Forgive me, ideal assault weapon round

[glock glockler]

Lately I've been thinking about a 7.62 Russian necked down to a 100 grain 6mm. I'm not exactly what velocities you could get with such a round, but it'd probably have FAR better penetration than the 5.56 and much better range then the 7.62 Russian.

How do you think this would do? What would be your ideal round?

[Jim Watson]

They call it the 6mm PPC.

Benchrest shooters been using it for some years, but with lighter bullets. Ought to do just fine in mil-spec. There were some experimental 6mm and .25 caliber rounds for SAW but they were not considered worth the trouble of supplying another caliber in addition to 5.56 and 7.62/.308.

In Ackley's book, Col Frank T. Chamberlain said the most destructive wounds were from a .256 (bore diameter in the terminology of the day, 6.5mm bullet) with a 125 grain flatbase at 2700 fps; in comparison with .30-06 and .276 Pedersen. I have never read about it anywhere else.

[Sylvilagus Aquaticus]

I've not had any problems with 6.5x55. 139 grains moving at 2700 or so fps will do quite a number on either a 300 lb boar or a 4 foot circumference pine tree. Ljungmans, when you can find one, make it a little quicker for follow-up shots than a long ol' Swede.

Regards,
Sylvilagus.

The only time I'll turn the other cheek is when I moon the corpse.

[DARTH 44]

I agree with glockglocker that the Russian case,would be best
for the ideal intermediate cartridge to replace the 5,56x45.
I`d neck up the 6mm PPC to take 6,5mm/.264 bullets,or
neck down the 7,62mmx39 again to 6,5mm/.264

.264 bore is exactly in the middle between .224 and .308,plus
.264-caliber bullets have better Ballistic Coefficients than .22s
6mms,25s and sometimes even 27s.

The new cartridge would be cost-effective as many of the
existing 5,56mm rifles could be converted to it.
There are M16s in 7,62x39,aren`t they?

Do a search on "ideal military cartridge".You`ll find many
interesting posts.

Regards

[Glock4ever]

I think the AR-10 in .243 is the ideal battle rnd. I mean it has good range, knockdown power, and light recoil.

[glock glockler]

Sylvilagus,

I think the 6.5 Swede might be a tad long for an assault rifle round, the 6mm PPC would be far more compact and efficient.

Darth,

Isn't the ballistic coefficient determined by the design of the bullet as opposed to the caliber? I think a boattail 6mm would have a better BCO then a flat lead tipped 6.5 mm.

[mcshot]

I think the 6mm SAW round as developed by the US army in the 70s and discussed here, IIRC, would be best.
Have an AR10A4 in .243 but not sure that would be the best for a number of reasons.

[Christopher II]

DSA is producing SA-58 FAL clones in .260 Remington (in limited numbers.) 140grn at 2750fps for 2351 pound-feet at the muzzle, zero at 250 yards and you're within 4" out to 300. At 500 yards, you're only down to 1955fps and 1188 pound-feet. This is fantastic performance, folks. Only disadvantage is the excessively large casehead diameter. But it's available here and now.

- Chris

[DARTH 44]

Glockglocker,
Of course,the BC IS determined by the design of the bullet.
I meant bullets of similar design,but in various calibers.
Like here:
.224 cal 53grs BarnesX - BC 231
.243 cal 95grs BarnesX - BC 398
.257 cal 100grs BarnesX - BC 401
.264 cal 120grs BarnesX - BC 441
.264 cal 130grs BarnesX - BC 479
.264 cal 140grs BarnesX - BC 522
.277 cal 120grs BarnesX - BC 406
.277 cal 130grs BarnesX - BC 428
.277 cal 140grs BarnesX - BC 462
Or here:
.224 cal 77grs Sierra HPBT - BC 362
.243 cal 107grs Sierra HPBT - BC 527
.257 cal 100grs Sierra HPBT - BC 394
.264 cal 140grs Sierra HPBT - BC 535
.264 cal 142grs Sierra HPBT - BC 595
.277 cal 140grs Sierra HPBT - BC 366
.284 cal 130grs Sierra HPBT - BC 395
.284 cal 150grs Sierra HPBT - BC 450

Data from Barnes` and Sierra`s websites.
I know,the military won`t use hunting or target bullets,
but IMO the .264 caliber would be the best option for a
new intemediate cartridge.

