Section Infantry Weapons

[Ron5]

Sorry dude, just trying to be helpful.

[mr.fred]

OK, I have no idea what ACC is saying. None whatsoever.

[marktigger]

but 7.62x51 NATO is an intermediate round! It's designed to perform like the full load .30'06

[mr.fred]

but 7.62x51 NATO is an intermediate round! It's designed to perform like the full load .30'06

If I remember my Hatcher correctly, the 7.62 NATO is loaded to match a reduced load 30.06. The reduced 30.06 being developed for rifles and similar shoulder arms as the full-power round developed for machine guns had too stout a recoil for such light weapons

[marktigger]

but 7.62x51 NATO is an intermediate round! It's designed to perform like the full load .30'06

If I remember my Hatcher correctly, the 7.62 NATO is loaded to match a reduced load 30.06. The reduced 30.06 being developed for rifles and similar shoulder arms as the full-power round developed for machine guns had too stout a recoil for such light weapons

from what i've read it was designed to use reduced loads of more modern and efficient propellents to match .30'06 performance

[ArmChairCivvy]

Some similarities here to a historical context: The French invented the smokeless powder just in time for the Boer War (but both sides had it, with its advantages).

Getting closer to what is a "full -power" round...Many of the Boer Mausers were chambered for the 7mm Mauser, a/k/a 7x57mm. This is a different round than the more famous 8mm Mauser, used extensively later by the Germans in both World Wars.
- the Boer sharp shooters ran circles around the opponents using smaller rounds

Magazine development was also a differentiator in the overall performance: The Mauser was a magazine fed, bolt operated rifle that used striper clips to reload the magazine, whereas the Lee Enfield used in the Boer War did not use stripper clips, and cartridges had to be loaded individually. This was perceived as a disadvantage compared to the Mauser, and charger loading, using stripper clips, was introduced in 1904 with the SMLE.
- the roll-out had gone far enough by 1907 for the older models to be retrofitted with the better (copied) mag design
- small things are easy to overlook, but the test of reality normally brings them (after the fact) quickly into service

The new posts- button somehow skipped mf. fred's comment (that he has no idea what I am talking about; which I have now seen). My msg was very simple, as the full-power rounds (save for special uses. like the Lapua Magnum) are no longer the flavour of the day:
- for a compromise, the shorter 7.62s are better than the (nowadays full length) 51
- the German "Kurz" had to be toned down in power, to make it workable (we all know who did that, giving "us" the original)
- ACC says that the above reworked into today's AAC round (as linked, by now far above) is a better compromise than the original (or those competing ones that are in service, even if different from 7.62). Then there is the holy grail to find a new "intermediate" round for use on all occasions ...

[marktigger]

Some similarities here to a historical context: The French invented the smokeless powder just in time for the Boer War (but both sides had it, with its advantages).

Getting closer to what is a "full -power" round...Many of the Boer Mausers were chambered for the 7mm Mauser, a/k/a 7x57mm. This is a different round than the more famous 8mm Mauser, used extensively later by the Germans in both World Wars.
- the Boer sharp shooters ran circles around the opponents using smaller rounds

Magazine development was also a differentiator in the overall performance: The Mauser was a magazine fed, bolt operated rifle that used striper clips to reload the magazine, whereas the Lee Enfield used in the Boer War did not use stripper clips, and cartridges had to be loaded individually. This was perceived as a disadvantage compared to the Mauser, and charger loading, using stripper clips, was introduced in 1904 with the SMLE.
- the roll-out had gone far enough by 1907 for the older models to be retrofitted with the better (copied) mag design
- small things are easy to overlook, but the test of reality normally brings them (after the fact) quickly into service

The new posts- button somehow skipped mf. fred's comment (that he has no idea what I am talking about; which I have now seen). My msg was very simple, as the full-power rounds (save for special uses. like the Lapua Magnum) are no longer the flavour of the day:
- for a compromise, the shorter 7.62s are better than the (nowadays full length) 51
- the German "Kurz" had to be toned down in power, to make it workable (we all know who did that, giving "us" the original)
- ACC says that the above reworked into today's AAC round (as linked, by now far above) is a better compromise than the original (or those competing ones that are in service, even if different from 7.62). Then there is the holy grail to find a new "intermediate" round for use on all occasions ...

