Military round comparisons

[stanc]

I suspect that folks are confusing barrel lengths when comparing velocities. Some folks use 24" for testing. Others shorter barrels.

So, a manufacturer reports data for a 16" barrel, the reader thinks it is a 24" and subtracts the usual 150-20 ft/sec and says "Holy Cow, those velocities a really low!" The problem is they tend to not go back and cross check sources, so they think they are arguing from fact when they using erroneous information to slander a cartridge.

Hornady shows velocities for both 24" and 16" barrels, with a difference of 230 ft/sec. No confusion there.

[stanc]

Of course, if a long barrel is needed to extract the performance you want without going to a bigger and more powerful cartridge, then there's an obvious answer...work on a decent* bullpup design, and enjoy a 20 inch barrel in a gun the same overall length as an AR-15 with a 10-12 inch barrel.

*fully ambidextrous without having to dismantle and rebuild the gun, and with an adjustable stock length.

Trouble is, such a "decent" bullpup is, at this point in time, no more than a theoretical possibility. Unless and until somebody makes it proven reality, it isn't worth discussing.

Which means we're limited to whatever performance can be extracted from the 14-16" barrel of a conventionally-configured carbine.

[LRRPF52]

Hornady shows velocities for both 24" and 16" barrels, with a difference of 230 ft/sec. No confusion there.

Hornady shows velocities for 14.5" and 18" barrels, in the 8th & 9th reloading editions, respectively. I haven't seen any 24" data from them yet.

[JASmith]

Hornady shows velocities for both 24" and 16" barrels, with a difference of 230 ft/sec. No confusion there.

...unless one looks a little deeper. The Hornady handloading manual lists the same velocity for a 14.5" barrel as they show for their factory load in a 16" barrel. Hence there is reason to suspect even this otherwise very reliable source and yet another source of confusion.

[stanc]

Hornady shows velocities for 14.5" and 18" barrels, in the 8th & 9th reloading editions, respectively. I haven't seen any 24" data from them yet.

See factory load data from their website:

http://www.hornady.com/store/6.5-Grendel-123-gr-A-MAX/

[LRRPF52]

That 16" velocity is actually 14.5" velocity, with an AA 14.5" gun that has a pinned muzzle device for legal length. Thanks for reminding me about their published 24" data. It's sad day for me that it took you to jog my memory...got any space for me in the room next door? Any hot nurses, or are they all ex-cons with steroid use problems and kleptomania?

[stanc]

That 16" velocity is actually 14.5" velocity, with an AA 14.5" gun that has a pinned muzzle device for legal length. Thanks for reminding me about their published 24" data. It's sad day for me that it took you to jog my memory...got any space for me in the room next door?

Yeah, there is a vacancy. I'll tell the facility manager to expect your call.

Any hot nurses, or are they all ex-cons with steroid use problems and kleptomania?

Surprisingly, two of the (LVN) nurses really are hot, and the third isn't at all bad. However, they usually don't come around unless a resident has a medical issue that requires attention.

The caregivers who do all of the daily work are quite pleasant and well behaved -- no theft problems here -- but none qualify for the "hot" category. Some are cute, but all are rather plump...

[Nukes]

Not much really. You'd have to tweek the geometry of the tray, topcover components, and bolt.

My arguments with Stan aside (:p), the links should be the biggest obstacle, simply because setting up high volume sheet metal stamping is no task to be taken lightly. You have to be pretty dedicated on that one.

The fact that Ares is so astronomically challenged in just delivering 5.56 guns though is the real world killer. If he can't deliver on 5.56 in any reasonable manner, then Grendel is pretty much out of the question.

It's a shame really IMO. Geoffrey wanted military sales, but I doubt he'll ever see them. If he could actually manufacture like a pro (ala Colt), instead of just making really nifty prototypes that rarely see the market, then he'd be insanely rich by now.

I'd add a bit of mass to the sytem for a trials gun, but a 6.5 Grendel Shrike in about the 10 pound range would be a peach. If I could be General Curtis Lemay reincanated, I'd have my AF Security Forces abduct Bill Alexander and Geoffrey Herring and lock them in a bunker together. I wouldn't let them out until I had the Grendel Shrike. Then I'd pay them a kabillion dollars for the rights, and contract Colt to make it. Done, problem solved. Tada! I'd standardize the round, and then declare I didn't want to here any crap whining until plasma rifles in the 40 watt range are available.LOL

Ha, ha, ha... just make sure they buy high-end e-commece software and that the bunker is not on a military reservation, so they can hire more staff :-)

My Browning 1885 falling block conversion is sounding less expensive by the minute.

