Barrel temperature ?
- Thread starter Baddog 0302
- Start date
Firing 5 shots and then sweating whether or not your gonna ruin the barrel with a 6th shot is stupid. Do you use the brake pedal in your car? Prolly not, don't wanna prematurely wear those pads out
5-10 shots no big deal. A hour straight of firing is a big deal. Don’t get petty, we’re not talking 5-10 shots. We’re talking 20-30 shots then loading up your mags and going again for 20-30 shots in less than a hour. You’re not giving enough time for the throat to release any heat so it just gets hotter and hotter. Touching the barrel to see how hot it is isn’t telling you anything. The first three inches inside the throat and forward is where the heat is.
No no no thats not what you said earlier. You said guys ruin barrels with 30 straight rounds of fire. I've been saying all along I do 20 or 30 round strings then I let the rifle sit for 5 or 10 mins and now your saying exactly that and calling me petty. It's like I'm arguing with a child
You’re a little slow aren’t kid. Did you read the entire thread or just nit picking?
I said I shoot five and let it cool, take several rifles to the range to fill in while the barrel burners are cooling down.
Sustained fire will kill a barrel, it’s been proven over and over, no one said 6 shots would. You’re pulling shit out of context to win a worthless argument.
If it's so fucking worthless of an argument why are you hell bent on proving him wrong?
You're a special kind of retard ain'tcha?
You guys are hell bent on proving me wrong. I’m the one that said heat kills barrels. Prove me wrong buttpirate
No one gives a shit what you believe. We're all just laughing at you and your golf bag full of rifles.
That’s what I expect out of you buttpirate.
You can’t prove wrong, so you lash out looking for your divas to join you. Why don’t you message them and get them to come over here and defend your honor.
Listen I hate 308pirate as much as the next guy, I've argued with him also before, but in this case he is correct and the comment about a golf bag full of rifles was funny. Your prolly one of those guys with a temp gun with him at the range
No, I’m just the guy with 4-5 rifles enjoying shooting without cooking my throats. No temp gun, although I do have one.
But with 4-5 rifles you don’t need a temp gun.The heating probably comes from both the increase in pressure and the powder burning. What that split is I dunno.
My thinking is that the pressure increases at a faster rate than the rate required by bullet moving down the barrel to maintain the same temperature. Then there's also the flame from the powder burning adding heat. Kind of pendantic I guess.
I dunno my degree isn't in physics nor have I ever designed muntion packages so *shrug*.
My contribution to this absolutely typical SH thread is that, if I correctly remember my chemistry 101 from 60 years ago, you guys have been talking about the Ideal Gas Law and not Boyle's as the Ideal combines Boyle's and Charles and so addresses both temp and pressure.
And with that I'm getting the hell out of this little tête-à-tête
Toodles....oh, and I actually do like @308pirate. We are both asshole curmudgeons...my kind of people....and we seem to be well represented here on the Hide. LOL
I mean, really....don't you agree that people who actually like other people are, well....lacking in discernment? ;-) hahaha
Carry on, gentlemen.
And with that I'm getting the hell out of this little tête-à-tête
Toodles....oh, and I actually do like @308pirate. We are both asshole curmudgeons...my kind of people....and we seem to be well represented here on the Hide. LOL
I mean, really....don't you agree that people who actually like other people are, well....lacking in discernment? ;-) hahaha
Carry on, gentlemen.
How the system is defined really doesn't matter. The volume is definitely expanding until the bullet leaves at which point pressure is released. My question is, what is the temperature of the chamber or the bore in front of the chamber at its hottest point? At what temperature does steel begin to erode?
6BR is overbore? I was under the impression it was the slowest of the 6mm offerings?
“Overbore” is the relationship between case volume and bore area.
So, anytime a cartridge has a decent amount of volume (think anything with a .308 body or similar) and is necked down to a smaller bullet, it will have a higher overbore calculation.
The question would be where do you draw the line and say something is overbore enough to matter.
Typically that line is around 8. 6br has ~ 8.3 ratio.
So it can be argued either way as it’s that close.
Generally speaking, when comparing the same caliber, you can predict that a higher overbore ratio will have less barrel life. Say a 6br compared to a 6cm.
