Heavy and Slow Terminal Ballistics

liamnjs

Well-Known Member
This is not a "vs" thread. I have read Rathcombe, I have read Chuck Hawks and I have read Ballistics Studies (the latter being my favourite), I have a reasonable handle on the theories relating to wounding and why velocity may be important.

My question is what are the competing theories indicating "heavy and slow" cartridge/bullet selection? Is it simply increased penetration and potentially greater (if less rapid) overall expansion resulting resulting in greater wound surface area and more rapid bleed out? Or is there more to it? If that is the case then would this not be contra-indicated by the potential for over-penetration on light bodied game?
 
Over penetration? Seeing as how most bullets exit our deer species is this then not over penetration?

Let's face it the idea of a bullet staying inside and dumping all it's energy is one that's long been speculated upon. For me I sort of stick to the middle ground. Any bullet that exits the barrel at around 2700-3,000 fos is going to do the job any any normal ranges, for me anyway, will do the job. Occasionally I may recover a bullet, it's happened twice, but normally they pass on through and the deer drop. Sometimes they cover a few yards but often they drop pretty much where they are shot. Even without a dog I have not lost one although it would have been a close thing with a Muntjac doe shot using a borrowed .243 and federal ammunition. As it's working for me i will keep doing things the same way.
 
heavy bullets for the same cartridge are slower by nature, so on thin skinned game will usually keep damage down as they are mostly expanding on the way out.
*(not saying either is the best thing)
I believe they are less deflected by light brush or bone also somight be better for less then perfect shots.
For roe doe stalking in my 6.5x55 i use 139's as shots might be longer then the summer bucks who are often stood among bracken and brambel when the 156RN's seem to always find their way and as the range is shorter meat damage is nil.
My 7mm rem i use 162+ as they are very good on everything from roe to moose and pig.
Then theres the 9.3 with very heavy 285 RN and if shooting driven game at short range no one can argue with its ability to find a path through birch scrub and stuff the 6.5 would fail on.
The terminal ballistics are very lethal.
I have owned 2506, 7mm rem mag .243 and many other fast cartridges but like slower heavy bullets these days even on smaller game.
This isn't on anything i've read but based on my findings from field use of me and clients shooting roe- pigs (abroad).
 
The big two competing theories for chest shots seem to me to be the magical high-velociy-induced (i.e. 'hydrostatic shock'-realted) instant death vs. an adequate hole caused by whatever means leading to more-or-less rapid bleeding out.

As BH pointed out, most deer bullets would be expected to exit, so overpenetration is perhaps not an issue.

I guess heavy and slow needs a bullet that will expand adequately at lower speeds, but apart from that the advantage seems to be that less of a smack on the way in and out causes less bruising or damage to what one might eat, while making an adequate mess of the working parts within to kill the beast quickly.
 
So it seems reducing meat damage is one plus for using slow and heavy, and the reduced chance of deflection on the way to the target is another.

When I mentioned over penetration, I suppose I am referring to a bullet that exits without having "dumped energy" into the target, but I take the point that most bullets exit.

What interests me most about this is the mechanics of rapid killing, and how "slow and heavy" can contribute. As I understand it the two schools of thought on fast killing surround hydrostatic shock affecting the CNS and wide temporary and permanent cavitation resulting in massive bleeding and sudden drops in blood pressure. Assuming a heavy, slow moving bullet expands fully would it be correct to assume that exponents of "heavy and slow" would argue it is going to reliably create large wound surface area, thus fast bleeding and drop in blood pressure, resulting in a fast kill?
 
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The big two competing theories for chest shots seem to me to be the magical high-velociy-induced (i.e. 'hydrostatic shock'-realted) instant death vs. an adequate hole caused by whatever means leading to more-or-less rapid bleeding out.

As BH pointed out, most deer bullets would be expected to exit, so overpenetration is perhaps not an issue.

I guess heavy and slow needs a bullet that will expand adequately at lower speeds, but apart from that the advantage seems to be that less of a smack on the way in and out causes less bruising or damage to what one might eat, while making an adequate mess of the working parts within to kill the beast quickly.

And that's the crux of the issue right there. I have killed deer with 210 grain 30 caliber cast bullets at 1800 fps that have left 1+" exit wounds at 100 yards on a properly placed shot. The Hornady 220 grain soft point, round nose expands almost as well at the same velocities showing it might have been engineered with the old Krag Jorgensen 30-40 in mind which has a top speed of 1900 with that bullet.

This is an extreme example but shows that heavy and slow works but you need the right bullet.~Muir
 
sports car hits deer and kills it so will a truck at half the speed.
now the deer is stood behind a telegraph pole.
sports car warps its self around the pole and deer runs off, truck takes out both.
maybe not a great comparison but it makes a point, also the truck driver might survive doubt the boy racer will, heavy construction at lower speeds has its place.
 
