The Marine Corp's Experimenting With New Service Rifle?
- Thread starter GOYABEAN
- Start date
Prudii
.357 mag
So what makes this thing special other than 50 more meters of effective range?
Its just a gas piston AR, specifically an H&K 416.
Marine Cpl
.577 Tyrannosaur.
It looks no better than your AR except for the full auto capability.
meketrefe
.450/400 Nitro Ex
H&K is a very good piston but overpriced.
The brits went to LMT and got a superior product than the US got with the knights.
They should be working in a new platform and 6mm round.
Otherwise is more of the same M4 related shortcomings.
The brits went to LMT and got a superior product than the US got with the knights.
They should be working in a new platform and 6mm round.
Otherwise is more of the same M4 related shortcomings.
I actually was able to fondle an H&K piston AR. The civilian version is what the MR223 or some such? I do not not see why itbis nearly twice what a SIG or LWRC would cost. And I I have seen pictorial proof that the H&K still has issuse with the lower and buffer tube getting torn up from carrier tilt. Never been a fan of piston ARs, the design is not set up for it. If were I were the Marines I'd be begging CZ to test the improved BREN 807/2
meketrefe
.450/400 Nitro Ex
Like you indicated the carrier tilt is very real but before it becomes an actual issue the guns go through preventive maintenance to replace barrels and other parts anyway. If one is going to get a piston, that is the piston to get or a clone of it that is more reasonable in price. I think in the short term provides a more reliable system in all sort of conditions, specially for special forces and amphibious operations. But in terms of general infantry and unless is geared to suppressing fire the DI has the potential to out perform all of them including the AK and given there is a regular maintenance cycle with proper cleaning and oil. The DI receiver will outlast all other systems. Now the question is how critical that is when a receiver and bolt are not that expensive. I guess it is a lot more complicated in the AK because when the bolt rails are gone are gone and that might mean replacing the entire receiver therefore the entire firearm. Now we are talking possibly in the 80K-100K rounds threshold and obviously this depending on how this has been serviced and maintained and the qualities we have to start with.
A decent piston for the money is the Adams piston that with a few minor tweaks to address some of the shortcomings becomes a very nice and reliable piston for civilian and police use. It comes standard with 3 easy adjustments for full open, suppressed and canceled.
The Marines will get something good in quality but like the US Army and other branches the tend to pay more for less.
ProgSpear
.338 Win Mag
meketrefe
.450/400 Nitro Ex
Possibly something like that slightly improved and with extra freebore. This will do everyhing the chinese service round 5.8x42 does and a bit more.
Or maybe use a slightly larger case in the 42-43mm range and will do even more with 85gr to 90gr battle ammo and up to 105gr long range bullets.
We could even take the 6.8spc case, streghthen that a little and neck it down to 6mm and make a bad ass infantry round. Or use the 6.8 SPCII that is
already pretty good.
The Chinese abandoned the 7.62x39 and 5.45 Russian cases and IMO made a move in the right direction with the right claiber, not too light, not too heavy. It is sad we cannot get this case here and also in strong brass. This would make a perfect AR and also a great donor for other cartridges. Thanks god we have the 6.8 and Hagar to play with.
5.8×42mm
I think pistons in ARs add weight, cost, complexity and recoil impulse all to fix a problem that is more perception than actuality. An AR can be kept running reliably in the field for thousands of rounds by doing no more than squirting lube in the action every thousand rounds or so. I do like the the short stroke piston gas sytem better, but in a rifle designed for it from the outset. What the market needs are high quality short stroke orignal designs for under 2k.
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meketrefe
.450/400 Nitro Ex
Pretty much everything has been invented already. We can repackage it in different styles, paint it in different colors but it would pretty much be the same.
I think the Tavor is a pretty good advancement. With a modern BP soldiers are able to keep a the 18 to 20" barrels yet less overall length. Less heat yet more speed and energy. What we need is a new infantry round. The 223 has come a long way but in the new battlefields we need something with 100 extra meters
of effective range and more momentum on the target. also more versatile for super short CQB and special unites rifles. The 6mm would be ideal.
