Always an interesting topic and I think the main points have been covered already. Knowledge, skill, practice, projectile choice and shot placement all come before cartridge and calibre. I’m not up for another argument about .243 vs the rest so I’m gonna try and take the discussion in another direction.
The part of the discussion that I think is confusing matters slightly when subjectively comparing cartridge performance, is shot placement. I raised this in another thread a couple of days ago and didn’t get a bite so I shall have another go.
http://www.thedeerinitiative.co.uk/uploads/guides/161.pdf
Read the second paragraph under the heading “Chest”.
“A common reaction to a lethal chest shot is that the deer will run a short distance, then collapse, dead. A shot slightly more forwards, which involves both shoulders, is equally humane and will usually cause the animal to drop on the spot.”
So far I have not told you anything you don’t aleady know, right? But I want to focus on the second sentence. Because this is the key to why deer run, or don’t, irrespective of what cartridge / calibre you are using.
I chose a UK publication because I don’t see it discussed much there. But seek, ye shall find. I was taught centrefire deer shooting from 12 onwards by my Grandpa, in the UK. He was a staunch fellow, but not one for large calibres. He moved on the .243 in the late 50s I believe and stayed with it for the rest of his life. He shot many hundreds of game animals with his CZ .243 Win. Now he taught me, and my cousins, to select a point of aim 1”
in front of the line of the foreleg at the height of the centreline of the shoulder blade. Specifically, to avoid a heart shot.
This point of aim is commonly taught in NZ. The link to the book below discusses it in detail, as does Nathan Foster in his books.
Red Deer in New Zealand : Roger Lentle : 9781869530372
This book is in every public library in the country. It is the Bible of all things red deer. The following image discusses where to shoot deer:
View attachment 89216
Now obviously I am well aware that most experienced deer shooters talk about heart / lung shots, and in the Deer Initiative pamphlet and many, many other books, we are told to shoot in line with the shoulder and just
behind the vertical line of the foreleg.
But this is why can deer run away on you. Hit a deer here with a .243 or a .30-06, it will likely run, often not far but sometimes very far, because even if the heart has been stopped it can lock oxygenated blood into the brain and the animal will keep thinking “I must run” until suddenly the blood pressure drops below the point it can maintain locomotion. How far depends on a multitude of factors, the amount of andrenaline released at the time of impact being one of them. Sometimes, animals are lost due to running into thick cover, or as has been mentioned earlier in this thread, over a boundary fence (not cool). And this is of course why blokes are stuck on needing an exit wound, to track a running animal.
By selecting the forward point of aim, you are targeting the front of the lungs, where the complex of arteries and autonomic plexus nerve ganglia that connect the brain to the heart and lungs are situated. A shot here with a .222 will kill the animal, often with the dead right there “bang flop” we aspire to. You’ve all seen the videos and read the stories of the Kiwis and their Sako Vixen .222s. That is what these guys were doing with these accuate wee rifles, using traditional soft point projectiles. The front on chest shot was highly favoured, as was the side on, front line of foreleg. Another favourite is the feeding position below and facing away from the shooter on an opposing steep slope, with the head facing uphill, thus presenting a clear view of the spine between the front shoulders.
The obvious advantages of using a high-powered Magnum cartridge, or heavy for calibre .270, .308 or .3006 etc, is that the correct type of projectile will deliver a lot more energy to the POI and potentially induce hydrostatic and/or hydraulic shock. But, again in my experience, I’ve stood behind a fair few guys as they struggle for accuracy with hard kicking lightweight hunting rifles. So they default back to the shot placement that they believe will give them the highest probability of a kill, and aim for the area behind the shoulder... and curse and swear as they get a runner disappearing into the forest despite the fact that they’ve hit it with a tank shell.
Next it’s my turn with my poxy .243 Win, and at 300m the animal jumps with an arched back, staggers a few paces, drops at the rear, then falls over dead, the neck curving back tight against the shoulders. A sure sign you’ve disrupted the nerve plexus - when you dress it out, conveniently in the same place you shot it, you’ll find the front of the lungs destroyed and the main arterial connections to the heart have bled out very fast, the chest cavity will be swimming in blood.
So back to the issue of whether 6mm, most commonly in the form of .243 Win, is enough gun for deer. My view, clearly, is that yes it is. My view, in the manner I was taught, is that shot placement has confused a lot of guys into thinking that they don’t have a big enough cartridge. I am frequently amazed by some of the things I read, here and elsewhere. Some of the debates we have about calibre and cartridge are well meant, and quite funny, but the underlying message to me at least is that quite a lot of guys don’t truly understand why their deer run so far. It’s not surprising really because just about every manual you’ll read will tell you: shoot them on the animal’s midline behind the shoulder. Watch it for yourself on YouTube there are hundreds of videos of precisely this, you can see the bullet strike, and .....the deer take off like a Paveway missle. The only scenario I regard heavy bullets as a prequisite is true long range hunting, for their ballistic performance.
So to conclude... yes the .243 Win is “adequate” on medium game. Of course it is. If, however, you prefer to use a heavier bullet in a cartridge that delivers more energy, then go for it. Use whatever you enjoy shooting, and what you can demonstrate you are capable of delivering prerequsite accuracy with. If you want to buy a .30cal because you believe it is going to stop your deer from running, think again.
(A closing comment would be that at the ranges most of the UK high seat shooting is conducted at, and probably most of the offhand or stick or bag based shooting in fields, a well practised shooter should be able to drop any deer species on the spot with a .224 were they legal in England, but certainly with a .243. I don’t want to stir you up but with all the naval gazing about sub MOA accuracy at 100 or 200yds, only to then read in the next thread that someone does not believe a 95gr 6mm hunting pill is enough for roe at 150 yds, well it just doesn’t make sense. Most of the deer shooting in the UK - some Scottish hill shooting aside - is at short range, sub 300yds. That is precisely what the .243Win was designed for. Shooting out of a high seat at 100yds and fretting that you don’t have enough gun suggests something else might require fine tuning before you buy a bazooka.)