My view is that 'energy dump', 'hydrostatic shock' and the like simply cloud the issue.

The killer is sufficient damage to the working parts, and that means a hole through the right place.

As far as I can tell, if you make the hole with a fast bullet of the right construction, you risk more meat-bruising than with a slow bullet of the right construction.

Hence the basis for choosing a fast bullet can only be the desire for a flatter trajectory and less-marked effects on POI from shoooting up or down hill: which is IMO useful where longer shots might be necessary, as in hill-stalking.

Heavy and slower for shorter ranges seems to be a good choice.
 
When I mentioned over penetration, I suppose I am referring to a bullet that exits without having "dumped energy" into the target, but I take the point that most bullets exit.

Energy is the ability to do work and, therefore, it is impossible to "dump energy" as you simply can't leave a pile of it sitting around. The bullet has energy and it uses this energy to do work - some of it will go as sound and heat while some will be used to destroy or damage or move tissue and I suspect that the larger part of the energy "dumped" in an animal goes into the deformation of the actual bullet and this is supported by the concern that a very high velocity bullet might "blow up" on a shoulder for example. Such a high velocity bullet that "blows up" on a shoulder is using almost all its energy deforming and destroying the projectile and a small amount causing surface tissue damage, bullets which penetrate to the vital organs but fail to exit are doing a similar thing but the outcome is more satisfactory to the stalker.

Any bullet that exits will still have the ability to do some work even if that is just struggling against air resistance for a few yards. This energy is not "wasted" in the sense that it could have been left behind in a neat little pile inside the animal because by this stage the bullet will have done its job and (hopefully) put a goodly hole in some vital organs which is the only reliable way to kill an animal within the context of this discussion.

Where a high velocity bullet might have a slight advantage over a heavy and slow one might be that under some very specific circumstances and given good luck one might deform at just the right place inside an animal such that the various fragments might fly about a bit and cause some damage in addition to that caused by the main mass of the bullet. However, should this fragmentation happen an inch too soon, or an inch too late, there may be no benefit and the effect may be to reduce the killing power of the bullet. Slow and heavy, as long as it is fast enough to ensure reasonable expansion and an exit, will never suffer from this virtually random game of chance.
 
Bullet construction and strength clouds the issue to make it harder. For example I stopped using a load in my 6.5x55 using the Hornady 160 Grn RNSP on Roe Deer as it was too brutal. probably be fine on Fallow bucks but it ruined a whole shoulder, it jellified it, and the 6.5x55 is not a speed king with that bullet. Range was 90 paces to that was not the issue. It might have been a one off but I was not going to risk it again on the Roe Does.

My old stalling mentor claimed that bullets exiting the muzzle about 2800fps did best, caused less carcase damage yet killed cleanly, God only knows how many deer he had taken in his career and life and been witness to many ............................ many more and what's more in my own limited experience this seems to work out so as I said earlier as it seems to work why mess with it?
 
Bullet construction and strength clouds the issue to make it harder. For example I stopped using a load in my 6.5x55 using the Hornady 160 Grn RNSP on Roe Deer as it was too brutal. probably be fine on Fallow bucks but it ruined a whole shoulder, it jellified it, and the 6.5x55 is not a speed king with that bullet. Range was 90 paces to that was not the issue. It might have been a one off but I was not going to risk it again on the Roe Does.

My old stalling mentor claimed that bullets exiting the muzzle about 2800fps did best, caused less carcase damage yet killed cleanly, God only knows how many deer he had taken in his career and life and been witness to many ............................ many more and what's more in my own limited experience this seems to work out so as I said earlier as it seems to work why mess with it?

Wow. That disqualifies so many cartridges I've used to kill deer it ain't funny.~Muir
 
Muir he was talking about modern bullets not cast Boolits ;) having watched clients arriving and using such things as 7mm magnums, 25-06 with 100 grain factory loads etc on Muntjac and Roe he came to the conclusion for the sort of woodland ranges encountered on his land that any normal cup and core bullet leaving the muzzle at 2800fps just worked and did not wreck the carcase either.
 
Muir he was talking about modern bullets not cast Boolits ;) having watched clients arriving and using such things as 7mm magnums, 25-06 with 100 grain factory loads etc on Muntjac and Roe he came to the conclusion for the sort of woodland ranges encountered on his land that any normal cup and core bullet leaving the muzzle at 2800fps just worked and did not wreck the carcase either.