If we trash the entire magazine system a 6x46 would make a very nice including a decent long range round for sniping soft targets or even machine
gun suppressing fire.
Existing AR15 receivers could be retrofitted to shoot a light bullet with existing magazines or a new larger magazine will fit
the magazine well for the same casing with the long range round.
This is what a modest 6x46 from a very similar magazine than the current one that will give at 2.45 COAL.
Effective range 700-800 yards.
At 300 yards has the same speed and energy as the 7.62x39 at the muzzle.
6x46 Infantry round.
Your Input Variables
Ballistic Coefficient 0.525 Velocity (ft/s) 2850 Weight (grains) 107
Maximum Range (yds) 1000 Interval (yds) 100 Drag Function G1
Sight Height (inches) 1.5 Shooting Angle (degrees) 0 Zero Range (yds) 100
Wind Speed (mph) 10 Wind Angle (degrees) 90 Altitude (ft) 0
Pressure (hg) 29.53 Temperature (F) 59 Humidity (%) 0.78
Ballistics Results
RANGE (YARDS) VELOCITY (FPS) ENERGY (FT.-LB.) TRAJECTORY (IN) COME UP IN MOA COME UP IN MILS WIND DRIFT (IN) WIND DRIFT IN MOA WIND DRIFT IN MILS
Muzzle 2850 1930 -1.5 0 0 0 0 0
100 2675 1700 0 0 0 0.6 0.6 0.2
200 2507 1493 -3.4 1.6 0.5 2.5 1.2 0.3
300 2345 1306 -12.3 3.9 1.1 5.8 1.8 0.5
400 2188 1138 -27.5 6.6 1.9 10.5 2.5 0.7
500 2038 987 -50.1 9.6 2.8 17 3.3 0.9
600 1894 853 -81 12.9 3.7 25.4 4 1.2
700 1757 734 -121.6 16.6 4.8 35.8 4.9 1.4
800 1628 630 -173.5 20.7 6 48.5 5.8 1.7
900 1507 539 -238.5 25.3 7.4 63.7 6.8 2
1000 1395 463 -318.9 30.5 8.9 81.6 7.8 2.3
Don't like bullpups either, not great when prone, where a solider will do much of his shooting, awkward mag changes, limited access to the action complicates identifying and clearing stoppages. And yeah it's all been done before.......but. SCAR is one of the best of the newer designs but is bulkier than need be and waaay to expensive. The improved version of the BREN 805, the 806 or BREN 2 depending on who you ask, looks like an excellent design but is not slated to be imported anytime soon if it even is and the 805 is at the absolute edge of what I would consider mainstream attainable. Aside from the various piston AR designs what other current manufactured short stroke designs are there? Well there is the SIG MCX, but it is kind of a weird hybrid design I'm a little wary of. I really like the BREN design though as essentially a modernized AR 18, just a few minor issues with it, lack of last round bolt hold, fussy, flimsy interchangeable magwells. Both of which are addressed in the update version.
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Marine Cpl
.577 Tyrannosaur.
@meketrefe , while you are correct that they should go with another caliber, they will not. There's too much invested in 5.56 to change everything. Then you have NATO.
I don't see it happening for many years. Decades even.
A different better designed round in heavier grain is as far as I think they'll go.
I don't see it happening for many years. Decades even.
A different better designed round in heavier grain is as far as I think they'll go.
I think those velocity levels should be dialed back, for full auto controlablity in rifles/carbines. I've fired AKs on full auto and they are only somewhat controlable. Free recoil of our 6mm cartridge should be kept under that of the 7.62×39. A light rifle/ heavy machinegun load scheme could be adopted provided either load is safe and functional across all weapons platforms. I favor something like 105 gr for the heavy load. But thats inspired by the Lee Navy cartridge which was a round nose design and a spitzer point of the same length would weigh less so I dunno..... maybe 90-95 gr?
meketrefe
.450/400 Nitro Ex
The recoil impulse will be less than the AK yet more speed and energy. Totally controllable in small bursts same as the 6.8 spc.
