Military Caliber

[rcmodel]

Over-Bore means pushing a lot of burning powder through a small hole in the barrel.

Neither your 30-06, or .270 are over-bore, although it is starting to get close.
Neither is the .223/5.56.
That is why barrel life on auto rifles & machine guns can be kept at an acceptable level.

A .243 is getting there, and a .220 Swift or .300 Rem Ultra-Mag already got there.

Here is a good read on it:
http://bulletin.accurateshooter.com/2011/04/overbore-cartridges-a-working-definition/

rc

 

[Sam1911]

For an entertaining view of the ragged ends of "overbore," I just took a look at Hodgon's site to compare some 7mms.

The 7mm Rem Mag uses 68 gr. of 4831 to push a 150 gr. bullet about 3080 fps.

Remington's new "Just STOOPID Powerful" 7mm Ultra Mag uses EIGHTY FOUR grains of 4831 to go 100 fps. faster.

A very practical minded person might be excused for wondering if 100 fps difference, equating to an elevation correction difference of a few inches all the way out to 1,000+ yards, is really worth the cost to the wallet, and barrel, and your shoulder, of touching of an extra 20% powder charge.

 

[PandaBearBG]

Cosmo "So what? We're buying the bullets my friend. We're buying the weapons. WE are responsible if the arms and ammo are not doing the job. I'm tired of reading about some excellent young man blown up by utterly worthless scum who should have been shot down long before he had the chance to detonate himself. And I know Hague to be the product of a twisted, archaic society that was rightly destroyed in the fields of the Great War. Unfortunately we are stuck with this vestigial remnant of their very bizarre view of warfare." +1

Our current calibers are fine, Shady rules of engagement, and turning soldiers and marines into cops with shackle tight rules is what is killing our troops. They are fighters, not peace keepers.

 

[ExAgoradzo]

Thank you very much Sam and RW. I am educated.
My next question is a 45-70 'overboar'?
I'm pretty much decided as to that over the 444Marlin, but is the 444 overboar?
I have enjoyed reading both your comments on many topics.
If I'm thread jacking, I appologize.
Thanks again.

 

[Sam1911]

It's a little OT, but I think we can answer it quickly and get back on track:

NO! A .444 or .45-70 are kind of the exact opposite of "over-bore." HUGE hole, big bullet, relatively light charge for the amount of lead you're throwing.

Like a .45ACP, you could probably shoot a .45-70 darned near forever and never wear out the barrel.

 

[ExAgoradzo]

OK, thanks, 'time-in'...
I'm really enjoying this thread.

 

[Shadow 7D]

Our current calibers are fine, Shady rules of engagement, and turning soldiers and marines into cops with shackle tight rules is what is killing our troops. They are fighters, not peace keepers.

A stoopid view of war is: the army's job is to shoot people and let the politicians (and god) sort them out.
The caliber is effective, the tactics work (how well may be questioned) but allowing the guys to go after the people shooting at them (been there done that PM me if you want to discuss it)
would prove to be a more fruitful discussion than debating if a soldier carrying OVER 150 pounds of gear should have heavier ammo or accept the limitation of 5.56.

Oh and on a historic note, infantry tends to engage at 100 meters (~330 feet) or less, and I haven't seen a person here debating the close in performance of 5.56, other than yes there are more effective bullets.

 

[ArtP]

Regarding overbore, my favorite .243 load uses only 36.4 grains 4064 to achieve ~3000 fps with a 70 grain bullet, while the 243 case capacity is listed at 60 grains. In the chart posted way back, it uses case capacity to measure overbore instead of actual powder used in typical loads. In my load book (hornady), all .243 loads top out at forty something grains.

 

[ArtP]

See the funny thing out these topics

THEY ARE ALWAYS BROUGHT UP BY PEOPLE WHO HAVE NEVER BEEN IN THE MILITARY

Why does one have to be a veteran to discuss our military?

I tried to state it, that I have not been in combat, just as the vast majority of us haven't, as to not come off like I knew these things in the discussion as a matter of experience.

 

[ArtP]

Going back to my OP, where I asked if the trade-offs with a larger caliber would be worth the cost in weight, capacity etc., it seems the answer is "no". It has has been pointed out on many different levels here.

Thanks for your thoughts everyone.

 

[d2wing]

Yes ArtP having been in the military does make a difference that civilians will never understand. If you wanted a .243 you should just stay with the .308. To me the opinions of non vets don't count for much. The same thing gets brought up every few weeks.
This is not a new discussion. The answers haven't changed.
Combat is not like anything else including anything you have done or imagine.

 

[Cosmoline]

But if you had the choice, would you or would you not opt to repudiate the expanding bullet prohibition? A prohibition not drafted by vets, but by European diplomats older than our great great grandparents who found the notion of the white infantry using them against other white soldiers distasteful, but had no such qualms about exploding artillery shells.

