I need a little help settleing an agument I got into at work the other day. A co-worker of mine has several AKs, and HKs and was talking about how much he enjoys shooting them all in rapid fire, as in firing all the rounds in the clip as fast as he can pull the trigger.

As respectfully as I could, I cautioned him against constantly fireing his semi-auto rifles as fast as possable, especially if doing so causes the barrel to become to hot to touch with his bear hand, because doing so will dramaticly lesson the life of his barrels and cause them to suffer a dramatic reduction in accuracy, in other words, "shoot out your barrel".

He asked me to explain this to him as he had never heard of it. I replied that although I do not own any semi-auto rifles, I know one of the worst things I can do to my bolt action rifles is to shoot (especially in hot weather) so meny rounds out of them until the barrel gets to hot to touch. I stresed that this did not apply if done rarely, but only if you do so at every range outing.

He replied to me I was compleatly wrong and that the barrels of his AKs and HKs were made out of and I quote here "military grade steel" that unlike barrel steel used in non-military rifles is made to withstand 1000s of rapid fire rounds before accuracy suffers.

I answered that basicly barrel steel used in military rifles like AKs, HKs, M-16s and the like is to my limited knowledge no different than the steel used in my bolt, or lever rifles. The only difference I am awere of is some military rifle barrels get a chome lining.

I am basing my opinion on articles I have read of military weapons such as older Browning .30cal machine guns of WW-II type as well as newer .30cal M-60s that stated if I recall that you would basicly "shoot out" or drasticly degrade a machine guns barrel if shot on prolonged sessions of full-auto fire.

So whats the scoop here on the steel used for military type semi and fully auto barrels? are they realy made out of a different alloy then say SST or chrom-molly?

Not much difference. Let him wear out his barrel, he will find out by himself. If he is able of shooting his rifle accurately, that is.

I agree with the above. There were some barrels - the FN or "Browning" GPMG that were "stellite" lined but if he shoots too much he will heat the barrel and it will wear.

70% of the energy (or "heat") of a cartridge is wasted as "heat to barrel" anyway. So firing quick at a fast rate will heat up his barrel and it will wear once it gets beyond a certain temperature.

That is why machine guns always had spare barrels! To change them when they became hot so as to take them off the gun before they reached the point where the damage would begin to be done.

However this is quite a high temperature approaching that of being, literally, "red hot". Not just simply "too hot to handle".

Only the collet zone of the chamber had a stellite insert to keep the headspace correct despite prolonged firing without possibility to change barrels.
it did not diminish the wear and tear on the barrel but allowed to keep the weapon firing. It was developed for the Flying Fortress .50 HMG.

Remember the outside of the barrel is not an accurate indicator of how hot it is inside the barrel!

For the barrel to get too hot to touch, how hot is it 3/8" away? Especially say, after 10 shots are fired in a matter of seconds. It takes a while for the heat to migrate to the outside of the barrel, but meanwhile it was confined to the first few thousandths of the throat.

However, a lot of these discussions are just a "pearls before swine" conversation, where they think you're wearing a tinfoil hat until they come moaning their gun doesn't shoot well anymore. I'll toss out a neutral comment about throat temperatures and see if they are interested in that avenue, if they are then maybe it can be talked about in detail otherwise it is best to hold ones tongue in many situations. Just my opinion. <G>

Edmond,

Can you give a comparison to the wear of a water cooled machine gun barrel over an air cooled one?
How about those old water cooled machine guns like that were used in no man's land in WWI, and elsewhere. They certainly got a work out there.

Joe

The only caveat that I would offer here would be most of the AK's and the SKS's I am familiar with have chromed bores which would help. Also most of the 7.62X39 ammo is low intensity, say some 45,000 psi per SAAMI specs whilst the 7.62X51 NATO is loaded to 62,000 psi and the old 30-06 is 50000 CUP - so it is not quite the same vis a vis. As I once heard an old timer speaking of the 220 Swift: "firing that thing is like turning a cutting torch into the chamber!" I do not have pressure specs at hand for the Swift but IIRC it was 65,000 psi.