Same initial principal as the lee navy but modern ballistics would leave the navy in the dust.
Something like this...
2 on the Left 80-90 gr infantry round... shorter / Less recoil.
Right: 105gr long range round.
View attachment 3831
Same initial principal as the lee navy but modern ballistics would leave the navy in the dust.
Something like this...
2 on the Left 80-90 gr infantry round... shorter / Less recoil.
Right: 105gr long range round.
View attachment 3831
Doc8404
.450/400 Nitro Ex
They were issued to our FTs in 2011 when we were in Afg. Didn't seem special.
I think thats pretty much the concept right there. What case is that? There seems to be more taper than is necessary in a modern brass cartridge. Now if we went with a steel case...... Do you think this could competently fulfill everybrole from CQB carbine to 600 meter sniping to coax tank machinegun use? Thats what I envision, a return to the one caliber for all small arms, excluding specialty stuff such as 300 win mag for long range sniping and the usual gamut of .50 BMG stuff.
Oh and a few ideas regarding bullet construction: a pronounced rearward weight bias and a heavy cannelure to promoting yaw then fragmentation. Also such a long bullet gives us the opportunity for a proper combined effects cartidge with a hardend penetrator core sitting behind a light fragmenting section. We can have AP and soft target performance in one round. A dedicated AP round would have formidable armor pentetration as well.
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meketrefe
.450/400 Nitro Ex
I don't think three can be a substitite for the 308 winchester. ...well the 7mm 08 will do everythign the 308 does and a little more including
better long range for snipers and other purposes. the problem the 7mm 08 with 120gr to 165gr will be too much weight for the main battle rifle.
I mean, there are 308 rifles that are comparable in weight to a 5.56 but the issue is the weight of the ammunition thus reducing the amount of
firepower a soldier can carry. That is why anythin larger than a 6mm, 6.8 or some sort of 6.5 will not happen and the people doing long range
or gunners need a minimum of anti-material capabilities (quick car stoppers) and some decent momentum on the targets something that will be
hard for the 6.5mm and below. There is simply no way to send enough mass to the needed speeds to be effective at that.
That is why a unique intermediate battle roound will not happen. The 308 will stay that is a great round and the need for a slithgly better
round w/o being too much heavier will contine. The Chinese were smart. They saw the future and went 6mm. Now they have a better round that NATO and the russians. And still loaded mild due to the steel cases but they can pump it up if they want.
better long range for snipers and other purposes. the problem the 7mm 08 with 120gr to 165gr will be too much weight for the main battle rifle.
I mean, there are 308 rifles that are comparable in weight to a 5.56 but the issue is the weight of the ammunition thus reducing the amount of
firepower a soldier can carry. That is why anythin larger than a 6mm, 6.8 or some sort of 6.5 will not happen and the people doing long range
or gunners need a minimum of anti-material capabilities (quick car stoppers) and some decent momentum on the targets something that will be
hard for the 6.5mm and below. There is simply no way to send enough mass to the needed speeds to be effective at that.
That is why a unique intermediate battle roound will not happen. The 308 will stay that is a great round and the need for a slithgly better
round w/o being too much heavier will contine. The Chinese were smart. They saw the future and went 6mm. Now they have a better round that NATO and the russians. And still loaded mild due to the steel cases but they can pump it up if they want.
