Terminal Ballistics at Distance - KE, OGW, TKO, MO and KPS formulas

[Stinky Coyote]

The example of the guy with the 416 shooting a mountain goat, only illustrates that the cartridge/bullet for that application was most likely a poor choice. The majority of 416 bullets are heavily constructed controlled expansion, large in caliber and heavy in weight. Mountain goats have relatively thin body widths. Lighter weight cartridges/bullets with faster bullet expansion characteristics are going to be preferable. Case in point is the guy shooting the .270 WIn.

Discussing SD's with a frame of reference to shooting SOLID bullets out of a 6.5 CM versus a 375 H&H, seems irrelevant to a discussion where we're talking about hunting North American big game, in the Long Range forum.

The key focal points, from my perspective, are to pick a cartridge and bullet combination that are as versatile/well-rounded as possible, considering the target animal and most likely shot yardages. In order to do that; two of the very important factors that need to be considered are energy at the target and the design characteristics of the bullet.

yes but showing the extremes shows us the perspectives the fastest and keeps things the least muddy in these discussions...the subjective of the 416 vs 270 goat is that the 416 should have turned the goat into a canoe looking at energy values but just poked a couple unimpressive holes...but it's the .270 that flattens them as if hit by lightning....and energy has nothing to do with it, nothing makes it clearer than examples like this

well not in how we measure energy anyway, we can't yet quantify objectively how many ft/lbs per inch over what distance the 416 would do vs the .270 to show why the .270 is a far better choice for a goat and the 416 for a rhino, we will see this one day though, I bet guys are working on it right now

here's my view of that example, the .270 was able to dump 100 ft/lbs per inch over 20" so majority of work landed inside the animal and flattened it, the 416 was able to dump a fractional amount per inch but could do that through 4 goats lined up lol...but being there was only one goat all the work went into the mountain side and the goat took a minute to die while the mountain still probably feels the sting to this day lol

 

[MaraviaDave]

Also, interesting your 375 hh and 270gr barnes combo, a bit of 21st century added to an early 20th century case. Running about 2730 fps, .449 bc, .274 sd (which in a barnes it will retain very well) and at 400 yards you'll impact about 2000 fps and that barnes will barely open up. Internal damage should be fairly unimpressive.

The 21st century answer to this for those giant moose that came to mind was the new 6.8 Western running 175 gr bullets. 2835 fps, .617 bc, .326 sd (with likely more rapid expansion construction than barnes) and at 400 yards you'll impact about 2330 fps and you'll do it burning about 20 grains less powder.

I think you'd see more than enough penetration with that 6.8 175gr combo for those big moose with that huge initial sd but a ton more internal damage with this combo as it's going to do an incredible amount of work over say 36" vs the slower 270gr barnes that will barely be opening up at that impact velocity. You should see shorter recoveries and far more internal damage with the lighter recoiling lower ko value example here. Food for thought...but we seem to be comparing some 20th century subjective views here against 21st century understandings. Energy/momentum/ko factors are pretty useless figures for what we do in North America.

That 6.8 Western is going to be a bit of a sleeper that will earn it's reputation slowly, that .326 sd is a monster that allows a lot of the front half of that long bullet to expand and do work internally while having lots of tail end of bullet left (retained sd) to keep driving deep on bigger critters. I don't think the 6.8 Western will even blink on deer/elk sized game so it may seem unimpressive until you get into those big bears and moose up north.

You've got a combo that works and you prolly built it before the 6.8 Western even came along but if a guy was building for the same needs you ask now...there are more options and several will use a lot less powder for more efficiency and likely perform better than barnes as well. Not only that but this example the 375 barnes combo is about wrapped up at 400 yards...the 6.8 Western example is just getting warmed up at 400 yards, with that .617 bc it's drifting and shedding velocity WAY less than the big fat boat...likely nearly double your effective range...yup I just checked, your 2000 fps comes in at 700 yards with the 6.8 combo.

I know which one I'd choose for those giant moose, the one with the cheesy name but all the right numbers, it would be like the Alaskan Manbun Cartridge lol.

There's a difference between field experience and sitting at home punching numbers into a ballistic calculator.

That's not to say that both aren't important. But rather, the most valuable knowledge comes from crunching the numbers, making an informed decision, then validating the assumptions in the field to determine if you were correct. Admittedly from small sample sizes. But, you have to have a frame of reference to start from.

I've hunted with fast 30 cal magnums and eventually moved to the cartridge/bullet combo I'm shooting now. Also hunted with guys using calibers ranging from 7mm to various 30 cal's. Without a doubt the effects of a 375 caliber 270 grain LRX have been spectacular. A couple of my buddies have built 375's after seeing bulls killed by me versus the bulls they've killed.

