Weapon *Life Expectancy*

Oh, now we're just talking about MGs. Just tossing away the bolt action rifle bit, eh? My 20,000 round comment applied to the post about the original M1917. It fired more than 20k rounds and the barrel survived. No ifs, ands, or buts about it.

Note:
I have to find it but let's not forget the British Vickers. Remember the 12-hour barrage of ~1,000,000rds from 10 MGs? It averaged out to 10k-12k per barrel. I have the stats per MG somewhere under my stacks of piston-primed cases.

 

In the case of the BREN, the BAR & Japanese LMG's & HMG's... yes, possibly but most of the other MG's used in WWII were recoil operated & didn't use the propellant gas pressure to operate the action. The Vickers was recoil operated w/ a booster at the muzzle which did use gas to help keep things moving. The US M1917 & M1919 & the German MG34 & MG42 were all recoil operated.
Something everyone has to consider is that the greatest & most destructive source of heat is the burning propellant as it leaves the cartridge case. This is like a gas cutting torch eroding the chamber throat. A barrel that has seen a high round count from rapid fire will have a high throat erosion rating w/ a muzzle wear wear number that is still in the acceptable range. A US weapon (rifle or MG) inspected & found to have TE & MW beyond a certain range would be pulled for service & have a replacement barrel fit. This is how WWI era 1903's will be found w/ WWII era 2 groove barrels.

 

You are correct Schoolr, I was waiting for someone to catch that. However, semi-auto rifles and MGs have the benefit of immediately cycling the action between shots. That allows some air flow in to cool the barrel and vent propellant gases. Bolt actions aren't so lucky.

Hmm, sounds familiar...

 

What is my source for what? That MG's get hot quicker than bolt action rifles? I think you know this already...

Well I know that the M1919 used WD-4150 steel for its barrel, same as the M1 Garand.

I said nowhere that they were interchangeable. I said they were similar, and indeed they many times were in terms of materials used, esp. during WW1.

 

Yes, we've always been talking about MG's. My comments about 20,000 rounds fired applies to the M1917 water cooled machine gun, and always have.

 

Regarding steels used by the Germans (I don't know how they ever got involved in this), they used everything from high quality chrome molybedum alloy steel to nickel, vanadium, manganese and straight carbon steel. 1945 MG42 barrels were made of carbon steel.

 

I can't speak for the CWO2; but, I'd like to see your info for this reference, I have never heard of such a low number.

 

Read some of the original weapons manuals for rifles such as the M1903. Back in WW1 it only had a barrel life of approx. 1,000 rounds thanks to the high erosion caused by the powders used back then. Advances in powder chemistry technology increased barrel life to about 7 to 10 times this by WW2. And today we're hitting the 20k range for bolt actions thanks to advances in both powder chemistry and metallurgical technology.

 

Is this some kind of joke? Your source for MG barrels wearing out faster.

Ok, from your facts, was 4150 always used in either weapon?

How is having different contours similiar? The mass of each barrel was different. It sounds like you want to play "apples are similiar to oranges". Don't expect another reply from me unless you start bringing some facts to the table.

 

That's great! Considering I already mentioned it. Are you even attempting to have a real discussion?

 

I've looked through my 23-10 and 23-20 and couldn't find any reference to 1,000 rd ware out of the barrels for the 1903 Springfield. 7,000 rds is not a lot and I find it hard to believe that the rifle would have been adopted with that rate of wareout possible.

I will repeat; cite your source

 

Don't know how I missed this gem. By this you are illustrating the fallacy of your point, if not your facts, too. You seriously believe the M1917/9 could only fire 4 (four) 250rd belts and then the barrel needed replacing?? The 3-man BAR team of WW1 carried a minimum of 540rds and the 2-man team of WW2 carried 500+. These teams could only reload their mags once and then the BAR needed to be rebarreled? Seriously??

 

He's talking about the 1903 Springfield!!!!! Obviously someone has never spent a week at a live fire and maneuver range. It's a ridiculous premise with no basis in common sense. 1,000 rounds is nothing no matter what the weapon is and it's especially rediculous when you refer to automatic weapons and machine guns. If a machine gun barrel wares out after 1,000 rounds what's the sense in cleaning it?

 