I disagree, the 6mm Lee Navy was selected for penetration of the superstructure of naval vessels and the 112 grn loading at 2500 fps accomplished that. A modern 105 gr 6mm load would do fine against cars or other unamored targets, for anything more there is the 50 BMG. Also wouldn't the trajectory of a heavy 6mm be flatter and retain velocity better than the 7.62x51? That would take care of range. The extra energy of the 7.62x51 is irrelevent, snipers have the 300 win mag now for long range sniping as as I said before the 50. BMG can handle whatever the 6mm can't. Switching calibers is only worthwhile if the new round replaces the 5.56 and 7.62 otherwise we should just stick with the 5.56.
meketrefe
.450/400 Nitro Ex
The lee was a huge advancement. We are talking same principal just with modern bullets and powders and smaller stronger cases suitable for modern firearms.
The 7.62x51 momentum is very important not just for a designated marksman but also a machine gunner. The 7mm would do all that better but if we go smaller in case and caliber there is not enough momentum for hard target and intermediate barrier. Momentum is not energy, two different things. Then when connecting you also want enough frontal section.
The 6mm could go as high as 120gr and the 6.5 160 grains but the problem is you are limiting efficiency of the case that results in speed loss and then sectional density is too much to get the best balance in terminal ballistics. So realistically the best of those calibers will be between 85 to 105 grains for the 6mm and 100 and 140gr for the 6.5mm.
That is where the 7mm with a range of 120gr to 170grains strikes a perfect balance between ballistics, grain, sectional density and frontal section but again we get into rounds that are too heavy for the main battle rifle.
In the end no matter how we look at this physics has a way to balance itself out.
Like always there is a trade-off of some sort.
These are the parameters we have to consider when we look at efficiency from all angles:
- Caliber and Grain/weight.
- Speed.
- Ballistic Coefficients.
- Sectional Density.
- Frontal Section.
- Terminal design and impact thresholds.
Then for the General Purpose ( very important to military) we have to consider too:
- Shape and design
- Pressure and thrust
- Overall length
- Weight of the entire round
These are perhaps some of the most important aspects in the last 60 years that has an impact in everything else.
The 7.62x51 momentum is very important not just for a designated marksman but also a machine gunner. The 7mm would do all that better but if we go smaller in case and caliber there is not enough momentum for hard target and intermediate barrier. Momentum is not energy, two different things. Then when connecting you also want enough frontal section.
The 6mm could go as high as 120gr and the 6.5 160 grains but the problem is you are limiting efficiency of the case that results in speed loss and then sectional density is too much to get the best balance in terminal ballistics. So realistically the best of those calibers will be between 85 to 105 grains for the 6mm and 100 and 140gr for the 6.5mm.
That is where the 7mm with a range of 120gr to 170grains strikes a perfect balance between ballistics, grain, sectional density and frontal section but again we get into rounds that are too heavy for the main battle rifle.
In the end no matter how we look at this physics has a way to balance itself out.
Like always there is a trade-off of some sort.
These are the parameters we have to consider when we look at efficiency from all angles:
- Caliber and Grain/weight.
- Speed.
- Ballistic Coefficients.
- Sectional Density.
- Frontal Section.
- Terminal design and impact thresholds.
Then for the General Purpose ( very important to military) we have to consider too:
- Shape and design
- Pressure and thrust
- Overall length
- Weight of the entire round
These are perhaps some of the most important aspects in the last 60 years that has an impact in everything else.
The 6mm Lee worked well enough in the Marine's potato digger machine guns, even if the gun itself was not the best. I think a 105gr 6mm would perform well enough to replace the 7.62×51. But perhaps moving up to 6.5mm would provided greater flexibility and less compromise?
meketrefe
.450/400 Nitro Ex
@Podmonkey
Why don't we start a thread to discuss the perfect service rounds in our view?
Every forum has one of two of this type of threads and I think we could have some interesting genuine insight.
It nothing else it helps folks see other aspects of ballistics and what they are good for.
I think the 6mm would be perfect for a smaller case while the 6.5 will require something larger perhaps
not very different from the 308 itself in size and that is where a simple 7mm/08 will beat them both.
Basically because the 6.5 is maxed out at 140 -145 grains and the 7mm/08 is ballistically superior with 160-170 grains.