 

[MaraviaDave]

yes but showing the extremes shows us the perspectives the fastest and keeps things the least muddy in these discussions...the subjective of the 416 vs 270 goat is that the 416 should have turned the goat into a canoe looking at energy values but just poked a couple unimpressive holes...but it's the .270 that flattens them as if hit by lightning....and energy has nothing to do with it, nothing makes it clearer than examples like this

I believe you're missing the most critical point.........bullet construction in relationship to the target animal.

I appreciate the discussion. At this point, we're just reiterating the same points. I've definitely considered what you've said, which has been interesting.

 

[Stinky Coyote]

There's a difference between field experience and sitting at home punching numbers into a ballistic calculator.

That's not to say that both aren't important. But rather, the most valuable knowledge comes from crunching the numbers, making an informed decision, then validating the assumptions in the field to determine if you were correct. Admittedly from small sample sizes. But, you have to have a frame of reference to start from.

I've hunted with fast 30 cal magnums and eventually moved to the cartridge/bullet combo I'm shooting now. Also hunted with guys using calibers ranging from 7mm to various 30 cal's. Without a doubt the effects of a 375 caliber 270 grain LRX have been spectacular. A couple of my buddies have built 375's after seeing bulls killed by me versus the bulls they've killed.

we certainly agree that this is a very subjective topic still, I'm sure I'd be shooting something very different if I lived and hunted where you do, you came up with what you like through the subjective trial and learning over time application as have I, when you study the numbers of the experiences you know you can then future predict much better what combos will work for what

I've shot delayed controlled expansion with bigger horsepower in my trials over time and at this point I've come down the other side of the hp ladder and prefer to place it easier and run higher than necessary sd with rapid expansion bullets at moderate velocities as giving better than numbers suggest performance. That formula for me up north would likely land closer to the western than the 375 and neither would be a bad choice obviously as dead is dead and the moose aren't going to take either option and walk away. Some just don't need as much insurance as others I guess. We are on the same page in most respects...it's just that pesky energy thing we are not seeing eye to eye on.

and 100% understand bullet construction for game intended relationship to sd for said bullet construction for said game intended and the impact velocity ranges to work that bullet construction and sd properly for said game intended....I got that part down pat don't worry

it's easy to see right on this forum the extreme opposite end of the 375 example...head to the .223 thread , now lots of us just aren't quite ready for that, I am more than most as I feel a little over compensated with my little 6.5 Grendel current choice of fun and we're at 12 for 12 on 5 species of big game in this house up to 420 yards now so I guess I'm nearly at the opposite end of spectrum of your choice but I didn't get there just out of high school, nearing 50 years old now so shot a lot of stuff with bigger rigs, the more you do this the more questions you can end up with as things that shouldn't work by 20th century subjective views work spectacularly and vice versa...we have long ways to go to get terminal ballistics far more objectively understood

 

[MaraviaDave]

we certainly agree that this is a very subjective topic still, I'm sure I'd be shooting something very different if I lived and hunted where you do, you came up with what you like through the subjective trial and learning over time application as have I, when you study the numbers of the experiences you know you can then future predict much better what combos will work for what

I've shot delayed controlled expansion with bigger horsepower in my trials over time and at this point I've come down the other side of the hp ladder and prefer to place it easier and run higher than necessary sd with rapid expansion bullets at moderate velocities as giving better than numbers suggest performance. That formula for me up north would likely land closer to the western than the 375 and neither would be a bad choice obviously as dead is dead and the moose aren't going to take either option and walk away. Some just don't need as much insurance as others I guess. We are on the same page in most respects...it's just that pesky energy thing we are not seeing eye to eye on.

and 100% understand bullet construction for game intended relationship to sd for said bullet construction for said game intended and the impact velocity ranges to work that bullet construction and sd properly for said game intended....I got that part down pat don't worry

it's easy to see right on this forum the extreme opposite end of the 375 example...head to the .223 thread , now lots of us just aren't quite ready for that, I am more than most as I feel a little over compensated with my little 6.5 Grendel current choice of fun and we're at 12 for 12 on 5 species of big game in this house up to 420 yards now so I guess I'm nearly at the opposite end of spectrum of your choice but I didn't get there just out of high school, nearing 50 years old now so shot a lot of stuff with bigger rigs, the more you do this the more questions you can end up with as things that shouldn't work by 20th century subjective views work spectacularly and vice versa...we have long ways to go to get terminal ballistics far more objectively understood

I appreciate your posts and your perspective. Thank you!

 

[Rich M]

you could likely do very similar work with a .17 hmr and not the v-max bullet, the xtp or even tnt would likely do

a little visit to the .223 thread would confirm that

good combo and I like your method and choice, I still think one day I'll get the little ruger 77/357 and put the Leupold ultralight fixed 2.5x on it but

REALLY like the M77/357 - great lil gun. Have a 2-7x Viper and a 4x Banner scopes i use on it. The viper is the original USA made stuff and the Banner has a heavy circle plex.