[LRRPF52]

The thing I have come to realize is that the 6.5 Grendel is the cartridge I and many others have been looking for as a great all-round chambering that will fit in an intermediate cartridge weapon system of lighter weight. It has very little recoil, and lots of energy retained at distance, coming out of a little AR15. I enjoy shooting it more and more each time I go out with it, especially as factory ammunition has become so much more available.

It's real value is made evident when you put it in the hands of an un-trained shooter, who hasn't shot past 100yds before, and they make 1st-round hits at 500m with it, with the impact dead-center of the silhouette, like my BIL did, after cleaning all my steel poppers and silhouettes at 300m and 400m, as if it was some silly video game.

[BjornF16]

I think the curve starts to take a dip between 16" and 14.5", but not so much between 14.5" and 12.5". Just like a 16" and 18" are hard to distinguish from each other, just like a 20" and 24" are indistinguishable when looking at velocities. 14.5" velocities for a 123gr AMAX are 2350fps, while they are 2450fps from a 16". The best velocity Hornady lists with the 123gr AMAX is 2500fps from an 18". The average loss I have seen with identical loads between a 24" and 16" was 18fps.

My suspicion is that this is a factor of gas system length, more than just barrel length. You'll notice that the guns that use rifle-length gas systems produce the same velocities (20", 22", and 24"), just like the mid-lengths (18" & 16"), and carbine lengths (14.5" & 12.5"). If true, the argument can be made that the shortest barrel length practical with the gas system used is most efficient.

What about a mid-length 14.5" like the AA Ultra-light?

I'm still awaiting parts or I'd be able to answer.

[Nukes]

Apparently I was very fortunate how quickly my Krieger barrel arrived. I'll quit whining about my magazines. :-)

[Tony Williams]

Trouble is, such a "decent" bullpup is, at this point in time, no more than a theoretical possibility.

Fusion power is a theoretical possibility. A decent bullpup could be made today, using existing technology.

Unless and until somebody makes it proven reality, it isn't worth discussing.

If it isn't discussed, no-one will realise that there is a need it could meet, and therefore no-one will make it.

The main problem with discussions about bullpups is that the detractors solely focus on specific problems with existing designs, rather than looking at what is easily possible now.

[stanc]

If it isn't discussed, no-one will realise that there is a need it could meet, and therefore no-one will make it.

It has been discussed ad nauseum, but still no one has made such a critter. If your idealized bullpup were feasible, why hasn't it been made yet?

The perceived drawbacks of the bullpup layout have been known for decades. It seems to me that if it is as simple to correct them as you say, somebody would've done so by now.

[stanc]

The thing I have come to realize is that the 6.5 Grendel is the cartridge I and many others have been looking for as a great all-round chambering that will fit in an intermediate cartridge weapon system of lighter weight. It has very little recoil, and lots of energy retained at distance, coming out of a little AR15.

Unfortunately, there is negligible info available on terminal effects with ball ammo, whether conventional FMJ or more recent types like M855A1. Without adequate hard data, I don't see how anyone can claim 6.5 Grendel is "good enough" to replace 7.62 NATO, or if a more capable round (6.5 GPC, 7 UIAC, etc) is necessary.

[Tony Williams]

It has been discussed ad nauseum, but still no one has made such a critter. If your idealized bullpup were feasible, why hasn't it been made yet?

The perceived drawbacks of the bullpup layout have been known for decades. It seems to me that if it is as simple to correct them as you say, somebody would've done so by now.

The problem is that most of the big purchasers of small arms (especially the USA) have a strong cultural preference for the traditional layout. Apparently mainly because it's traditional. As it costs a lot of money to develop a new gun, the big arms manufacturers focus on providing what the users say they want. Which means that there are few bullpups for armies to choose from.

The recent users and developers of bullpups (notably Israel and China) obviously don't care about instant ambidexterity or a variable-length stock (nobody except the US Army seems to regard the latter as a priority). So if the users haven't asked for these features, they won't get them.

FN made a valiant effort to address ambidexterity with the F2000 and came up with a new solution to it, but then spoiled their chances by having completely different controls and handling, as well as dedicated accessories rather than universal ones.

