gamestalker
member
I think one of the most debated topics of hunting weapons and bullets is based on velocity, bullet weight, and construction properties of the projectile it's self. My thoughts, and to some degree testing results, have been with the 7 mag. and .270 win. with the 7mm RM the center of my most recent pet cartridges. I was sitting here thinking of which bullet to try out this huntng season for mule deer using my 7mm RM with a lot emphasis on penetration and down range velocity, obviously.
I started with a 120 gr. standard Hornady PSP bullet @ 150 yds. down range @ a chronographed M.V. velocity of just under 3300 fps, it consistently and completely blows through a 1/2" piece of average grade plate steel. However, a bullet only 20 grains lighter at a velocity of nearly 3600 fps doesn't get through and barely fractured the opposit side. Both bullets are nearly identical in structure, I have sliced them in half from heel to tip and everything looks to be equal in jacket thickness less the 20 grains of weight in the 100 grain projectile. Considering that the 100 grainer is moving at least 300 fps faster, I would have thought the small difference in weight would have been compensated for in energy with the 300 fps advantage. Not so as it appears?
Well I continued with my research by loading up a 120 gr. solid copper projectile and a 100 grain solid as well. The 100 grainer @ 3623 fps fractured the opposit side and looked promising to me as a long distance deer hunting load. So I loaded up the 120 gr. solid @ almost 3300 fps and expected a simular performance as the 120 gr. jacketed Hornady round, but I was astonished to discover that it will not go through. It did produce a very visable fracture on the opposit side, but several trys didn't improve nor change it's effect on the steel.
So after these rather poorly controlled testing senario's, I decided to put a thin skinned 5 gal. plastic container filled with water behind it to catch what ever comes through, thinking this mght help answer some questions. But it actually presented me with more questions than answer's. I put the 120 gr. jacketed bullet through, and when the round punched through the water container it nearly exited as well, leaving a split on the opposite side. When I looked to see what was left of my bullet, I discovered what was laying on the bottom of the water container appeared to be a steel half moon .510" diameter plug that weighted in at 28 grains more than the projectile, 148 grains. When I got home I heated the plug with a propane tourch so I could melt away any lead. To my surprise the plug had no lead to be found. So now I'm thinking that it is shear energy that punched the hole. It looks like it was perfectly cut with a plasma cutter, and not even a small frag of lead or copper could be found in the water jug.
In future steel plate testing I tried some heavier bullets, 130 gr. jacketed PSP, 139 gr. PSP, and a 168 gr. PSP. all but the 168 grainer went through, but the 168 did leave a nasty crater and was very close to breaching the opposite side. So now I'm kind of thinking I can use this information to at least some degree regarding penetration. In this repsect, I'm kind of thinking that a 130 gr. to 140 gr. is going to produce the best penetration on dense tissue game, bear elk and such. It seems at some point a heavier projectile looses it's ability to penetrate because it's velocity drops below an effective range, much in the same respect as to the lighter faster bullet looses it's effective mass, to utilize it's extreme velocity, but in a reverse manner. In other words, it appears the heavier mass at a lower velocity of 3050 fps average, isn't enough to maintain enough energy to breach the steel. But on the other side of this is the lighter bullet, which I pushed at up to nearly 3700 fps in my final attempt, still doesn't have enough mass to breach the plate. I also tried the HP 100 gr. and 110 grain bullets with nearly identical results as the PSP 100 gr. projectile, theydon't get through.
So now I think I've found that the optimum penetrating projectile seems to be between 130 gains and 145 grains. For mule deer, I think either of those are going to produce a good clean entry and exit hole. But if I were hunting something a little bit more dense such as elk or bear, I would probably not go any lighter than a 145 grain projectile, but probably not any heavier either.
I'm now thinking the "bigger is better" mentallity may not be the optimum choice, especially at distances out to 300 yds.. So I'm still not sure about extreme distances of over 500 yds. and up to 800 yds, which weight .284 projectile is going to provide a good clean kill on mule deer sized game. I once thought the solid copper projectile was a magical pill in this respect, but even that is starting to look bleak in relation to the steel penetration experiements, with lead clearly out performing them.
I've sucessfully hunted everything from antelope to elk and bear with both the .270 win, and the 7mm RM over the last several decades. Many of my kills have been at distances out to and beyond 500 yds. with all kills acomplsihed with the mid weight projectile. I have always hand loaded bullets that have never exceeded 145 grains for the 7 mag., and 130 grains being the heaviest for the .270 Win. for these animals of the southwest. But recent events have forced me to question my choices, primarily speaking I'm trying to rule out pure luck, as the common denominator here.
Has anyone else possibly done more extensive testing or can contribute their perspective based on an event or possibly an extensive study, and even some relative results from a hunting experience that may shead some more light on the optimum long range pill, primarily the 7mm RM or potentially simular velocity .284" projectile. Your thoughts and perspectives are open mindly welcomed on this topic. I've long enjoyed proving or eliminating various therory's and opinions, almost as much as the sport of big game hunting it's self. But like most who enjoy reloading, I'm always searcing for the magical pill that will do it all at just about any distance, and I think I might have discovered some specifics that help explain my findings enough for my specific application. Though the steel plate has provided some standard of performance, the ability to dispatch big game at long range is the motive behind wasting all those bullets.