Wahl, I bring to you a horrible fact that if you shoot a few thousand rounds through a very expensive magnum depending on how fast a round you choose and you happen to be using the wrong powder, you may soon offer your gun up for sale as it won't survive without rapid erosion at the start of the grooves.(It takes much less than 1000 rounds) Ever wonder why the pawn shops have a lot of used magnums around? If you shoot a thousand rounds through a barrel that may be no problem. If you shoot that many rounds without allowing sufficient cooling you may not reach 1000. Soldiers may remember shooting machine guns that took off on their own when hot and had to know to reach up and pull a round from the belt to stop their gun. I am going to change the subject mid-stream since you have mentioned one of my favorite guns the 1903 Springfield. If you include the 1903-A3 Springfield you are talking of a strange evolution of a firearm almost all of which would in my opinion be a success. I am going to say something that may classify me as old school! Modern gun smiths have a range of military weapons they give little respect to. They will warn you of blowing up chambers caused by (according to them) those early guns may have metallurgy problems or may have head spacing problems (which may be true) but there is little respect for them compared to the expensive modern hunting rifle that sells for $800 on up. I will draw your attention to the Krag which has certain attributes that soon brought it out of date. However I am going to point out a plus characteristics it had. It worked well with the round it was designed to shoot. It was made with a metal containing a matching amount of carbon in the steel to maintain a more natural and enabled form of lubrication for passing bullets if in war the shooter could not keep it constantly oiled. No one today credits the metallurgists with that trait in the steel. When the first of the 1903 Springfields were made they used a similar metal and the metal was adequate to the task of the shells made at that time. Now you can shoot standard power shells through those guns (if properly headspaced) and I have been doing that for years on mine. I do not load up extra power shells to use in it as many of today's hunters think they need to do all the time. The machining of the early 1903 Springfields was generally good to excellent. As they came to the end of the run of these they may have changed to metals having a higher strength in the metal. As time went by the 1903A-3 was manufactured by many different companies and some were rushed for war production and the machining may become quite rough but the guns were still considered great. If you like smooth bolts some of these will not please you. However the ability of these guns to take a bit more pressure is recognized by the gunsmiths. What I am trying to say is if we go back to what these guns were designed for we would find more positive things to say about each of them. Certainly the demands we make have increased through the years and improvement has been necessary. Putting the barrel from an early 1903 (carburized steel) on a machine gun would be a stupid thing to do if you understand metallurgy. The high carbon steel is not a good metal to get rid of heat and it would be predictable that this combination would not work. However if you had a bolt action that only shot intermittently this would be a long lasting gun with its more enabled lubrication with the high carbon barrel. I'll just bet they didn't talk to Browning when they tried to speed up production by using the 1903 barrel! If we compare guns and barrels we need to stick to their intended design and the powders available at the time of manufacture. I for one would like to have a Krag but I am happy to have my 1903 Springfield with early serial number and I will match the smooth bolt it has against so many very expensive guns that can only equal it with the smoothness and tightness of the bolt. Of course this depends on the military surplus gun you are able to select when purchasing. In guns it is important to compare apples with apples and oranges with oranges as was mentioned. And I am not saying our Krag faired well with lets say what it's soldier user had to face up with like a mauser. I have those too and respect them.

 

Yes, you mentioned heat. I wasn’t trying to be redundant.
I am getting the impression that some of the posters think that the heat is a result of the friction of the bullet travelling down the bore. I wanted to point out that the greatest & most destructive source of that heat is the burning propellant & it’s attending high temperature/high pressure gas.

 

If you burn a barrel out it's not the barrel's fault and it's not the ammunition's fault it's the shooter's fault. Anytime you exceed the design charecteristics of anything it'll break; that's why there is a 'cyclic rate' for every weapon.

The same thing can be said with your 'runaway gun' analogy. I have never seen it happen where it was not the direct result of poor operation or user maintenance and that's M-249's, M-60's and M-2's.

During the time I have spent in the military and in law enforcement I have put hundreds of thousands of rounds down range and that number increases exponentially if you want to include .22's. The caveat is that for every hour I spent on the range there was at least an hour spent on weapons maintenance afterward.

Bottom line is that 1,000rds of disciplined fire through a well maintained weapon will not ware out a barrel.

 

I am not at home at this time, so I've been relying mostly on memory, but it seems I remembered correctly:

http://www.exteriorballistics.com/reference/rifleinout.cfm
African Sporting Gazette

When I get home next month and have full access to all my books, I let you know where I've read it.

As for MG barrel life, personal experience is what counts the most here, and I know that during sustained fire most wont last past 500 rounds. I haven't fired many rounds through a water cooled machine gun before however, but I have a very hard time believing that one could last for 20,000 rounds of sustained fire, even with todays metals & powders, let alone with the highly erosive stuff they had back before and in WW1.

 

Easy, read every MG manual you have. Usual barrel life is between 500 to 3000 rounds, for calibers of .308 and up at least.

M2 HMG has an average barrel life of 3,000 rounds for one. The .308 cal M60 has barrel life of 250 to 500 rounds during sustained fire...

Try wearing out a rifle barrel before a MG barrel. Wont happen... unless your using single shot in your MG ofcourse.

I'm just quoting what the Springfield document is telling me.

The metals used were the same and barrel thicknesses were often quite similar as-well, take the barrel of the M1919A6 for example, it wasn't much thicker than that of the M1903.

 

I never said that the M1917 could only fire 1,000 rounds, I said that in WW1 the M1903 started out by having barrel life of only approx. 1,000 rounds because of the powder used, and it turns out I remembered correctly.

The water cooled M1917 would naturally have a longer barrel life than this thanks to the much better cooling provided by the water-jacket, but it wouldn't last to 20,000 rounds, by then it would've been a smoothbore.

 

What you're talking about is the .30-03 that was originally intended to replace to .30-40 Krag. '03 Springfields were orginally chambered in this round. When the weapon was in field tests (1st 1,000) they were prone to excessive barrel ware and throat erosion. The .30-03 was revamped into the .30-06 by trimming down the case length, changing the projectile weight and reformulating the powder, this round would go on to become the cal .30 M2 cartridge. The '03 Springfields that were already in production or were in field trials were rebarelled.

This was remedied by 1912 and none of these rifles saw service in WW1.

There was also in interwar period round wich produce 5,500 fps mv, for long range and machinegun use known as the cal .30 M1. this round was discontinued in the late '30's.

So, once again you have 'sorta-kinda' got it right; but, not really. I still haven't found your source for the 1,000 round reference.