Over heated barrel?

Am enjoying and learning from the comments here by guys with some expertise. I do a lot of target practice as well as praire dog shooting with my Rem 700 in .223 with factory sporter barrel. Nice thing about .223 is that it runs very cool. Can run 15-20 rounds in 15 to 20 minutes before any change in POI. In my rifle the POI climbs about 1.5 to 2 inches at 100 yds but then stays stable at that point. I shoot my .243 sporter barrel with 58 gr VMax at 3850 fps which makes it ballistically similar to a 22-250 for varmint hunting, however it heats up and starts spraying very quickly so I only shoot it while I give my .223 a cool down when shooting sand dogs.
The point of this is that apparently the load being used and the type barrel, ie sport vs heavy varmint or target barrel with have a significant effect on the barrel heating issue and can vary widely.
 
FWIW, I regularly shoot my bolt rifles so the barrel is pretty hot (too hot to grab near muzzle/can) and POI does not shift. Has something to do with rifle/barrel quality.
 
When you weld something, or cut it with a torch, the surface gets super hot - enough to melt the metal - but just a few mm below the surface it's still solid; thus there is a gradient of temperature. This logic applied to the throat would suggest the surface of the throat gets hotter than the retained temperature of the barrel in the throat area, given a gas temperature of over 3000 F.
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Depends on what type of metal. Stainless, maybe (depending on how thick of a piece of metal you're welding).

99% of the time, welding heats up the whole shi-bang (inside, outside, top, bottom, left, right).
The biggest factor is exposure time, weld penetration and ammount of amps.

But in the case of rifle powder, we're looking at an extremely short period of time that the throat of the barrel is exposed to that temperature.

Source: Studied 2 years in Welding/Industrial Technology and worked as a Heavy Equipment Welder for the oil field for 3 years.
GMAW, TIG, SMAW Certified Welder. Worked with Aluminum, Stainless Steel, Iron, Carbon Steel, Titanium and Copper.
 
99% of the time, welding heats up the whole shi-bang (inside, outside, top, bottom, left, right).
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"Heats up" is an imprecise term. Sure, it all gets hot. But only the part that the torch or arc touches melts.
 
Back many years ago . . .
A new line solider that had been in country (Vietnam) a very small time and was manning an M-60 after his gunner was hit. There were three of us in a small cover area and he was shooting like mad. I had yelled to him to space out his fire and not just keep shooting. When the fight was over, the front sight on the 60 was over at about a 45° angle. Yes, he had heated the barrel way too much
Bottom line, don't get the barrel too hot
 
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So you're saying that 3300 F flame temperature won't ever heat the surface of the throat more than 1100 F. I don't believe that. If that were true then you could never the the bulk of the barrel over 1100F due to how heat transfer works (ie, delta t), and I've measured MG barrels over that temp myself.
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No no no no. The "flash" is so fast and intense that it erodes the metal. It would take many of those flashes to heat the throat to 1100 F. It would be similar to a spectrograph (metal chemistry tester) where you have a 50,000 V. spark hit the metal sample in a vacuum. It instantly erodes (vaporizes) the metal but you can pick that sample up immediately with your hands and it's not hot.

The main thing that gets the barrel hot is the "friction" of the bullet going down the barrel. Obviously with some types of automatic weapons you can get the barrels super hot from this friction... to where they melt! An example is given above on the front site tipping at a 45. That couldn't happen if the heat was mainly being generated by the powder flash.

I'm just saying that with a bolt gun you won't get the barrel hot to hurt it.

But if you feel this is wrong so be it. I made a living as a engineering metallurgist for a transmission company and that's all I'll say.
 
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Corroborated by Lilja

http://www.riflebarrels.com/faq_lilja_rifle_barrels.htm
The big enemy to barrel life is heat. A barrel looses most of its accuracy due to erosion of the throat area of the barrel. Although wear on the crown from cleaning can cause problems too. The throat erosion is accelerated by he at. Any fast varmint type cartridge can burn out a barrel in just a few hundred rounds if those rounds are shot one after another without letting the barrel cool between groups.
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In the 1870's, it is reported that Tom Nixon once shot 120 buffalo from a single stand without moving his cross sticks, but that he ruined the barrel of his Sharps in the process.
 
Q.) What causes throat erosion?
A.) Throat erosion is caused by the blow torch effect of powder gasses and solids striking the throat. Large amounts of unburned and burning powder travel down the barrel at the bullet's speed and at the gas pressure. These particles act as a sanding compound against the throat. The throat also gets the heat first, and for a longer period of time each shot. These factors (gas speed and pressure, particulate speed, and intense heat) cause throat erosion.

I found this in a technical article. I'll go with this. And also that the whole barrel gets hot from the heat caused by the friction of the bullet going down it. I think a hot barrel and throat erosion are two seperate topics.

And I stand "somewhat" corrected.... :rolleyes:

In the case of most target rifles and many varmint rifles, a large number of shots may be fired over a short time span. As the barrel heats up from continued firing, so does its susceptibility to erosion and fouling. While this can be controlled when varmint hunting, rapid fire and long strings of sustained fire are part of the game for the competitive high-power shooter. Since the shooter can’t control this, he needs to recognize it as a potential problem and deal with it accordingly. Cleanings will need to be both more frequent, and thorough, to prevent fouling from getting a foothold. With the increased cleanings, proper cleaning technique becomes essential to avoid damage caused by the cleaning itself. Even with proper cleaning technique, many target shooters go through a new barrel every season.
 
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Barrel heat

If you want to try this trick again, first send your rifle to this place
www.teludynetech.com

You will be absolutely amazed at what this product will do for your rifle in both the heat (or lack thereof) and accuracy improvement catagories.

TTI has been heatedly discussed on the Firing Line so I am not trying to start another argument. Go the site, read what they say and try it for yourself. They have a bunch of highly satisfied customers, Lanny and Tracy Barnes to name a couple. I peronally have shot dozens of their rifles and know they work as they promise.



"When seconds count it's encouraging to know the police are only minutes away!"
 
quoting Warbirdlover "I've seen that before. That would work. Don't like the looks though."


I own an early 70s model Kleingunther. It has a slender sporter barrel but it was highly accurate. I myself didn't like the bull barrel look at first, but it does grow on you after a while.

As they say "looks is in the eye of the beholder".

Cheers!
 
If you want to try this trick again, first send your rifle to this place
www.teludynetech.com

You will be absolutely amazed at what this product will do for your rifle in both the heat (or lack thereof) and accuracy improvement catagories.

TTI has been heatedly discussed on the Firing Line so I am not trying to start another argument. Go the site, read what they say and try it for yourself. They have a bunch of highly satisfied customers, Lanny and Tracy Barnes to name a couple. I peronally have shot dozens of their rifles and know they work as they promise.
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I was at an event last year where the Teludyne Straight Jacket was "explained" and demoed. I heard some extraordinary claims. We put a SJ'd AR-15 upper on our M16 lower (with permission) and shot approx 3 or 4 mags full-auto in 4-6 minutes (ie, as fast as I could load the magazine from loose rounds again). After 3-4 mags, just using human senses, it seemed as hot as any other F/A AR-15 upper/barrel after the same number of mags (ie, very hot). After the last mag, I set it down and smoke/steam started to billow out of the "SJ" barrel. So in summary, I was not real impressed after being told that it basically did heat "magic" and made everything run cool.
 
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