Hmmm....wait a minute.Aren`t US troops using 77grain 5,56mm
ammo in Afghanistan,because of lousy performance of
the M855 on ragheads?

Regards

[Spectre]

I assume you mean 7.62x39, sometimes called 7.62 Russian Short (which is interesting, because there are 3 common 7.62 rounds, x25mm, x39mm, and x54mm). If you do a search on this using my name and/or sensop, you'll find there are some of us who really support the basic concept, and probably more justification for using a round like this.

[0007]

A friend of mine in Western NY has a bunch of 6mm/45(?) uppers that he made up for the Japanese market - they can't have military caliber rifles there. The sale fell through and as far as I know he still has them. If you want his email let me know. He's a precision high power shooter and knows what he doing with these things.

[MLC]

FWIW those fellas aren't so happy with the 77 grainers either.
I read a review on the SPR and they had been achieving long range(6-700 yard) hits on targets but were displeased with the lack of lethality. 5.56 just isn't a long range round for anything larger than 40#'s.
BTW is raghead a sociological term?
Like okie, meshback and hillbilly?

[DARTH 44]

"Those fellas aren`t so happy with the 77 grainers either"
One more reason to introduce a new assault rifle round

"..is raghead a sociolgical term?"
To be honest,I don`t know.I was trying to find a nickname for
the talibans,you know,they all wear rags wrapped up around
their heads-hence ragheads.

If we can get a little off the thread for a moment,what is
okie,meshback and hillbilly?

[Sylvilagus Aquaticus]

g.glockler;

Yes, you're absolutely correct on the length; it's a matter of perception as the Ljungmann is long obsolete as a practical weapon for field issue. Noone in their right mind wants to carry something the size of a Hakim anymore...let alone a Garand. However, 6.5 is wonderfully efficient in ballistic coefficient and sectional density. Loaded to 2700 fps or better in 140-160 grain bullet weights it'll dig a wide, deep hole. Even the old Swede cartriges can bore a hole through a Scandinavian moose from stem to stern. If it's tactial penetration you're after, don't discount 6.5 as a possibility.

BTW, I think .223 is pretty spiffy if your bullet weight is heavy enough for longer distance. If I have to 'tactically' shoot long distances, I'll bring out the 30-06 or better.

Regards,
Rabbit.

[Poodleshooter]

A 6mm PPC or 6x45mm is an interesting idea, but all of the ideas for .308 based cartridges are a waste of time. Even a .243 is only going to be about 50grs lighter per round than a .308, while taking up the same space in a magazine, belt or ammo can. To give you an idea, 10,000rds of .243 would weigh only 71lbs less than 10,000 .308. (think about how heavy that last case of .308 was!) 7mm-08 and .260, while awesome cartridges, would save almost nothing weightwise, as their standard bullets run in the 120-140gr range-only 7-10grs less. You save much more weight by shrinking the case and powder charge.
Best idea is to issue more designated marksman rifles that use the same ammo as the platoon level general purpose machinegun-.308.

[glock glockler]

Ok, suppose we go with the 6.5mm bullet instead of the 6mm, what kind of weights and velocities would be possible with the 7.62 Russian case with a 20 inch barrel?

[Art Eatman]

"Assault" rifle, to me, means closer shots than expected from a "Battle" rifle.

Further, military doctrine for an assault means following a curtain of artillery fire. U.S. doctrine is that the spacing be some 200 yards; other countries have used closer spacing--some as little as 50 yards.

The AK round, as is, seems adequate for the shorter spacing, but marginal for U.S. doctrine. For 200 yards, inherent accuracy of the rifle comes into play.