 

[Slamfire]

I don’t think the .223 was so much developed as it was born and adopted. From a magazine article I read the round was created at Bob Huttons Ranch by a bunch of guys who were looking to push a .22 bullet 3000 fps . They also had a distance criteria. They basically wild catted the .222 Remington. Stoner used it, and that’s how we got the thing in inventory. But it was only a wild cat, you can go to DTIC http://www.dtic.mil/dtic/, type in “Report of the M16 Rifle Review Panel” and see all the various reports created as DoD reacted to all the dead Americans who died with a jammed M16 in their hands. What you see is a rifle and cartridge not ready for prime time. The Department of Defense found to their dismay that this “fully developed cartridge” did not have any of the normal standards defined: such as brass hardness, pressure curve, primer sensitivity, fouling due to primers and powders. Heck, the powder lots used in the early M16 were hand selected. It was beyond state of the art to make all powder lots within the rifle requirements, the contractor had to select the lots that worked. When that contractor told DoD to pound sand on more powder deliveries, that is when we got into the ball powder mess.

The cartridge was just a wild cat created by a couple of guys at Bob Hutton’s ranch in California.

This has an interesting time line of the adoption of the M16

http://www.thegunzone.com/556dw.html

Normal cartridge development would entail a number of factors, each of which has to be traded against each other. You could call it an analysis of trades.

Factors you would trade off: lethality, range, recoil, barrel life, cartridge weight, accuracy, function. Bullet weight and diameter would fall out of the trades.

You have to trade these things off, if lethality was your one and only goal you would end up with some monster that no one could shoot without a nose bleed. How issues are traded is very contentious, because everyone has a “pet rock”.

The 308 was more or less dictated. The Army wanted 30-06 performance in a smaller package. So they had already decided on range, recoil, barrel life, lethality. The only real issues for the 308 were size, accuracy, function.

I consider the7.62 X 39 cartridge a better example of a developed cartridge. I suspect the Russians wanted 30 caliber, but they sure traded size, velocity, weight, range, lethality, recoil, function, to get a really good intermediate combat round.

Something like the 243 would be tossed out early, when the design team finds that barrel life is 800 rounds.

 

[suzukisam]

opinions of non vets don't count for much

their opinions seem to count at the voting booth.. and when they contribute to things like wounded warriors project!!! I'm not a veteran, but I have the utmost respect for our military, and when given the opportunity I will vote for any person or action that elevates our soldiers and military infrastructure... I think you cold have re worded that

 

[HKGuns]

I think the best answer is to use the right tool for the job and there is no single answer to every situation. It is fairly well documented that the .556 could use some help beyond 500 yards for combat effectiveness. In this situation, everyone could likely agree a .308 would serve as a more effective combat weapon, or any of the other larger caliber choices.

However, for house to house, close in combat the 556 appears to be very effective, along with shotguns and other assorted varieties. When these sorts of discussions arise, I think it is very important to talk about the mission.

 

[Shadow 7D]

opinions of non vets don't count for much

Yeah, but they don't count for much when some guy who can't walk 1/2 a mile, let alone do a 30 mile forced march with a combat load, decides to pontificate out what type of gun/ammo/gear/etc.

when they say "walk a mile in their shoes"
well go walk 30 miles, or a 15 mile patrol in 130* heat wearing body armor and full battle rattle AND 80+ pounds in the ruck (before spare ammo)
if you really are interested in what it takes, http://www.bataanmarch.com/
so,

here is a summary, a larger round = more weight AND less ammo

oh, cosmo
don't get me started, a soft lead bullet is legal, but a HP/SP is illegal, yeah, I'm all for getting rid of the bullet ban, besides, it's not like anybody we fight actually is under it or bothers to follow it.

 

[tahunua001]

ok I have not read the entire thread so forgive me if I'm reaping old information but

But the 5.62x45 it seems is the standard caliber

I believe you meant 5.56x45 not 5.62x45, to my knowledge a 5.62x45 has never existed.

second all of the guys that say that 5.56 is too underpowered for a battle rifle are the same guys that say that a 9mm is garbage for a self defense round and a 223 is a bad round for deer.

more police stations use the 9mm than any other round for their issue guns and the 9mm is the most popular CCW round in the world. yes the .40 10mm, 357sig and 45 acp and gap all offer better stopping power but a 9mm will still stop an assailant cold with a single well placed shot. even if you dont manage to kill the BG I will guarantee that he will shift his focus to flight over fight.

the same with 5.56/223. I have killed 200 pound whitetail bucks at 250 yards with my AR15 and I didn't have to spray and pray, dump a 30 round magazine, and I didn't even have to resort to headshots. if it will do that to an animal that has evolved to inject itself with a huge dose of adrenaline at the first sign of trouble it will definitely stop a drug addled african teenager charging you with an AK47(sorry if I offended anyone but towel head remarks tend to get to me for some reason). anyone that says that the 5.56 is not powerful enough to perform their duties is a poor shot to begin with and the last thing he needs is a heavier round making him flinch.

lastly in normandy when paratroopers were dropped in every place but their intended targets all of those guys probably only had a hand full of 30-06 and 45 ACP ammo availible and many had to start stockpiling german arms and ammo because they rapidly ran out of ammo. I can fit over 100 rounds of 5.56 ammo in the same amount of space that I can fit about a couple dozen 30-06 rounds. if you are operating well ahead of the front lines or you are in an area where you cant get resupplied, which would you rather have 50 rounds of 7.62x51 or 100 rounds of 5.56x45?

