I think there have been some good points make so far. I think most of us are looking at this from our personal experience which is more than most boffins do. I agree that for future conflicts a modular system should be the way to go. Having said that my understanding of weapon design was that you first choose a calibre and then build a weapon around it. I would go one further, start by working on designing a round with good terminal effects. It is an irony that we have the ability to make given calibres much more effective but the lawyers have deemed these bullets 'inhumane'. I dont suppose that having to pump four or five rounds into someone is that much more humane than hitting him with a good expanding round. Maybe we should ensure that those that argue against expanding ammo are themselves sent for a wee stint on alead swapping holiday.

Whilst a system that is easy to teach is highly desirable, beancounters will take that a different way and reduce life firing on the grounds of not being required due to ease of use. Nothing on this planet replaces live firing both on a formal range and a field firing environment. The more the better.

It is interesting that the drawings showing the effects of various rounds on ballistic gelatine have shown up. Probably the most difficult area of ballistics to study scientificaly is terminal ballistics. It is after all deemed in bad taste to test your ammo on live people. The way around this problem is to use ballistic gelatine, it gives us a material which we can replicate and is reasonably close to human flesh in its density. High speed photography then lets us see the temporary cavity and of course people then assume that that area is destroyed tissue. Unfortunately most tissue (with the exception of the brain and liver) can accomodate that expansion due to natural elasticity. The real damage is confined to a much smaller area unless the bullet hits bone and 'snowstorms'. The trouble is that two rounds of the same batch fired into flesh will never behave the same way.

Some countries have tested ammo on live pigs. Pig flesh is very similar to human and gives quite good although sometimes unpredictable results. Anyone who has seen footage of these tests will be amazed at how little damage is done when flesh alone is hit by HV. Wounds, when opened for debridement are not as impressive as you might expect from the results in ballistic gelatine. Expanding bullets of a similar cal on the other hand produce very messy confused wounds which are much larger than the FMJs.
Its a huge subject that many learned folks cannot agree on. Trouble is that whilst they debate the various aspects they usually ignore the guy who has used his musket in anger and who has seen the terminal results: not on the operating table or morgue but before, during and after the shot(s).

Originally Posted by .338lapua_magnum

I think there have been some good points make so far. I think most of us are looking at this from our personal experience which is more than most boffins do. I agree that for future conflicts a modular system should be the way to go. Having said that my understanding of weapon design was that you first choose a calibre and then build a weapon around it. I would go one further, start by working on designing a round with good terminal effects. It is an irony that we have the ability to make given calibres much more effective but the lawyers have deemed these bullets 'inhumane'. I dont suppose that having to pump four or five rounds into someone is that much more humane than hitting him with a good expanding round. Maybe we should ensure that those that argue against expanding ammo are themselves sent for a wee stint on alead swapping holiday.

Whilst a system that is easy to teach is highly desirable, beancounters will take that a different way and reduce life firing on the grounds of not being required due to ease of use. Nothing on this planet replaces live firing both on a formal range and a field firing environment. The more the better.

It is interesting that the drawings showing the effects of various rounds on ballistic gelatine have shown up. Probably the most difficult area of ballistics to study scientificaly is terminal ballistics. It is after all deemed in bad taste to test your ammo on live people. The way around this problem is to use ballistic gelatine, it gives us a material which we can replicate and is reasonably close to human flesh in its density. High speed photography then lets us see the temporary cavity and of course people then assume that that area is destroyed tissue. Unfortunately most tissue (with the exception of the brain and liver) can accomodate that expansion due to natural elasticity. The real damage is confined to a much smaller area unless the bullet hits bone and 'snowstorms'. The trouble is that two rounds of the same batch fired into flesh will never behave the same way.

Some countries have tested ammo on live pigs. Pig flesh is very similar to human and gives quite good although sometimes unpredictable results. Anyone who has seen footage of these tests will be amazed at how little damage is done when flesh alone is hit by HV. Wounds, when opened for debridement are not as impressive as you might expect from the results in ballistic gelatine. Expanding bullets of a similar cal on the other hand produce very messy confused wounds which are much larger than the FMJs.
Its a huge subject that many learned folks cannot agree on. Trouble is that whilst they debate the various aspects they usually ignore the guy who has used his musket in anger and who has seen the terminal results: not on the operating table or morgue but before, during and after the shot(s).