However, you can *not* compare overbore very well across calibers. As it’s possible for the overbore ratio to be higher or lower from caliber to caliber and it won’t follow the same for barrel life.
Last edited:
Point being……
You can’t compare overbore between a .308 and a 6br. Doesn’t work like that.
But you can compare a 6br and a 6cm or a .308 and .300.
So yes, a 6br isn’t “overbore” in the 6mm category as it’s one of the lower ratios in the 6mm category.
This is why it’s so important to understand the “why” and “how” behind things.
Otherwise, people will say “.308 gets so much better barrel life because a 6br is overbore.”
Well, the .308 has an over bore of ~7.6 and a 6br is ~8.3. That’s really not a big difference. And that’s not why a .308 will go 5-8k rounds and a 6br is 3-3500.
Reason being this doesn’t work is because it doesn’t translate to pressure or temperature.
You can’t compare overbore between a .308 and a 6br. Doesn’t work like that.
But you can compare a 6br and a 6cm or a .308 and .300.
So yes, a 6br isn’t “overbore” in the 6mm category as it’s one of the lower ratios in the 6mm category.
This is why it’s so important to understand the “why” and “how” behind things.
Otherwise, people will say “.308 gets so much better barrel life because a 6br is overbore.”
Well, the .308 has an over bore of ~7.6 and a 6br is ~8.3. That’s really not a big difference. And that’s not why a .308 will go 5-8k rounds and a 6br is 3-3500.
Reason being this doesn’t work is because it doesn’t translate to pressure or temperature.
Not much, clearly.
Combustion creates some heat as it is an exothermic reaction and it creates a great deal of gas. The gas generation increases pressure which increases the total heat in the system. You see, as you add gas at a rate which exceeds the rate of growth of the containment vessel you add pressure.
No, not some. Virtually all of it.
How many joules of thermal energy come from compressive heating since you seem to be pretty knowledgeable about thermodynamics?
Shoot it hot or let it cool..... The gentleman asked a question, and a whole lot of people just give an opinion on what they do, seem to be more focused on what others are doing and getting butt hurt about it.
For the record, if I can avoid it getting "shit that's hot, I do", if others don't give a fuck because it's a "consumable", bully to you, effects no one else.
I think the saying is barrels are like tyres, true...... enjoy your burnouts
Cheers
Pete
For the record, if I can avoid it getting "shit that's hot, I do", if others don't give a fuck because it's a "consumable", bully to you, effects no one else.
I think the saying is barrels are like tyres, true...... enjoy your burnouts
Cheers
Pete
Sounds like your were observing some long range precision shooters, for which EVERYTHING plays in to the accuracy of the shot! Try a half-dollar group at 500 yards, a paper plate or smaller sized group at 1000 yards, most of us will need every conceivable advantage. These are the guys that question 1 grain more of powder, or two grains less, as they seek shooter's nirvana. I'm one of them, but nowhere near the above accuracies - yet.
WHAT is your shooting intention? Get a deer? Protect yourself from Zombies? Plinking (just shooting for fun, at most anything)? You won't really need long range high precision shooting for these endeavors.
So all you guys worrying about barrel heat do you stop on the road and check the temp of your tires too? I can guarandamntee you heat kills rubber faster than metal and you have to buy 4 vs 1.
Only when the tire pressure is really low and I’m not sure if it’ll make it to the next place that has air, and I didn’t have a spare for that trailer.
Mainly because you’re exactly right and heat kills tires fast. Sometimes my dirt bike will throw knobs off the back tire like a machine gun because it gets pretty hit doing 90 on the highway at 5 psi. 
Also, to the OP’s question- yea burnouts do shorten the life of your tires and they can be a lot of fun. Especially when you do them deliberately. Besides, it’s my tire and I’ll make it cry if I want to.
Open ‘er up and live a little. There’s a lot more fun out there to be had. Following the rules and being cautious all the time is proven to make you old.
Lol true!