By a "decent bullpup", I meant one which addresses virtually all of the objections that supporters of the traditional layout can come up with. But if you don't need instant ambidexterity and a variable length stock, the Tavor X95 is fine (apart from its calibre).

If a general-purpose cartridge is ever adopted, then it is likely to generate more interest in a general-purpose rifle to fire it - compact enough for urban warfare but with good long-range ballistics for open-country fighting. Another new factor emerging is the growth in the use of suppressors (the US Army apparently wants these fitted to just about everything) which add significantly to the overall length of a rifle. These two factors both play to the bullpup's strengths. So it's worth pointing out the advantages of bullpups whenever the subject arises, to keep those involved in mind of their potential for solving various problems.

[cory]

The problem with issuing troops a weapon specifically for urban combat is that eventually they have to step outside the building and shoot at someone 100+ yards away.

My suggestion would be to focus on getting the troops the Grendel in an AR for shots at 10+ yards and a good pistol & round for CQB purposes.

[LRRPF52]

Traditional pistol cartridges are mostly inadequate for military operations. They are a last-ditch defensive tool for very close-in scenarios, and they suck at even that.

The one pistol cartridge that breaks this mold is the 7.62x25, which is awesome from a pistol or SMG.

[cory]

Traditional pistol cartridges are mostly inadequate for military operations. They are a last-ditch defensive tool for very close-in scenarios, and they suck at even that.

The one pistol cartridge that breaks this mold is the 7.62x25, which is awesome from a pistol or SMG.

Agreed! That's why I said develop a round. Okay well I meant to say develop. Haha

[stanc]

The problem is that most of the big purchasers of small arms (especially the USA) have a strong cultural preference for the traditional layout. Apparently mainly because it's traditional.

I'm sure that tradition is a factor. Armies in general -- and the US Army in particular -- tend to be conservative.

However, another very important factor is that, until recently, the available bullpups had significant drawbacks.

The recent users and developers of bullpups (notably Israel and China) obviously don't care about instant ambidexterity or a variable-length stock (nobody except the US Army seems to regard the latter as a priority). So if the users haven't asked for these features, they won't get them.

Quite true.

By a "decent bullpup", I meant one which addresses virtually all of the objections that supporters of the traditional layout can come up with.

Yes, I understood that.

But if you don't need instant ambidexterity and a variable length stock, the Tavor X95 is fine...

But, if the US Army requires those features, then the X95 is not so fine.

If a general-purpose cartridge is ever adopted, then it is likely to generate more interest in a general-purpose rifle to fire it - compact enough for urban warfare but with good long-range ballistics for open-country fighting. Another new factor emerging is the growth in the use of suppressors (the US Army apparently wants these fitted to just about everything) which add significantly to the overall length of a rifle. These two factors both play to the bullpup's strengths. So it's worth pointing out the advantages of bullpups whenever the subject arises, to keep those involved in mind of their potential for solving various problems.

I would agree (personally, I have long liked the bullpup concept), except that it has not been demonstrated that your "decent bullpup" can actually be made. Which means you are pushing a theoretical concept that may not be achievable in practice, as a preferred "solution" to the traditional design.

If I'm a little annoying on this, it's because I have grown weary of all the theoretical proposals that have been advanced with little or no hard data to support them.

[Tony Williams]

I would agree (personally, I have long liked the bullpup concept), except that it has not been demonstrated that your "decent bullpup" can actually be made. Which means you are pushing a theoretical concept that may not be achievable in practice, as a preferred "solution" to the traditional design.

If I'm a little annoying on this, it's because I have grown weary of all the theoretical proposals that have been advanced with little or no hard data to support them.

Well, bullpups which match the M4's controls are in service. A bullpup which is fully ambidextrous is in service, and so are a couple of others which can be used left-handed if need be, plus the ARX-160 which has switchable-side ejection. The only aspect which has not been demonstrated in a service weapon is a variable-length stock (although the new version of the Austeyr which has been adopted for service, the EF-88, has a shortened stock to allow for body armour).

To allow space for a variable length stock requires a shorter action than usual, but those are hardly new - the Russians demonstrated in the early 1960s with the Korobov TKB-022 (pictured earlier in this thread) just how short an action can be, leaving loads of space for an adjustable stock. Nothing quite as drastic as that would be needed.

So I think that to claim that these features "may not be achievable in practice" really isn't justified; most of the elements are in service in different guns, and nothing radically new would be required to achieve a variable-length stock.