Those water cooled MG could shoot a few thousand rounds in a row until the water was brought to steaming temperature. With air cooled MG, you should have to change barrels after the second ammo box, 400 to 500 rounds or the barrel would be shot out around 800 to 900 rounds.
I have seldom seen a MG 42 barrel that was not shot out on those I could examine that had served during WW2.

I remember reading an account written by a german machine gunner on the eastern front when they switched from MG 34 to MG 42. He wrote that usually they started to open fire when soviet assault waves were at a 600 m distance and switched barrels until the waves were around 300 m. If the assault had not been broken , they did not have time to change barrels anymore, they could see tracers going through a few ranks of soldiers and the barrels going to cherry red temperature.
Then, they used grenades, look at pictures, you often see grenades ready near the MG.
Usually, it ended in hand to hand combat with spades after the magazines of light weapons, MP and pistols, were emptied.

http://fr.youtube.com/watch?v=HkxGPSxrrD8&feature=related

The MG 51, 74 and 83 are swiss versions of the MG 42

http://fr.youtube.com/watch?v=H_gPUfWd__U&feature=related (look at the barrel change)

http://fr.youtube.com/watch?v=BRMesd1PSKg&feature=related (lotsa BS inb comments, nice video, italian speaking swiss soldiers)

The modern MG 3 ( MG 42) used by many countries.
The best MG ever made in my opinion.
http://fr.youtube.com/watch?v=TAxkvctd5Ps&feature=related

http://fr.youtube.com/watch?v=fwr8GGFBGyw&feature=related

http://fr.youtube.com/watch?v=-uYNFilb-YA

http://fr.youtube.com/watch?v=ebJOT95Gh3k&feature=related

http://fr.youtube.com/watch?v=hSKSsjpkZ3c&feature=related

http://fr.youtube.com/watch?v=j8imJ42K8ug&feature=related

http://fr.youtube.com/watch?v=4IEim1pyYM8&feature=related

Just tell the co-worker he might be right and try not to engage in logical conversation with him in the future. It's just not worth it.

quote:

Originally posted by Edmond:
Those water cooled MG could shoot a few thousand rounds in a row until the water was brought to steaming temperature. With air cooled MG, you should have to change barrels after the second ammo box, 400 to 500 rounds or the barrel would be shot out around 800 to 900 rounds.
I have seldom seen a MG 42 barrel that was not shot out on those I could examine that had served during WW2.

I remember reading an account written by a german machine gunner on the eastern front when they switched from MG 34 to MG 42. He wrote that usually they started to open fire when soviet assault waves were at a 600 m distance and switched barrels until the waves were around 300 m. If the assault had not been broken , they did not have time to change barrels anymore, they could see tracers going through a few ranks of soldiers and the barrels going to cherry red temperature.
Then, they used grenades, look at pictures, you often see grenades ready near the MG.
Usually, it ended in hand to hand combat with spades after the magazines of light weapons, MP and pistols, were emptied.

http://fr.youtube.com/watch?v=HkxGPSxrrD8&feature=related

The MG 51, 74 and 83 are swiss versions of the MG 42

http://fr.youtube.com/watch?v=H_gPUfWd__U&feature=related (look at the barrel change)

http://fr.youtube.com/watch?v=BRMesd1PSKg&feature=related (lotsa BS inb comments, nice video, italian speaking swiss soldiers)

The modern MG 3 ( MG 42) used by many countries.
The best MG ever made in my opinion.
http://fr.youtube.com/watch?v=TAxkvctd5Ps&feature=related

http://fr.youtube.com/watch?v=fwr8GGFBGyw&feature=related

http://fr.youtube.com/watch?v=-uYNFilb-YA

http://fr.youtube.com/watch?v=ebJOT95Gh3k&feature=related

http://fr.youtube.com/watch?v=hSKSsjpkZ3c&feature=related

http://fr.youtube.com/watch?v=j8imJ42K8ug&feature=related

http://fr.youtube.com/watch?v=4IEim1pyYM8&feature=related

"The modern MG 3 ( MG 42) used by many countries.
The best MG ever made in my opinion."Edmond,
You say the best MG ever made in your opinion. Other than being cheaper to manufature, why would you say the MG42 compares to the MG34? I never knew but one person that had used both and that's another story but he perferred the MG34 to the MG42, stated repeatedly that the select fire feature alone made the MG34 a better weapon. What say you?

