A little help….caliber selection

nksmfamjp

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Jan 5, 2004
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So, I'm trying to figure out cartridge, bullet, barrel lengths and twist rates in some logical fashion. Kind of makes you dizzy!

First I tend to focus on the animal. I figure to have the best chance there, I need best possible accuracy, expansion, and an exit.

Thinking about accuracy, I'm mostly focused on minimizing recoil which tends to push the cartridge to a minimum bullet weight and case capacity. That works. I'll admit, I shoot a 6.5 Creedmoor better than a 300 WM.

Then expansion. There are definitely cases where expansion is not required. Heart shots in just the right spot, brain, spinal shots. That said, especially at long range, I want an expanded bullet to the vitals. So, I want a bullet running over 1800 fps at max range. My legit max range now is 400. I am working to be good at 600. This has come down quite a bit in the last couple years because I'm more conservative about what shots I will take. As you can imagine, bc, personal effective range, barrel length, case capacity all play a role.

Then, I believe based on hunting experience that I need an exit. I struggle to know by the numbers if a bullet will exit. My thoughts are…., a bullet enters with kinetic energy. This energy does work on the bullet and on the animal. If it lacks enough energy, that will allow the bullet to stop. So, what is a minimum or a target? I go back to a near 0 work example. A 44 mag cast solid, imo will kill a mule deer buck at 120 yards with minimal left over. It will exit. That is about 600 ftlbs. So, I set that as my energy minimum to exit deer. I use 1000 for elk, but I really don't know about that.

So, does this make logical sense? Am I missing something big? Yes, I'm definitely overthinking it!
 
Give a 280AI a look. I recently traded for one and it is probably the nicest rifle, shooting wise I have ever owned and I have two safe's full. I shoot 143 grain Hammer Hunters in it and it shoots better than 1/2 MOA at 3250FPS and has no recoil. The rifle does have a brake on it, but what rifle doesn't anymore. You can load them all the way to 190 grain bullets if you want. It is just seems to be a very accurate and pleasant shooting round. JMO but food for thought.
 
So, I'm trying to figure out cartridge, bullet, barrel lengths and twist rates in some logical fashion. Kind of makes you dizzy!

First I tend to focus on the animal. I figure to have the best chance there, I need best possible accuracy, expansion, and an exit.

Thinking about accuracy, I'm mostly focused on minimizing recoil which tends to push the cartridge to a minimum bullet weight and case capacity. That works. I'll admit, I shoot a 6.5 Creedmoor better than a 300 WM.

Then expansion. There are definitely cases where expansion is not required. Heart shots in just the right spot, brain, spinal shots. That said, especially at long range, I want an expanded bullet to the vitals. So, I want a bullet running over 1800 fps at max range. My legit max range now is 400. I am working to be good at 600. This has come down quite a bit in the last couple years because I'm more conservative about what shots I will take. As you can imagine, bc, personal effective range, barrel length, case capacity all play a role.

Then, I believe based on hunting experience that I need an exit. I struggle to know by the numbers if a bullet will exit. My thoughts are…., a bullet enters with kinetic energy. This energy does work on the bullet and on the animal. If it lacks enough energy, that will allow the bullet to stop. So, what is a minimum or a target? I go back to a near 0 work example. A 44 mag cast solid, imo will kill a mule deer buck at 120 yards with minimal left over. It will exit. That is about 600 ftlbs. So, I set that as my energy minimum to exit deer. I use 1000 for elk, but I really don't know about that.

So, does this make logical sense? Am I missing something big? Yes, I'm definitely overthinking it!

I won't suggest that you're over complicating it…..but, I am a "simpleton" with "simpleton" methods/ideas!

I choose a cartridge based upon the largest, possibly most dangerous, game that I will ever hunt at the maximum ranges that I'm likely to ever shoot at game. I then factor in the greatest recoil that I'm comfortable with……not in a rifle/cartridge that will see 100's of rounds fired from a bench, but a hunting rifle. Also factored in, is going with the lightest rifle to cover those bases……as I often (or used to) cover a lot of miles on a hunt often in hilly terrain!

Using that concept…..I built my "only" hunting rifle in 1990. It has never failed to live up to my desires/expectations! memtb
 
My Kimber Montana 280AI with Hornady Precision Hunter 162ELDX has served me (and others who borrowed it) well across multiple mule deer and antelope from 75 to 400 yards.