I apologize if this post is too abrasive but that's just the cold hard truth spoken from a guy that has studied history enough to know that we moved away from big hunkin' rounds for a reason.

 

[d2wing]

Ok, I'll reword that, unless you have been in combat, your opinion about what is a good combat rifle or round doesn't mean much to me personally.

 

[suzukisam]

Ok, I'll reword that, unless you have been in combat, your opinion about what is a good combat rifle or round doesn't mean much to me personally.

.

 

[BrocLuno]

I think the best answer is to use the right tool for the job and there is no single answer to every situation. It is fairly well documented that the .556 could use some help beyond 500 yards for combat effectiveness. In this situation, everyone could likely agree a .308 would serve as a more effective combat weapon, or any of the other larger caliber choices.

However, for house to house, close in combat the 556 appears to be very effective, along with shotguns and other assorted varieties. When these sorts of discussions arise, I think it is very important to talk about the mission.

I agree whole heatedly. 99% of the time you are humpin, not shootin. When the shootin starts, it ain't range time. The 556 is entirely adequate for anything close-in out to 400m that contains high volumes of water like a torso. The round reacts violently on wet substances.

OK, it has limitation on wall and door penetration if the doors have been reinforced. But a lot of fighting has been done in locations that are not "urban". The average grunt needs to be able to carry. This is very very important. That's why they were looking at plastic shells and such. Eliminate the weight of the brass. The 556 is a good current compromise. Especially if you also have squad weapons to back you up.

Non-vets do have a place to comment. I'm OK with that. Please feel free to ask away. We'll try to explain what happens in the field. And, every mission around the world is not Iraq or Afghanistan. Germany, Bosnia, Korea, Africa, the list goes on. Think about a round that can work from sub-arctic to desert sand and be carried in reasonable volumes?

The 556 may be getting long in the tooth. It might be time to rethink it. But, jeez - that means us and all Nato countries and a bunch of allies in the Pacific. The ammo volumes are in the tens of millions of rounds. the replacement has to be clearly superior. Not maybe better. It needs to be head and shoulders above the current round and that's a tall order.

 

[d2wing]

Shadow, I do not need a second hand account. I live with my own.
I tend to get very worked up over armchair experts. Free to express opinion yes. Expect you imaginary scenario to mean anything to me, a decided no.

 

[Cosmoline]

Yeah, but they don't count for much when some guy who can't walk 1/2 a mile, let alone do a 30 mile forced march with a combat load, decides to pontificate out what type of gun/ammo/gear/etc.

I don't think it's necessary to go into combat or be a veteran to understand the gravitational issues. Just hike or bike ride to the range and anyone can find out the really big difference between an AR carbine and an M1A.

But I do think, with Hague out of the way, an upgrade to the ballistics in the 6.5mm range would be a major improvement without a major increase in ammo weight. If we're sticking to FMJ then there's no reason to bother at all. In fact with the greater stability and exterior ballistics of bullets in that diameter, they're less likely to break apart or tumble on impact.

 

[LJ-MosinFreak-Buck]

Some of the reasons why I think we haven't messed with anything (calibers), is because, like others said, it'd cost a lot of money and logistical headaches to change calibers of our combat rifle.

5.56x45mm NATO does the job fine, or would be even better had it been (like others stated) left in the 20" barrel with a slightly slower twist rate.

I do believe, however, that preventative maintenance, or just by maintenance terms in general, is important here. Why would our military want to change barrels out faster than they do now?

Just cheese doodles for thought.

 

[Hangingrock]

My war was a long time ago different climate and place. I witnessed the transition from the M14 to the M16. Being part of an AO/FO team our responsibilities were different than the grunts. I’ll allow that the 45ACP is not always a one shot show stopper, carbon upped was a phrase often heard related to the M16, and artillery outgoing /incoming is an attention getter.

As for todays wars it’s simply a different time and place. Drawing parallels between yesteryear and today is difficult at best except for death or severe injuries. On a personal level dealing with the aftermath most adjust with in reason others don’t but the memories linger.

 

[Sergei Mosin]

The 556 may be getting long in the tooth. It might be time to rethink it. But, jeez - that means us and all Nato countries and a bunch of allies in the Pacific. The ammo volumes are in the tens of millions of rounds. the replacement has to be clearly superior. Not maybe better. It needs to be head and shoulders above the current round and that's a tall order.

I am reminded of the introduction of the Garand. The Army technical people wanted to chamber the weapon in a new cartridge, the .276 Pedersen. Compared to the .30-06, the .276 Pedersen had lower recoil, was less powerful (but still powerful enough), and in .276 Pedersen, the rifle would have held two more rounds.

But the Army had vast stocks of .30-06 ammunition on hand. The new cartridge was good, but it wasn't that much better than the .30-06 - not enough better to justify a change. So the Army stuck with .30-06.