The Ultimate Combat Round

Status
Not open for further replies.
What about 5.45 necked up to 5.56mm? Use an 82-grain streamlined Scenar-type bullet and shove that puppy at about 3000 f/s.
Click to expand...

I can't help but think that would be a marketable round too. If/when the cheap 5.45 dries up, a case that's slightly different and only requires a rebarrel of the AKs, but has very good downrange potential and uses readily available bullets would seem just the ticket for a lot of varminters.
 
I've got a question for all you ballisticians in the house. What's so great about having a high-BC in a combat bullet that will be most used for 200 +/- 50 yard fire-fights, with most occuring under 200 yards? I can understand the concept in long-range fighting, but in general what's that BC going to do for lethality?
 
Well, I didn't use a heavy bullet, but I am currently working on a wildcat, the 5.7 Czech. This is again based on the 7.62x45mm Czech necked down to 223. I wanted to see what I could do with a 223 length cartridge with a bigger case head. I'm a huge fan of the CZ-527, and wanted to see how fast I could push a 223 bullet and still have the round fit in the CZ-527 action.

The resulting cartridge achieves near 22-250 performance with AR safe pressures.

5.7cz.jpg


This was not meant as a combat round, but rather as a superior varmint round for small action rifles like the AR-15, CZ-527 and Remington 799. The case is easily formed from 7.62x45mm brass.
 
Deer Hunter

The high BC bullets allow the round to perform multiple roles better. It means nothing in a combat rifle, but if you want to use the same round in a DMR or LMG, it allows you to have high lethality at long range.

This is exactly the advantage that 6.5 Grendel exhibits compared to M80 ball. Even though the bullet is lighter and starts off at a lower velocity, the 6.5 actually retains more energy longer, and exceeds the retained energy of the M80 ball at around 700-800 yards.
 
To add:

Personally, I would load my 6.5mm combat rifle with a bulllet in the range of 105-110gns to reduce recoil and increase energy, and use heavier high BC bullets in DMRs and MG. But for logistical purposes, it makes more sense to have one round that can do it all.
 
I see. So high BC in combat rounds is shoved onto the DMR and LMG class, which right now we're using standard 7.62 NATO? Is there any reason why, instead of finding a new round, simply switch out bullets for the 7.62?
 
As noted, the ideas is to have a single infantry round appropriate for all environments.

If you ascribe to the idea of having one round for rifles and another for MGs, and another for snipers and DMRs, there's no need to worry about a mid range cartridge or high BC bullets.
 
If we're looking for one-round-to rule them all, based on logistics, I would assume that different bullet loadings for the 7.62 NATO would win by a huge margin. No huge changes other than bullet weights of the ammo.
 
If we're looking for one-round-to rule them all, based on logistics, I would assume that different bullet loadings for the 7.62 NATO would win by a huge margin. No huge changes other than bullet weights of the ammo.
Click to expand...

Weighs too much and too bulky. Even if you use a load like Hornady's 110 grain TAP for your service rifle and save a little weight on the round, you've still got to carry that ammo, and 7.62x51 mags just take up more space than intermediate rounds. A smaller basic load is, well, a smaller basic load, with some potential for bad outcomes inherent to it.
 
I know it wouldn't work as well as two calibers, like what we are using now, but looking at it from the standpoint of one-main-caliber, using our pre-existing methods of manufacture, bullets, brass, etc would be better than simply starting from scratch. Then again, I may just be another .308 affectianato. The system right now works just fine.
 
Another advantage for high BC bullets is that they are long, and when entering tissue they may destabilize more quickly and when they start to tumble they will experience more drag, leading to fragmentation more easily than a shorter, lighter, faster bullet. That's why the heavier SMK (I think around 77 grains?) with cannelure actually fragments better than the light 55 grain used before the current 62 grain "penetrator."

At least that's my understanding.
 
The short sharp shoulder casing of the .308/7.62 NATO (compared to the 30/06 and Mauser military cartridges), results in higher pressures for the same velocity once you get past the 144-150 grain bullets.
The Match loading for the 7.62 NATO for example mimics the .303 british Mk.7 in bullet weight and velocity yet requires around ten percent higher pressurs in order to do so.
I suspect this is why they decided to go with a 125 grain ultra high velocity AP round when the 150 grain Nato AP round proved much less effective than the 168 gr 30/06 AP rounds in combat situations.
They couldn't push a heavier AP bullet with that much bearing surface at the same velocities without upping the pressures an inducing velocity variations and pressure spikes.
The occasional pressure spikes may be the root cause of bolt chipping in the M60.

If you have to go to a lighter higher velocity bullet in any case then it makes sense to go to a slightly smaller caliber and better designed case.
 
Neck it up, and blow it out and you have...220 Russian, which in turn begets the 22 PPC.
Click to expand...
I don't think you meant that...according to my info the .220 Russian is based on the same case diamater as the 7.62x39, which is wider than the 5.45x39.
 