I get my thrills in the woods. I cut trees and mud run a 540 John Deere skidder all day. Every day there’s something trying to kill me out there. Adrenaline galore! Lol
In Infantry training in the late 60's and early 70's we would run our M-16's in full automatic long enough to light a cigarette on the barrel. On the hill in Vietnam, I saw the results of similar shooting. Shooting tracers is very educating. (in lots of ways. Ever see an aircraft flying low over an active range? If I am at the controls, I am going to give any ranges a wide berth, ricochets are amazing events)
Back to the subject at hand. I have a temperature strip. When in a match, its time to put the equipment to its max, I shoot. When practicing, I use two rifles and switch off, paying attention to the temp strip. If the barrel becomes hot to the touch, I giver it plenty of time to cool. Yes I realize its a consumable. Our GMC is a consumable, but with a replacement cost of 50K, I don't intentionally abuse it just because I could replace it. Same with barrels. When the temperature gets excessive, I back off. For me, being retired, money does not grow on trees, and I don't own an orchard.
And, I don't go with max loads. I find what shoots good and go with it. Adjusting the trajectory?? that's what those little knobs on top of the scope are for
Back to the subject at hand. I have a temperature strip. When in a match, its time to put the equipment to its max, I shoot. When practicing, I use two rifles and switch off, paying attention to the temp strip. If the barrel becomes hot to the touch, I giver it plenty of time to cool. Yes I realize its a consumable. Our GMC is a consumable, but with a replacement cost of 50K, I don't intentionally abuse it just because I could replace it. Same with barrels. When the temperature gets excessive, I back off. For me, being retired, money does not grow on trees, and I don't own an orchard.
And, I don't go with max loads. I find what shoots good and go with it. Adjusting the trajectory?? that's what those little knobs on top of the scope are for
As noted multiple times: is the barrel performing to your standards.
Powder charge/temperature - big difference between a 6mm and a .416 or .460.
Friction.
Vibration- and under rated part of the puzzle. Vibration = heat.
Surface area to mass.
Finish
Coatings
Processing.
Post processing of the materials.
Post processing of the barrel.
Materials of course- types, purity, source material.
Active cooling.
Non- uniform heat in the bore of the barrel. Gradients.
Heat changes; nodes- both frequency and position and amplitude. It will also allow other frequencies to migrate and even combine under certain conditions. In short - the metal object is no longer able to function or be predictable.
Heat changes bore diameters- migrating ES and SD.
Heat changes the shape of the barrel- physical shape, length, diameters.
Some of these are small "doesn't matter" perhaps while others are elephants. However, in the chase for velocity and continuing precision all start to matter.
A man size target at 600m or 6" target at 1200m are not comparable. We were with a couple of SF groups this past year during a "trueing" exercise. In one case guns of unknown age and condition. The other brand new essentially. A value of 15-1600m was being established for trueing distances. However, by shots 7-10, the shooters had to stop as the guns were no longer predictable in order to create a true value for entry into a ballistics program. They were chasing unknown corrections. During that time we were shooting a 300Norma (the direct equivalent to the guns being used) and a 33xc which is considerably hotter. That day was in the 70's low 80's and our Norma was shooting superior groups at round 15-20 than most of the guns did in rounds 1-7. The 33xc was shooting better at round 15 in the same manner- shooting a 285gr Hornady at 3250fps. The other gun AR 260Rem... takes 30-40rds to really start heating up.
The Norma shoots a 230Berger at 2950 to 3000 (depending on powder) and has north of 1500rds thru it.
The 33xc well north of 800rds.
The 260 baskets of brass again north of 1500 rds.
By borescope the guns look to be well under a 500rd mark. The 260 - you have to really look for fire cracking.
Can you burn a barrel down- yes. Normal shooting.. we don't typically let our barrels cool until we are in the 20-50rd mark. Our chambers are the coolest part of the barrel.
Our barrels both reduce amplitude of the barrel and directs the waves. They are also radiators.
Reducing amplitude will not only make a more forgiving barrel but will reduce heat.
Reducing amplitude is also potentially free velocity. Changing directions no matter how small decreases velocity.
The cooling- if we can keep the base metal below transition points then it won't degrade due to fatigue. Think about a square block and a torch. What glows first - the corners. The rifling is a sort of of corner. We don't want it to pass into a transition point - in 416SS as low a 500deg.