From this, I'd guess that a 7mm of 140 grains from about a 42mm to 45mm case might be an answer...

FWIW, Art

[Kharn]

To chamber an AR15 in 7.62x39 requires a very thin wall on the sides of the bolt that surround the case head. Thats not a very good idea for a true military weapon.

Kharn

[0007]

And don't forget the TCU 7mm/223. I had one in a Martini action. Changed it only because I didn't want to get into reloading another round...

[Sylvilagus Aquaticus]

Glockler, I think that'd be pretty much akin to JD Jones' 300 Whisper based family.

http://www.sskindustries.com

http://www.sskindustries.com/cartridges.html

Whispers®: 6mm, 6.5mm, 7mm, 300 and 338 #2.




Regards,

Rabbit

It must be admitted that God made women only to tame men. - Voltaire, Ingenuous. 1767.

[Chris McDermott]

Start with the old 25 Remington with it's .420 base diameter, then shorten it to 1.75" to fit into the M16 and use 105 grain bullets with armor piercing hardened steel tips. Probably need about a 1-8" twist to stabilize; but should be good for ~2700 fps and be fairly flat out to 300 meters. The long bullet that is light in the nose results in a destabilization when the bullet hits something that should give good wounding effect. Even if the bullet stays stable, with 30-50% more weight than the 223 it will hit a lot harder than the 223; and the recoil shouldn't be any worse than a 7.62x39 so it would still allow full-auto fire when necessary.

[DARTH 44]

Glock glocker, good question.
I think, with modern powders we could expect muzzle velocities
in the vicinity of 2850 fps for a 90grs bullet~2202 J ,and
2650 fps for a 100grs bullet~2115 J,from a 20" barrel.

It must be noted though,I mean a case of .445" head diameter(7.62X39),but a little longer ,1.6"/41mm and with 30-degree
shoulder angle as opposed to the original Russian case 1.528"
long,and with 18- degree shoulder angle.
I must also add,I assume the abovementioned data for a
cartridge of maximum 2,26" OAL(.223 Rem) so the existing 5.56mm rifles could be converted to it.

To sum it up,I`d say my 6.5mmX41 could achieve even better
ballistics,but to do so it would have to be loaded to 2,55''-2,6"
OAL and with 120-140grs bullets.That would require a longer
magazine and would significantly raise the costs of introducing the new cartridge though.

Regards

God bless the victims of 9 11 01
We`ll never forget.

[benewton]

Anyone interested in the 6x45 .223 wildcat?

Seems like a worthwhile increase in performance over the 5.56 while utilizing the standard mags and lower.


Got no time to develope a new rifle, but I do handload, and am thinking that updating the old is a good idea.

[Spectre]

gglockler,

A search for "7.62 Russian" turns up this. This may seem pedantic, but we are losing our rights, partially because of incorrect terminology used by the media when describing what we have. As lawful gun owners, we have a responsibility to have a reasonable knowledge, especially when we have the resources to gain that knowledge.

benewton, you may find this information from the Reload Bench website helpful.

Some feel that a cartridge similar to the 250/3000 Ackley Improved is the "new" cartridge our military needs. I agree.

[Christopher II]

Any new round based on the .223 or .221 case is going to be greatly hampered by overall length limitations. No matter how you repackage it, a 45mm case is going to top out at around 1700fpe. That ain't enough for an infantry rifle.

Since we're (sorta) designing a new round, why not a new rifle to go with it? Why hamper ourselves trying to shoehorn a new cartridge into an old weapon system?

The .25 Remington would be an interesting way to start. The small casehead would allow for more rounds in a magazine, and if you stretch the case to 50 or 51mm you could crank out a 140grn 6.5mm bullet at around 2700fps. 2800fps would be better (equalling the .308 ballistics but with better downrange energy and flatter trajectory.) All this with a lighter case and less powder.

Another option would be to stick with a short case, beefed up to handle higher chamber pressure, and switch to a non-nitro-based propellant. Hmmm....

- Chris