I would have to go with the 243 or 260. They are both great rounds and are already proven in lots of competitions, as well as various law enforcement agencies.
 
6.5-250

Been follow this discussion with some interest especially remarks about 6.5mm/100+ gr bullets at 2800 to 3000 fps. The idea has great, and practical merit. While I don't have every answer to case dimensions I have experience shooting 6.5mm, 107gr SMK, at 2800 fps and 142 SMK at 2650 pfs from 6.5-250. The result is very controllable. Recoild is less than 260, 7-08 and 308, greater than 6XC and very similar 6.5 Grendel and 6.5X47.

Many rifle competition events are gravitating to 6/6.5 bullet size and intermediate case volumes. Validation of some of the ideas in this thread. It would be really interesting if anyone has some test data to go with the ideas.
 
I say you all are looking a little to deep into this topic. Re-arming the military is not going to happen soon and new rounds and rifles to shoot them don't grow on trees so were sticking with the 5.45 and the 7.62 NATOs for a good long time to come.

Todays enemies are gorilla fighters, in urban environments, armed with a myriad of weapons and little to no personal armor. That being said, I believe the focus should change from the round to use, to what bullet should be used. As of now, the military uses FMJ rounds, I believe this is the biggest problem with modern rifles.

Anyone who has shot anything with a FMJ .223 round knows how little it is damaged outside of the small hole where the bullet went clean through-and-through. There are 2 very good reasons to change the current ammo to a soft nose or hollow point design:

1) Through-and-through shots in an urban environment are dangerous as hell. You may be shooting at an enemy combatant and using an inhabited house as a backstop thus putting innocent civilians in risk of death. Hollow point or soft nose bullets that can expand in the target help to lower this risk by greatly slowing the round as it expands.

2) Soft point/hollow point rounds are better at stopping a target. Modern wars are fought against radicals whom will happily kill themselves to kill Americans. We should therefore take extra precautions to kill these enemies, not just wound them. Classic wars, such as WWII in Europe were fought by soldiers whom valued life. Upon being shot or injured, these soldiers would stop fighting, being taken away by medics or captured by the enemy. The people we face on the battle field today are different, upon being shot they will blow them selves up to try and kill the friendly soldiers. Care must be taken as these soldiers will fight to the very bloody end and they don't care to live. With this being said, the faster you can KILL an enemy, the less of a chance they have to cause more harm to you. Hollow and soft points do this best as any hunter can tell you.
 
Yeah, I agree with TheGunGuru, except in order to get the bullets I want with 5.56, I have to go outside the OAL of the round. Hence the x39mm carts. I could just bury the bullet in the case really deeply and have a contour neck with improved powders, I suppose.
 
Anyone who has shot anything with a FMJ .223 round knows how little it is damaged outside of the small hole where the bullet went clean through-and-through. There are 2 very good reasons to change the current ammo to a soft nose or hollow point design:
Click to expand...

attachment.php


There's plenty of data out there to suggest otherwise.
 
Well, to be fair, I didn't agree with TGG on that.
But bullet redesign is the most important thing, not a new cart. But I like dreaming...
All of the firsthand accounts of .223/5.56 that I've heard have said it hits like a lighting bolt and kills quickly. Now those were deer, not drug-enhanced terrorists.
 
I have quite a lot of experience with the 5.56 and yes, Dear Hunter and Nolo, the M193 ball ammo can and does "explode" into many pieces on occasion. However the bullets, more often than not, don't fragment like those in the picture. The reason why the FMJ round is used is to prevent such actions and a hollow/soft point is designed to always expand/explode on impact. I just want to stress the point that if I was shooting at un-armored people with a 5.56, I would want a bullet which would always expand rather than hope it hits a big enough bone or has enough velocity to expand. Also keep in mind that the nature of today's war means soldiers are using more carbines than ever, and therefore shooting at lower velocities, all-be-it still about 2900 fps.
 
TGG, thank you for clarification. You sounded to me just like another troll calling the 5.56 a "poodle shooter." Yes, it fragments. But boyhowdy, you want to be sure that sucker fragments.
 
Status
Not open for further replies.

Similar threads

N
  • Locked
Thread Follow-Up: The Ultimate Combat Rifle
Replies
7
Views
760
Nolo
N
N
  • Locked
The Gun Hose
2 3
Replies
71
Views
6K
Nolo
N
R
  • Locked
Growing Popularity of 8.6mm Sniper Round.
2
Replies
30
Views
5K
anymanusa
anymanusa
W
  • Locked
Sooo, would you buy a .50 caliber AR15 ?
2
Replies
28
Views
2K
Okiecruffler
O
N
  • Locked
The Citizen's Rifle
2 3 4 5 6 7 8
Replies
184
Views
10K
Renwyn
R
Back
Top