If started from scratch - I would get a Tikka in 6.5 Creedmoor with a 22ish inch threaded barrel and a suppressor (or a 6mm Creedmoor/243/260) and invest in a lot of practice and some formal training.
 
I won't suggest that you're over complicating it…..but, I am a "simpleton" with "simpleton" methods/ideas!

I choose a cartridge based upon the largest, possibly most dangerous, game that I will ever hunt at the maximum ranges that I'm likely to ever shoot at game. I then factor in the greatest recoil that I'm comfortable with……not in a rifle/cartridge that will see 100's of rounds fired from a bench, but a hunting rifle. Also factored in, is going with the lightest rifle to cover those bases……as I often (or used to) cover a lot of miles on a hunt often in hilly terrain!

Using that concept…..I built my "only" hunting rifle in 1990. It has never failed to live up to my desires/expectations! memtb
Interesting….what is it?
 
So, I'm trying to figure out cartridge, bullet, barrel lengths and twist rates in some logical fashion. Kind of makes you dizzy!
Read up on Modern Cartridge Design.
A 280AI fits the bill here for anything in North America.

 
Then, I believe based on hunting experience that I need an exit. I struggle to know by the numbers if a bullet will exit. My thoughts are…., a bullet enters with kinetic energy. This energy does work on the bullet and on the animal. If it lacks enough energy, that will allow the bullet to stop. So, what is a minimum or a target? I go back to a near 0 work example. A 44 mag cast solid, imo will kill a mule deer buck at 120 yards with minimal left over. It will exit. That is about 600 ftlbs. So, I set that as my energy minimum to exit deer. I use 1000 for elk, but I really don't know about that.
The resistance of an object is a function of the square of its velocity, so the faster a bullet travels, the more resistance it will encounter when penetrating an animal - that is why the same bullet at a faster speed "blows up" - it is encountering a lot more resistance than a slower bullet. Of course, bullet construction rules - something that expands quickly is going to encounter even more resistance.

Bullets, unlike (most) arrows, expand as a function of velocity, so you can't compare a cast .44 bullet's penetration vs a .243 going three times as fast.
 
Interesting….what is it?

First……a qualifier!

I've always leaned toward larger calibers, had a desire to hunt Alaska and Africa…….so naturally, I bought a .375 H&H.

Upon moving to Wyoming, lugging that heavy Model 70 around and also realizing that long shots could easily be on the menu, meeting some folks more knowledgeable about firearms than me, and one of them being a gunsmith……I made plans for my perfect all around rifle.
As Alaska and Africa were still on the agenda……I decided on a .375 AI.

At 9 pounds 1 oz. scoped, loaded and slung, while not a "featherweight" it's portable enough. Its velocity allows for shots beyond that of my self-imposed range limits, components are (or at least were) readily available, and works quite well from small big game (deer/antelope) up to anything I'm subject to hunt! It's even been used on more than a few coyote hunts.

While this borders on open blasphemy on this forum……I'm a one rifle/cartridge hunter. memtb
 
Based on those assumptions, plus wanting factory hunting loads of pretty good performance, I'm kind of looking at 6mm Creedmoor, 243 Win or AI….fast twist, 25-06 ai, 6.5 Creedmoor, 6.5x55, 6.5 RPM, 6.5x284, 270 Win or AI…..fast twist, 280 AI
 
Based on those assumptions, plus wanting factory hunting loads of pretty good performance, I'm kind of looking at 6mm Creedmoor, 243 Win or AI….fast twist, 25-06 ai, 6.5 Creedmoor, 6.5x55, 6.5 RPM, 6.5x284, 270 Win or AI…..fast twist, 280 AI

Given those to choose from……the 280 AI is a sweet cartridge! memtb
 
Based on those assumptions, plus wanting factory hunting loads of pretty good performance, I'm kind of looking at 6mm Creedmoor, 243 Win or AI….fast twist, 25-06 ai, 6.5 Creedmoor, 6.5x55, 6.5 RPM, 6.5x284, 270 Win or AI…..fast twist, 280 AI
If your not handloading go with the 280ai.
If you handload either the 280ai or 25-06ai. I have both and favor the 25-06ai but mine is a 7 twist.
 
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