Cased Telescoped Ammunition?

[WARFAB]

I noticed an article about the military developing a replacement for the M16.

http://www.foxnews.com/tech/2017/05/...gger-ammo.html

This is the first I've really heard of or looked into CTA ammo. As a service rifle competitor, I can't help but wonder how accurate this type of cartridge will be. Most competitors are extremely concerned about controlling the seating depth of the bullet to make sure it has a consistent and short jump to the lands. Some people hand load so that the bullet is actually seated in the lands once chambered. Having the bullet sitting inside the cartridge with a huge amount of jump to get to the lands seems like it would cause some accuracy problems.

Edit: If this is intended to lead to plastic cases, will politicians start throwing our money at the idea for reasons other than giving our troops the best weapon possible? A comment from a random internet observer:

As for all that brass turned in, we have to manage it, package it, and then sell it for what it is at DRMO sales. That is a lot of administrative overhead. It is also a source of brass for large scale reloaders, which means it will dry up immediately. There will be no brass to reload, and the anti gun politicians immediately get a win in their column there. There won't be any subsidized surplus to support the MSR ammo needs. LSAT is right up their alley - it's an intended consequence and one they quietly support.

[Liberty's Teeth]

Why don't they just take the AR10 platform chambered in 7.62 X 39? Best of both worlds, awesome firearm and a little lighter round than the 7.62 X 51. The 7.62 X 39 can be found in every nook and cranny including downtown ChiTown.

[WARFAB]

Not as much money for special interests if they do that?

[Meketrefe]

The army will never adopt the creedmore, grendel or any other cartrige with a 30 degree angle shoulder. No Army has ever done that.
Also something like the 6.8spc case in 6mm or even a tad larger will give more with less weight, size and powder increasing
this way the firepower vs anything with a .743 bolt face.

[WARFAB]

What's the technical explanation for not adopting a 30 degree shoulder cartridge?

[Ham_Chu]

*yawn*

then came THIS replacement...

M16 series has been longest running rifle in US Army service....why change now...just make the A6...or whatever

EDIT.....hot off the press......this should settle it all:

Trump weighs in on new Army rifle

[Meketrefe]

What's the technical explanation for not adopting a 30 degree shoulder cartridge?

They are "tight" chambers that is low taper and the shoulder angle doesn't allow them to run efficiently in fast loading devices including feeding belts.
This is a huge design directive for military cartridges. They have never made it to the trials. Think about it, no once a single service cartridge has ever made it in any army / military in history.
Do you know of any? ...maybe I missed this.
BTW, the Grendel is 28 degrees but for all intents and purposes is the same as 30 and will not work. what is ok for sporting purposes even some special purpose platforms has nothing to do with with the rigors of MBR and service rounds.

When the people say the AK47 is so popular and reliable is not only that... look at the original cartrige.. it was originally designed to be made of steel,
to run like that, and the rest built around the cartridge. Loose fit, taper, shoulder angle... these are directives for the purpose.
Even our current 5.56 follows similar directives, it is just the quality is superior with tighter tolerances and to be made of brass and not steel.

so the creedmore is just more of the 6.5 marketing BS. It is not happening no matter how enthusiastic the marketing guys and 6.5 evangelists get.

the 260 could make it but the case volume to bore volume ration is disproportional to get the most out of shorter service barrels.

The 7mm-08 is superior to the 308 and 260 & creedomore in every single way. Better ballistics, more momentum with a flatter trajectory and more reach
than those others.
But no matter how good the 7mm-08 the change from the 308 parent cannot be justified.
The 6.5 maxes out at 140grains. While energy will be sufficient momentum will not. This is where a 7mm with 150 to 175 gr bullet will make the difference.
There is a reason the best bullets in the 308 are the 175gr sniper ammo. That momentum is needed for military.
In tactical / practical matches the 6.5 might get more hits but it can also fail to score heavy steel gates due to the lack of momentum. Of course we can accommodate steel targets for sporting use but in real life we cannot do that.

[dwa12479]

Good info as alwaya, thanks Meke.

[Hunter]

I volunteer to dispose of all the outdated M-16's.

[Hunter]

Why don't they just take the AR10 platform chambered in 7.62 X 39? Best of both worlds, awesome firearm and a little lighter round than the 7.62 X 51. The 7.62 X 39 can be found in every nook and cranny including downtown ChiTown.

7.62x39 doesn't require the AR-10 lower and makes damn fine AR-47 for deer blasting.

[Meketrefe]

7.62x39 doesn't require the AR-10 lower and makes damn fine AR-47 for deer blasting.

Yes. The biggest issue with the AK original round has been the lack of ,450 strong bolts that could take the additional thrust but now this
has changed and many makers have beefed up bolts with rounded edges around the base of the lugs that give an additional 25 to 30% strength
vs. the original 7.62x39 bolts for the AR15.
While light-for-caliber cartriges like the 7.62x39, whisper/blackout, 30 carbine and a few others have been faced out by more efficient and deadly
cartriges the advantage of the 7.62x39 is that it can be reloaded with quality brass and pumped to have more power than the other 30 calibers.
The extra case capacity makes a big difference. Aside from the cheap service ammo there is some specialized hunting ammo that delivers
more momentum and makes a huge difference vs. the blackout and 30 carbine. Specially with the modern firearms and brass that can take the
additional pressure w/o any issues what so ever.
For example I use 7.62x39 lapua brass for my 35 gunner and I pump it close to 50Kpsi w/o any ill effects in the bolt or brass. Hornady brass
is not as good but also very nice specially the grendel as donor. Also nice because of the small primer. Lapua grendel also makes a great
brass for the x39 or any wildcats.
So in this case, and unlike the 30 carbine and blackout that are severely handicapped by the lack of case capacity, with the x39 one has the option
to go from cheap steel ammo for burning loads and practicing to load some premium loads that put the round half way between the blackout
and a 30-30 in terms of power and momentum on the target.
It will not be as effective as other cartriges like the 6.8 but it will be a decent choice taking those considerations.
Also with good rifles like the little howa or CZ and quality brass it can be very accurate in line with Bench Rest type of accuracy but that
is not what the cartrige was intended for originally.
What kills the low SD cartriges is the lack of speed. There are also die sets that will ship with two expanding buttoms for the x39 so one
could load 308 caliber bullets.
Keep in mind that the 7.62x39 reload can put a 110gr bullet to 2600fps from a compact carbine whereas the 30 carbine and blackout
will struggle to make it past 2300fps. Not a huge thing but something to consider.
Also the 7.62x39 has enough capacity to propel a 150gr soft point to a decent speed for extra killing power at moderate ranges.
Something the other smaller 30 calibers cannot do.
So while the 7.62x39 is phased out might not be a horrible choice considering everything and if one wants to hunt with certain authority
at moderate ranges.

[Ham_Chu]

I volunteer to dispose of all the outdated M-16's.

Those(M16A2's) have already been taken care of. ISIS has steadily procured them from the Afghan and Iraqi militaries over the last decade or so.