I started with a 120 gr. standard Hornady PSP bullet @ 150 yds. down range @ a chronographed M.V. velocity of just under 3300 fps, it consistently and completely blows through a 1/2" piece of average grade plate steel. However, a bullet only 20 grains lighter at a velocity of nearly 3600 fps doesn't get through and barely fractured the opposit side. Both bullets are nearly identical in structure, I have sliced them in half from heel to tip and everything looks to be equal in jacket thickness less the 20 grains of weight in the 100 grain projectile. Considering that the 100 grainer is moving at least 300 fps faster, I would have thought the small difference in weight would have been compensated for in energy with the 300 fps advantage. Not so as it appears?
Well I continued with my research by loading up a 120 gr. solid copper projectile and a 100 grain solid as well. The 100 grainer @ 3623 fps fractured the opposit side and looked promising to me as a long distance deer hunting load. So I loaded up the 120 gr. solid @ almost 3300 fps and expected a simular performance as the 120 gr. jacketed Hornady round, but I was astonished to discover that it will not go through. It did produce a very visable fracture on the opposit side, but several trys didn't improve nor change it's effect on the steel.
So after these rather poorly controlled testing senario's, I decided to put a thin skinned 5 gal. plastic container filled with water behind it to catch what ever comes through, thinking this mght help answer some questions. But it actually presented me with more questions than answer's. I put the 120 gr. jacketed bullet through, and when the round punched through the water container it nearly exited as well, leaving a split on the opposite side. When I looked to see what was left of my bullet, I discovered what was laying on the bottom of the water container appeared to be a steel half moon .510" diameter plug that weighted in at 28 grains more than the projectile, 148 grains. When I got home I heated the plug with a propane tourch so I could melt away any lead. To my surprise the plug had no lead to be found. So now I'm thinking that it is shear energy that punched the hole. It looks like it was perfectly cut with a plasma cutter, and not even a small frag of lead or copper could be found in the water jug.
In future steel plate testing I tried some heavier bullets, 130 gr. jacketed PSP, 139 gr. PSP, and a 168 gr. PSP. all but the 168 grainer went through, but the 168 did leave a nasty crater and was very close to breaching the opposite side. So now I'm kind of thinking I can use this information to at least some degree regarding penetration. In this repsect, I'm kind of thinking that a 130 gr. to 140 gr. is going to produce the best penetration on dense tissue game, bear elk and such. It seems at some point a heavier projectile looses it's ability to penetrate because it's velocity drops below an effective range, much in the same respect as to the lighter faster bullet looses it's effective mass, to utilize it's extreme velocity, but in a reverse manner. In other words, it appears the heavier mass at a lower velocity of 3050 fps average, isn't enough to maintain enough energy to breach the steel. But on the other side of this is the lighter bullet, which I pushed at up to nearly 3700 fps in my final attempt, still doesn't have enough mass to breach the plate. I also tried the HP 100 gr. and 110 grain bullets with nearly identical results as the PSP 100 gr. projectile, theydon't get through.
So now I think I've found that the optimum penetrating projectile seems to be between 130 gains and 145 grains. For mule deer, I think either of those are going to produce a good clean entry and exit hole. But if I were hunting something a little bit more dense such as elk or bear, I would probably not go any lighter than a 145 grain projectile, but probably not any heavier either.
I'm now thinking the "bigger is better" mentallity may not be the optimum choice, especially at distances out to 300 yds.. So I'm still not sure about extreme distances of over 500 yds. and up to 800 yds, which weight .284 projectile is going to provide a good clean kill on mule deer sized game. I once thought the solid copper projectile was a magical pill in this respect, but even that is starting to look bleak in relation to the steel penetration experiements, with lead clearly out performing them.
I've sucessfully hunted everything from antelope to elk and bear with both the .270 win, and the 7mm RM over the last several decades. Many of my kills have been at distances out to and beyond 500 yds. with all kills acomplsihed with the mid weight projectile. I have always hand loaded bullets that have never exceeded 145 grains for the 7 mag., and 130 grains being the heaviest for the .270 Win. for these animals of the southwest. But recent events have forced me to question my choices, primarily speaking I'm trying to rule out pure luck, as the common denominator here.
Has anyone else possibly done more extensive testing or can contribute their perspective based on an event or possibly an extensive study, and even some relative results from a hunting experience that may shead some more light on the optimum long range pill, primarily the 7mm RM or potentially simular velocity .284" projectile. Your thoughts and perspectives are open mindly welcomed on this topic. I've long enjoyed proving or eliminating various therory's and opinions, almost as much as the sport of big game hunting it's self. But like most who enjoy reloading, I'm always searcing for the magical pill that will do it all at just about any distance, and I think I might have discovered some specifics that help explain my findings enough for my specific application. Though the steel plate has provided some standard of performance, the ability to dispatch big game at long range is the motive behind wasting all those bullets.