In fact the recipe for ballistic gelatin was invented many moons ago by calibrating it against tests with live pigs. Gelatin is clearly not the same as the real thing, but the performance is close enough that there is really no need to conduct this sort of live animal testing any more.

Also, if you look at the wound profiles they show both the permanent cavity (dark shaded areas) and the temporary cavity (outer line). As you say, the temporary cavity is really 'just a splash' and is pretty unimportant unless it connects with something incompressible (like the liver).

All in all, it's a pretty horrible subject, but as Ex-Stab pointed out before, an effective military small arms ammo has to be a compromise between reasonable terminal effects and penetration through cover.

Live pigs are still used as the longer term effects (post surgery) can be studied. It also allows certain people to practice primary debridement of wounds etc. Not legal in this country though!

gimme anything 7.62 please i wanna know they aint gonna get back up when i shoot em.
On a serious note though i have a personal weapon here were i live in our armoury that is a modified m16, does the job as many a towel head can contest too

Perhaps we need to step back a bit and look at the range of SAA calibres we need..

I can see around four calibres in an ideal world...

1. Short range up to 200m - from pistol to police carbine. We need a compact weapon design - good knock down (with body armour?) low building penetration option to minimise collateral damage.

2. Rifle/LMG calibre. Standard grunt round. Good cover penetration out to around 800m.

3. MMG/Sniper calibre. Crew served MG and sniper rifle with buffer. Range out to 1500m with laser R/F.

4. Vehicle-Sanger cannon/Heavy sniper. Anti material out to 1500. Capable of firing fuzed projectiles and sabots. Possible secondary AA role.

My openers are:

Light - 4.6x30 mm
Rifle - 7mm - take your pick really - though a 7mm version of the PPC might be interesting...
MMG - 8.6 x 70 (.338 LM)
Cannon 20 x 83.5 (Denel)

Although to be honest, my personal preferences would be:

Light - .455 Webley
Rifle - .577/.450 Martini Henry or .280 Ross
MMG - .55 Boys
Cannon - 2pdr Vickers

But that's just me... :D

Originally Posted by Gun_Nut

Originally Posted by Flying Felix

Or showing 5.56 mm SS109.

M855 shown is the US version of NATO spec SS109.

Am I allowed to tease an ATO for not knowing that?

Tease away :D
It's been a few years since I've worked closely with small arms ammo.

Although to be honest, my personal preferences would be:

Light - .455 Webley
Rifle - .577/.450 Martini Henry or .280 Ross
MMG - .55 Boys
Cannon - 2pdr Vickers
:D :D :D

Coming back to the ballistic tests, they all seem to have the bullet travelling at muzzle velocity rather than a 100/300/600m velocity. The test seems more suitable for comparing pistol cartridges.

Another point that I think is wrong is that they show effects in 60cm of solid gelatin. People just aren't made like that. The depth of expansion for most of those rounds would be in the chest cavity or lower abdomen (not much like gelatin) or in the far side of a thigh. In arms or lower legs, the main cavity would not occur. I think that in most cases a head shot would be incapacitating irrespective of penetration.

Originally Posted by EX_STAB

Coming back to the ballistic tests, they all seem to have the bullet travelling at muzzle velocity rather than a 100/300/600m velocity. The test seems more suitable for comparing pistol cartridges.

Another point that I think is wrong is that they show effects in 60cm of solid gelatin. People just aren't made like that. The depth of expansion for most of those rounds would be in the chest cavity or lower abdomen (not much like gelatin) or in the far side of a thigh. In arms or lower legs, the main cavity would not occur. I think that in most cases a head shot would be incapacitating irrespective of penetration.

Good point and I have seen animals with serious wounds that would kill humns get up and run!
The point of expanding ammunition is to expand substantially on contact and retain enough mass to create a substantial wound channel taking out the engine room on the way!
There is no reason legally beyond the Govt and MoD being weak kneed for us not to use expanding ammunition. The down side of this is when your target decides to hide behind cover which expanding ammo wont penetrate.
Good fmj is the way ahead unless for a specific task you can be sure of targets in the open but then we have people to do that for us dont we?
I do like the 2 pounder idea!
I also disagree that gelatin is a suitable cover all for every test, it should be only a few inches deep and have bones and snot inside it, it also should be fired at from 300 yards!

Agree with above.

Now, if we can get high speed real time x-ray and a dozen chavs………