I still like the 6.5 (I have a few of them) but now I see it as a limited caliber.
so what about a new thread. I think this subject already came up when we discussed potential threads.
anything but politics!
Why don't we start a thread to discuss the perfect service rounds in our view?
Every forum has one of two of this type of threads and I think we could have some interesting genuine insight.
It nothing else it helps folks see other aspects of ballistics and what they are good for.
I think the 6mm would be perfect for a smaller case while the 6.5 will require something larger perhaps
not very different from the 308 itself in size and that is where a simple 7mm/08 will beat them both.
Basically because the 6.5 is maxed out at 140 -145 grains and the 7mm/08 is ballistically superior with 160-170 grains.
I still like the 6.5 (I have a few of them) but now I see it as a limited caliber.
so what about a new thread. I think this subject already came up when we discussed potential threads.
anything but politics!
Well go ahead and start one and I'm there, but uts seems like everytime anything technical is discussed it dies right away.
Prudii
.357 mag
So its a full auto, piston operated AR with a slightly longer barrel? Why are our tax dollars going towards this again?
Yes, and I don't know.
Marine Cpl
.577 Tyrannosaur.
In my opinion, they should go to the 70 gr TSX. The hell with the Hague Convention that we never signed into.
It expands to .50 caliber. It works better on auto glass. It doesn't fragment into pieces when it hits mud bricks. it's velocity threshold for expansion is much lower than the velocity needed for fragmentation in other rounds dependant on fragmentation for effectiveness. And best of all, they don't have to change anything in regards to magazines, barrels, bolts, ECT....
It expands to .50 caliber. It works better on auto glass. It doesn't fragment into pieces when it hits mud bricks. it's velocity threshold for expansion is much lower than the velocity needed for fragmentation in other rounds dependant on fragmentation for effectiveness. And best of all, they don't have to change anything in regards to magazines, barrels, bolts, ECT....
meketrefe
.450/400 Nitro Ex
@Willjr75
The M855A1 and MK318 work on the same principal. The MK318 has a bit of lead but solid base so effectively produces
similar effect with great penetration and a lot shorter so it can be launched faster than a 70gr solid that steals a lot of powder.
The TSX 70gr they are quite long and have a large bearing surface so that is why they keep them to 62gr.
IMO with the 223 small case the barnes 62gr TTSX gives a tad more with less.
Also a some 60gr-75gr bonded is kept shorter yet they should perform very well as they are stout in structure.
I think the sirocco 75gr is a very nice stout bullet for penetration but they are so expensive to practice.
But the MK318 performance is hard to beat a most popular ranges.
The M855A1 and MK318 work on the same principal. The MK318 has a bit of lead but solid base so effectively produces
similar effect with great penetration and a lot shorter so it can be launched faster than a 70gr solid that steals a lot of powder.
The TSX 70gr they are quite long and have a large bearing surface so that is why they keep them to 62gr.
IMO with the 223 small case the barnes 62gr TTSX gives a tad more with less.
Also a some 60gr-75gr bonded is kept shorter yet they should perform very well as they are stout in structure.
I think the sirocco 75gr is a very nice stout bullet for penetration but they are so expensive to practice.
But the MK318 performance is hard to beat a most popular ranges.
Marine Cpl
.577 Tyrannosaur.
@meketrefe, why 62 gr in TSX? Word on the virtual street is that the 70 gr penetrates deeper than the lighter and faster 62 gr. What benefit is gained from the extra 150 fps? I got those numbers from Black Hills. 2850 vs 3000.
And isn't a solid copper bullet that doesn't break apart and stays solid much better for mud and clay barriers that our military encounters? The MK318 will fragment in those barriers.
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Staying with 62gr might just be logistical, twist rates stay the same, BDCs stay the same ect. I think the Marines have a great all purpose load in the MK318, too bad the stubborn ol Army wants to go with the M855A1. And that's coming from an Army guy.