I am one who always wants full penetration (hole in-hole out) and over the years have found that certain things make this goal diffecult.
First is to use too light a bullet. The 140 grain bullet in the .284 caliber is a mid-range, bordering on a light-for-caliber bullet weight. Second is excess velosity. In my experience any velosity much above 3000 fps invites underpenetration (mostly enough to kill well, but may not exit). In this case the short range and high initial velosity meant a striking speed very near that level. A lightly constructed bullet can make penetration iffy even with proper velosity and weight. In this case the bonded bullet did NOT have this handicap.
Due to the high velosity, close range and light bullet.....I believe that 1 out of 5 or 6 bullets not exiting was pretty much what to expect. The bullet performed perfectly....as well as could be expected. If that same shot were taken (with a similar designed bullet) with say a 160 grain bullet at 2850-2900 fps I'd expect that a pass through would be almost guaranteed (bullets do strange things so no combination will ALWAYS work).
The design of the bullet is not the problem. As some others have pointed out, even the "solid" bullets fail to exit when velosities are driven to extreem levels. In fact, the tendancy of most to try to shoot the lightest possible bullet at the highest possible speed when using the "solids" (alphabet bullets) makes a pass througb possibly MORE likely at extreemly close range.
I really like the bonded bullets in general (Trophy Bear Claws and A-Frames are favorites) and this is Text book performance. As to the mono-metal "solids" I place them in the same class as steel shot in shotguns.....a gimic created by anti-hunting groups to hurt our sport.
