection angles (leading distance) as well as shot patterns produced by different weapons. As such, reduced killing power is also an indirect result of the substance shot is composed of.