I figured as much but really isn't that one sided logic? At woodland ranges any bullet at 2800 fps should kill deer quickly. No surprise there! I'm just saying that he chose to generalize about a ballistic circumstance that is/was highly weighted towards his inevitable conclusion: Like saying a 5lb hammer will always kill the fly you hit with it while glazing over the fact that a 6 oz swatter will usually do just as well. He's 100% correct, mind you, but in my opinion it's just not too hard to reach that conclusion.~Muir
 
I figured as much but really isn't that one sided logic? At woodland ranges any bullet at 2800 fps should kill deer quickly. No surprise there! I'm just saying that he chose to generalize about a ballistic circumstance that is/was highly weighted towards his inevitable conclusion: Like saying a 5lb hammer will always kill the fly you hit with it while glazing over the fact that a 6 oz swatter will usually do just as well. He's 100% correct, mind you, but in my opinion it's just not too hard to reach that conclusion.~Muir

Muir you forget that cast bullets are not the norm especially for hunting here in the UK. I'll wager that there are those on this site even that would not consider them legal for it. I would never mention cast and hunting with them to a Firearms Enquiry Officer a sit would surely lead to an argument as the legislation makes no specific mention of them that I recall. If I am wrong I am sure some kind soul will remind/enlighten me :D.

I'll also bet a lot of FEO's don't even know you can make your own bullets like this. They expect shooters to buy them from a shop so they can check up exactly how many you have purchased and used. Making your own will confuse the heck out of them and they don't like that one little bit.
 
with lighter bullets would cast be legal Kevin as they have a velocity limit and would fll short on energy??

We tend to think that cast bullets are limited to low velocities but in fact this is not the case. There are those who drive cast bullets at well over 2000fps and if one gets into the paper Patching realm then 2700fps in a 30 cal is not out of reach. Muir can probably fill you in better than i can as I wa sonly just looking at the cast and paper patching route.
 
Gad! Such low hanging fruit!! Brit is right. Some guys paper patching 300 Win Mag loads clip 3000 fps with 150 grain bullets getting 1.5MOA for a norm. I personally shoot 57 grain cast bullets at over 2700 fps from my .222's and .223's and have hit 2900 fps with a 22-250. Cast bullet shooting is much misunderstood. Velocity is not a limiting factor: Pressure is. If you have a chamber pressure that exceeds the strength of the alloy, you will get poor accuracy and leading. If you load to the pressure the alloy can stand, then you have the potential for a good, usable load. The load that gave this 60M iron-sighted 8x57 group, using a only a forehand rest, fires the 206 grain bullet pictured at 2400+ fps. ~Muir
8x5760Mforehandrest.jpg


(And yes, it's taken deer. Think that would cause your Officials to fluster??)
 
(And yes, it's taken deer. Think that would cause your Officials to fluster??)

Sadly Muir yes it would give them fits in most cases. You see there is no nice paper trial for them to follow and the thought of you making your own bullets would give most of them palpitations. They would be thinking of ammunition manufacture and you really don't want to know the stupid restrictions that would entail.

Once you step outside the little box them place shooters in your in another world entirely. The hassle we had to get it so I could re-chamber that 7x64 barrel to the 280AI was unbelievable. It took hours to explain to the FEO then the girls in the office and the manager and her deputy when you would have thought once it was laid out to the FEO he could present the information to the FLO (manager) and that would be it ...................................... but Oh no. They seem to think that only a Registered Firearms Dealer (RFD) can do such and once you are granted an RFD ticket it magically makes you a skilled machinist and gunsmith. Without this magic bit of paper one in incapable of doing such feats it seems.

Now part of the problem is the act says bullets designed to reliably expand, without looking up the exact wording but believe that's the gist of it ;), now of course the usual numpties wrote this piece of legislation without knowing much about about bullets or shooting. As many know is some particular circumstances bullets designed to expand do not do so and at other times they expand too rapidly. The problem this brings with cast bullets is that these people do not understand how a solid lead projectile can expand and perform properly after all it's solid is it not?

They're conditioned to expect a jacketed bullet, one that is covered in copper or gilding metal.

Despite the fact that they are paid to administer the licensing system they are not expected to know anything about guns or shooting. Hand loading :shock: I expect there are those Firearms Enquiry Officers who do not even know this may be done.

Casting bullets ................................................... forget it ........................................................ probably a handful of them in the whole country know anything about it.

I foolishly mentioned that I would start casting my own bullets to get around the lack of supply of suitable 9.3mm bullets and the disbelief and statements that it's not legal etc had to be seen and heard to be believed.

We believe that is why they spent several hours searching the workshop for evidence of gun and ammunition production. Of course all they found was the cut up old .270 barrel taken off the BSA Monarch when the new 7mm/.280 barrel was fitted and chambered. As the chamber had been cut away( I sawed half one side of it away so it was a cut away) so the barrel was destroyed as a barrel and so attested too by the FEO there was nothing to find they still took the barrel away and tried to claim is was held not on licence but that was dropped as it was a lie and they knew it.
 
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