look at the British attempts to produce a 7mm .276-.280 round post boer war and the myths around the Mauser rifles many of the Boers were using martini action rifles it was their standard of Marksmanship that was the game changer. If all had gone to plan the SMLE would have been replace by the Pattern 13 rifle from enfield but difficulties with the new .276 cartridge meant when WW1 broke out the Commonwealth had the SMLE the P13 became the P14 in .303 and the M1917 in .30'06 the main battle rifle of the American army in WW1





yes Mae is very cute

[ArmChairCivvy]

The reduced 30.06 being developed for rifles and similar shoulder arms as the full-power round developed for machine guns had too stout a recoil for such light weapons

So it is all of an accident really? RE
" difficulties with the new .276 cartridge meant when WW1 broke out the Commonwealth had the SMLE the P13 became the P14 in .303 and the M1917 in .30'06 the main battle rifle of the American army"

[marktigger]

withe the SMLE yeap it was more luck that it made it to WW1 as main battle rifle. The reports make interesting reading Ian Skennerton's book the American Enfield is very good. Over heating with the trial cartridges was a huge issue.

[ArmChairCivvy]

Next accident: After Pearl Harbour McArthur decided to fight with what was in the stock piles (gearing up for war had only just begun, and again a golden opportunity to change -despite preparations being made - was missed because of "all the suddenness".

[marktigger]

the plan was to replace the SMLE with the P13 though by August 1914 that process would have been still happening and I suspect we would have reverted to the SMLE anyway given we were issuing 1895 Lee Enfields to some units and some still had Martini Henry Enfields. We had to go to the Americans for additional rifles and were also buying Canadian Ross's to

The US was caught out more by springfield's inability to supply the quantities needed in 1917 as the US army rapidally expanded and the "Spare" capacity in the Remington winchester and eddystone factories that had just finished the British contracts meant they were geared up to mass produce rifles and the M1917 was a modified P14

[ArmChairCivvy]

The US was caught out more by springfield's inability to supply the quantities needed in 1917 as the US army rapidally expanded and the "Spare" capacity in the Remington winchester and eddystone factories that had just finished the British contracts meant they were geared up to mass produce rifles and the M1917 was a modified P14

Interesting, explains a lot.

However, after the war there thorough tests towards changing the rounds (and thus the rifles/ carbines) and the standing army was so small that it would have been easy (=cheap) to achieve. When the shooting started, the question that came to the fore was "how many million have we got" and after the answer: "Right, let's get plenty more!"

[marktigger]

after ww1 there wasn't allot of money or will to spend money on defence and as you say there was millions of rifles in store....even the SMLE was looked at to be updated to the mk IV? (there wasn't even the money to do that) and the No4 only came much later. Same with the Americans large numbers of 2nd line troops in WW2 had M1917 rifles as well as those they exported and lend leased to the Home guard.

[mr.fred]

The new posts- button somehow skipped mf. fred's comment (that he has no idea what I am talking about; which I have now seen). My msg was very simple, as the full-power rounds (save for special uses. like the Lapua Magnum) are no longer the flavour of the day:
- for a compromise, the shorter 7.62s are better than the (nowadays full length) 51
- the German "Kurz" had to be toned down in power, to make it workable (we all know who did that, giving "us" the original)
- ACC says that the above reworked into today's AAC round (as linked, by now far above) is a better compromise than the original (or those competing ones that are in service, even if different from 7.62). Then there is the holy grail to find a new "intermediate" round for use on all occasions ...

If you are going to go smaller than 7.62mm NATO, why keep the calibre? A lighter bullet at lower velocity with the same cross sectional area will have a much more curved trajectory and it will be harder for a soldier to score a hit.
How are the short 7.62mm rounds "better" than the NATO standard?
The .300 Blackout is supposedly similar to the 7.62x39mm M43 cartridge, which lags far behind the 7.62 NATO round in terms of power and effective range.

[Timmymagic]

after ww1 there wasn't allot of money or will to spend money on defence and as you say there was millions of rifles in store....even the SMLE was looked at to be updated to the mk IV? (there wasn't even the money to do that) and the No4 only came much later. Same with the Americans large numbers of 2nd line troops in WW2 had M1917 rifles as well as those they exported and lend leased to the Home guard.

