02-20-2013, 11:04 AM
A few points on the (in)effectiveness of 5.56 mm
This appears to be a more controversial subject than it needs to be. Based on the analysis of combat reports from the USA, UK, Germany, New Zealand, Australia and other ISAF units in Afghanistan and to a lesser extent previous experiences in Iraq, the following issues are accepted:
1. M855 5.56 mm NATO ammunition is most effective below 300 metres. Improved M855A1 EPR 5.56 mm ammunition is most effective below 500 metres. That's fine, because 5.56 mm was always designed to perform best below 500 metres. However, the theory that 90% of infantry engagements take place at ranges below 300 metres has now been debunked. UK data relating to Afghanistan states that more than 50% of combat engagements take place at ranges above 300 metres out to a maximum distance of 900 metres. This was true in Kosovo, the Falklands and several other Cold War era skirmishes.
2. It is true to say that most of the killing both with 7.62 mm and 5.56 mm ammunition is still done at ranges below 500 metres, but infantry small arms have another vital role to perform: suppression. Very often it is extremely difficult to pin-point an enemy position, therefore suppression is required to fix the enemy in place while other units manoeuvre into an assault position or supporting air assets or artillery fire is called in. 5.56 mm has a significantly reduced signature versus 7.62 mm (and 6.5 mm Grendel for that matter) so you must miss much closer to an enemy to have a suppressive effect.
3. M855 5.56 mm is highly susceptible to wind drift. On a range at sea level in lab conditions, it is entirely possible to hit a target at 600 metres - even 800 metres if you are a crack shot - but in the mountains of Afghanistan with a gale blowing it can be difficult to hit targets at 200 metres. It is a 4 MOA ammo.
4. M855 5.56 mm is highly susceptible to intermediate barriers that may obscure a target, such as car windscreens, wooden door frames, light masonry and thick foliage. The increasing use of body armour is also an issue.
5. In terms of terminal effectiveness, the yaw characteristics of 5.56 mm are dependent on striking velocity and angle of attack. The only way to increase terminal effectiveness is to ensure the projectile fragments. Soldiers have reported repeated instances of through-and-through shots that do not cause sufficient wounding to incapacitate.
6. Any unit equipped only with 5.56 mm weapons, will be overmatched by an enemy using full power weapons and ammunition. The Taliban has been using Russian-made PKMs and SVDs to engage ISAF units at ranges whether the latter cannot return fire. This happened time and again from 2006 and until 7.62 mm weapons were readopted at squad level.
All of these concerns should we well know to forum members here. They're reason why the US army developed the M855A1 EPR. Even though the the EPR is better, it still isn't a match for full-calibre ammunition 7.62 mm and above.
Personally, I tend to agree with Cory here. I think that 5.56 mm is useless in anything other than a PDW / SMG role. I'd love to see 6.5 Grendel adopted across the board - it would be a much better solution even though it cannot be a standalone round. The only issue I have about Grendel uppers slotted onto existing M4 weapons is that they restrict magazine capacity to 25 rounds. A slighter larger receiver and magazine well could allow wider magazines and a 30 round capacity.
The UK Royal Marines want either a new calibre or the wholesales return to 7.62 mm for their next generation weapons.
When it comes to the politics of adoption, it is the Special Forces community who are most driving innovation in calibers and weapons. They like weapons such as the HK417 but are well aware of the weight and recoil penalty it imposes. They frequently fire automatic bursts BTW. Offer them a new round and they'll certainly try it. The .300 Blackout is a prime example. When a new weapon system proves itself it soon achieves a wider currency.
This appears to be a more controversial subject than it needs to be. Based on the analysis of combat reports from the USA, UK, Germany, New Zealand, Australia and other ISAF units in Afghanistan and to a lesser extent previous experiences in Iraq, the following issues are accepted:
1. M855 5.56 mm NATO ammunition is most effective below 300 metres. Improved M855A1 EPR 5.56 mm ammunition is most effective below 500 metres. That's fine, because 5.56 mm was always designed to perform best below 500 metres. However, the theory that 90% of infantry engagements take place at ranges below 300 metres has now been debunked. UK data relating to Afghanistan states that more than 50% of combat engagements take place at ranges above 300 metres out to a maximum distance of 900 metres. This was true in Kosovo, the Falklands and several other Cold War era skirmishes.
2. It is true to say that most of the killing both with 7.62 mm and 5.56 mm ammunition is still done at ranges below 500 metres, but infantry small arms have another vital role to perform: suppression. Very often it is extremely difficult to pin-point an enemy position, therefore suppression is required to fix the enemy in place while other units manoeuvre into an assault position or supporting air assets or artillery fire is called in. 5.56 mm has a significantly reduced signature versus 7.62 mm (and 6.5 mm Grendel for that matter) so you must miss much closer to an enemy to have a suppressive effect.
3. M855 5.56 mm is highly susceptible to wind drift. On a range at sea level in lab conditions, it is entirely possible to hit a target at 600 metres - even 800 metres if you are a crack shot - but in the mountains of Afghanistan with a gale blowing it can be difficult to hit targets at 200 metres. It is a 4 MOA ammo.
4. M855 5.56 mm is highly susceptible to intermediate barriers that may obscure a target, such as car windscreens, wooden door frames, light masonry and thick foliage. The increasing use of body armour is also an issue.
5. In terms of terminal effectiveness, the yaw characteristics of 5.56 mm are dependent on striking velocity and angle of attack. The only way to increase terminal effectiveness is to ensure the projectile fragments. Soldiers have reported repeated instances of through-and-through shots that do not cause sufficient wounding to incapacitate.
6. Any unit equipped only with 5.56 mm weapons, will be overmatched by an enemy using full power weapons and ammunition. The Taliban has been using Russian-made PKMs and SVDs to engage ISAF units at ranges whether the latter cannot return fire. This happened time and again from 2006 and until 7.62 mm weapons were readopted at squad level.
All of these concerns should we well know to forum members here. They're reason why the US army developed the M855A1 EPR. Even though the the EPR is better, it still isn't a match for full-calibre ammunition 7.62 mm and above.
Personally, I tend to agree with Cory here. I think that 5.56 mm is useless in anything other than a PDW / SMG role. I'd love to see 6.5 Grendel adopted across the board - it would be a much better solution even though it cannot be a standalone round. The only issue I have about Grendel uppers slotted onto existing M4 weapons is that they restrict magazine capacity to 25 rounds. A slighter larger receiver and magazine well could allow wider magazines and a 30 round capacity.
The UK Royal Marines want either a new calibre or the wholesales return to 7.62 mm for their next generation weapons.
When it comes to the politics of adoption, it is the Special Forces community who are most driving innovation in calibers and weapons. They like weapons such as the HK417 but are well aware of the weight and recoil penalty it imposes. They frequently fire automatic bursts BTW. Offer them a new round and they'll certainly try it. The .300 Blackout is a prime example. When a new weapon system proves itself it soon achieves a wider currency.