The select fire trigger feature had been discontinued in 1940 and the rate of fire increased hence suppressing the "advantages" of the MG 34.
The barrel was difficult to change, had to turn the receiver to unmask the rear of the barrel and raise up the front of the weapon to get the barrel out of the barrel jacket.
It was so well overengineered that once very dirty and overheated it was no more reliable if you had to add dirt and mud, even worse.
The only reason it was not discontinued was because a round shape MG barrel jacket was needed to be used as on board weapon on MBT, armoured vehicles and planes. A square section like the MG 42 could not be used with firing ports and keeping said ports sealed.

The MG 42 is accurate and much more reliable, 5 rounds bursts are really efficient as a LMG between 300 and 500 meters. German troops used them mainly as HMG on Lafette 34 tripod, it is a really stable platform.

He died a few years back, but a good friend of my best friend was an officer in the Korean War (he retired as a Col). He always claimed that directly or indirectly he killed hundreds of thousands of men. He was later given a military commendation because his requests and recommedations directly lead to the electric powered gatling guns used in Puff, etc. He wanted guns that wouldn't seize up under continual use and actually requested to break out the old Gatling guns the army still had in storage. Request was denied because of ammo availability.

Back to the topic at hand, he often told the story to his confidants of how they would kill the Chinese by the tens of thousands. They would emplace 8 to 12 Browning machine guns ( I think from memory they used mostly .30s because of the ammo wt) on a ridge, start firing at the human wave attacks at about 800 to 1000 yards, fire until they got to about 300, grab the guns if they weren't melted, bug out over the ridge to waiting jeeps and trucks and call in the pre-positioned artillery. He said almost no one in the front few thousand men ever survived this kill zone. They would pile up the remains with a dozer if they went back. They did this day after day. He also used elevated indirect fire with machine guns to kill and harass the enemy at a couple of thosand yards over a hill. Interesting fellow and a helluva shot in person as well.

quote:

Originally posted by Gatogordo:
He died a few years back, but a good friend of my best friend was an officer in the Korean War (he retired as a Col). He always claimed that directly or indirectly he killed hundreds of thousands of men. He was later given a military commendation because his requests and recommedations directly lead to the electric powered gatling guns used in Puff, etc. He wanted guns that wouldn't seize up under continual use and actually requested to break out the old Gatling guns the army still had in storage. Request was denied because of ammo availability.

Back to the topic at hand, he often told the story to his confidants of how they would kill the Chinese by the tens of thousands. They would emplace 8 to 12 Browning machine guns ( I think from memory they used mostly .30s because of the ammo wt) on a ridge, start firing at the human wave attacks at about 800 to 1000 yards, fire until they got to about 300, grab the guns if they weren't melted, bug out over the ridge to waiting jeeps and trucks and call in the pre-positioned artillery. He said almost no one in the front few thousand men ever survived this kill zone. They would pile up the remains with a dozer if they went back. They did this day after day. He also used elevated indirect fire with machine guns to kill and harass the enemy at a couple of thosand yards over a hill. Interesting fellow and a helluva shot in person as well.

Saw a docudrama on the History Channel recently [R. Lee ?] that showed some of these 'human wave' attacks in Korea - had a gunner with a .30 Browning firing non-stop. The loader was lying beside the gun, raking empties away with both hands.
Also, I have my heard my brother talk about using AA quad fifties to break up and repulse these attacks. Hard to imagine anyone or anything being able to withstand the big fifty, much less four of them firing at once!

quote:

Originally posted by TrapperP:
...had a gunner with a .30 Browning firing non-stop. The loader was lying beside the gun, raking empties away with both hands.

Early fifties version of shock and awe?