And in many respects the M1917, whilst heavier, was better than the Springfield. It's got a faster action (still a Mauser action, but the bolt handle is better placed) and it's sights were way better than the Springfield.

Still it's round down range that counts, especially with conscript armies, and in that measure the SMLE was massively superior, and not that much less accurate.

[Timmymagic]

If you are going to go smaller than 7.62mm NATO, why keep the calibre? A lighter bullet at lower velocity with the same cross sectional area will have a much more curved trajectory and it will be harder for a soldier to score a hit.
How are the short 7.62mm rounds "better" than the NATO standard?
The .300 Blackout is supposedly similar to the 7.62x39mm M43 cartridge, which lags far behind the 7.62 NATO round in terms of power and effective range.

Why re-invent the wheel. The thinking around .280 British is still as valid as the day it was written down. Pretty much the same performance as 7.62 to 800-1000 metres and significantly lighter and shorter.

[ArmChairCivvy]

significantly lighter and shorter

Good things to have (in real life); if you can add different grain weights - depending on what you expect to be shooting at - the merrier.

About the 300 AAC Blackout (300BLK), specifically: " This system was developed to launch 30 caliber projectiles from the AR platform without a reduction in magazine capacity and compatible with the standard bolt.

Full power 115-125 grain ammunition matches the ballistics of the 7.62x39mm AK, and eclipses 5.56mm with much higher-mass projectiles for a more dramatic effect on the target."

[marktigger]

for a simple reason .280 "British" would never be accepted by the Americans if it ain't invented in the good old US of A forget it!

[marktigger]

significantly lighter and shorter

Good things to have (in real life); if you can add different grain weights - depending on what you expect to be shooting at - the merrier.

About the 300 AAC Blackout (300BLK), specifically: " This system was developed to launch 30 caliber projectiles from the AR platform without a reduction in magazine capacity and compatible with the standard bolt.

Full power 115-125 grain ammunition matches the ballistics of the 7.62x39mm AK, and eclipses 5.56mm with much higher-mass projectiles for a more dramatic effect on the target."

what sorts of ranges 200-300M? like 5.56 and SA80 or looking at ranges out to 600-800m something that 7.62x51 and the SLR could easily do

[ArmChairCivvy]

In this world nothing comes free... says he, swaps to the longer 7.62 round and exits under intense covering fire:

[ArmChairCivvy]

Full power 115-125 grain ammunition matches the ballistics of the 7.62x39mm AK, and eclipses 5.56mm with much higher-mass projectiles for a more dramatic effect on the target."

Gastonclocker linked today to an interesting article on the US forces thread that would indicate that I was not the only one worried about the std 5.56 lacking in punch:

" Although it's not an armor-piercing round, the EPR can penetrate 3/8 inch-thick mild steel at distances approaching 400 meters (based on the range at which 50 percent of the rounds can pass through the barrier). The M855 only penetrates this material out to approximately 160 meters.

[...]

Additionally, the EPR can penetrate concrete masonry units at ranges out to 80 meters with the M16 and 40 meters with the M4. The M855 can't penetrate this type of battlefield barrier at any range. "

They (of course) did a better job than my little thought exercise: did not compromise the range. But that did take a couple of decades (to get from M855 to the new round, EPR).

[Little J]

The Firearmsblog have just posted an article about our new "enhanced" 556 and 762 bullets...

http://www.thefirearmblog.com/blog/2016 ... mmunition/

[marktigger]

its how efficiently it dumps its energy into the target that is the clincher if it punches through retaining allot of its energy and keeping going its not effective. If it penetrates and in process is dumping a catastrophic amount of energy into the structures of the target its successful. Rounds that can punch through armour to great depths tend to be retaining they energy on impact

[ArmChairCivvy]

I will just copy the relative grain weights from the firearmsblog, as they were playing a part in the earlier discussion:

"The new 5.56mm round, which will be known as the L31A1 in British service, retains a bullet weight of 62 grains (4g), meaning its ballistic performance will be very similar – an important similarity for soldiers firing it down their SA80 rifles.

…

For the 7.62mm round, known as the L59A1 in British service, the biggest change is to the weight of the bullet, from 144 grains (9.3g) to 155gr (10g). "

[marktigger]

will out ammo become more nato compliant?