Balance- things want to be "ambient" - heat migrates to the smallest spring board it can find- your lands.
A "throw away" commodity is understood. The term "hummer barrel". How many bench guys would tell you they would pay dearly to keep the few hummer barrels they have had like forever. A point of view. At what point of a commodity is acceptable to miss the 1500m shot because the barrel is done? Again a point of view. Our view is the barrel is a critical component. For those guys who race- do you run an aluminum rod in and endurance motor? Point of view. Not an argument. In the end does it meet your standards? That's all that matters.
Excellent and we'll thought out post. I'm sure you will be shit on immediately. What I got from that was, do what is acceptable to you. If you can love with the wear that's fine, if you can't take some precautionary steps mitigate barrel wear
Na, water cannot be compressed there for water in the bore will create wear and excess pressure. No thanks bro
Your 6.5 is done at 1800? Barrel life on a dasher maybe. Everyone I know is pushing their 6.5 CMs to 3-5k even with the PRS-style fast shot strings. Are they losing a lot of velocity or opening up at 1800?
Don’t be scared to share all that data you collectedI've been using an IR thermometer on my rifles a bit lately, mostly because there's one in the vehicle I take to the range. I started doing it with one particular rifle because it was walking the POI when it heated up, and I was curious if I could find the point at which is started.
The most recent time was because I was having trouble focusing on the target. Since I'm having vision issues as of late, and it's been a long time since I had to deal with heat mirage, I assumed it was my eyes. When the "Duh" light bulb went off over my head, I got the thermometer to see at what temps the mirage was starting to be an issue. Also started comparing heating of extruded powders vs ball powder. I also found where the barrel heated the most interesting, I assumed it would be closer to the throat, but it was in fact about mid barrel. Never stop learning, even if it that's the only purpose it serves.
My old Jeep will need a new engine in the future, it's just a fact. So why change the oil or use coolant.
not as drastic
some very well known competitors and smiths have been pushing a wet patch (alcohol, water, mix or both) though a hot bore
then 1-2 dry ones for decades
drops the temp considerably faster
ill keep names out of it, because we all know what will happen next around here
...but go read some older precision shooting magazines and articles
It started shooting really shitty and I couldn’t get it to come back in with new everything so I scrapped it
Jesus Christ, all the bitching and moaning is like listening to a bunch of teenage broads on the rag, whining about who got fucked on prom night......
If you care about your barrel don't let it get hot. (Too hot to touch is too hot to shoot). If you don't, then burn it up. You'll never convince one to do the other.
I don't like getting shotgun barrels hot, (shooting a fast round of Trap doubles on a hot day), only because you'll get a ton of plastic fouling in the barrels that's a bitch to clean out. (Using wire brushes on cordless drills, along with all the other bullshit). I hate cleaning guns as it is.
For AR-15 platform rifles, this Caldwell unit that fits into the magazine well works very well, and it has a rechargeable Lithium Ion battery. It will cool down a hot AR barrel fast. Like while you're reloading your magazines.
But as was mentioned, on a really hot day you're not going to be able to get it cooled down regardless of what you do. Unless you use some type of refrigerant or CO2. And that gets expensive.
www.midwayusa.com
www.lifelinereproductions.com
If you care about your barrel don't let it get hot. (Too hot to touch is too hot to shoot). If you don't, then burn it up. You'll never convince one to do the other.
I don't like getting shotgun barrels hot, (shooting a fast round of Trap doubles on a hot day), only because you'll get a ton of plastic fouling in the barrels that's a bitch to clean out. (Using wire brushes on cordless drills, along with all the other bullshit). I hate cleaning guns as it is.
For AR-15 platform rifles, this Caldwell unit that fits into the magazine well works very well, and it has a rechargeable Lithium Ion battery. It will cool down a hot AR barrel fast. Like while you're reloading your magazines.
But as was mentioned, on a really hot day you're not going to be able to get it cooled down regardless of what you do. Unless you use some type of refrigerant or CO2. And that gets expensive.
Caldwell AccuMax Barrel Cooler AR-15
Caldwell Accuamx AR-15 barrel cuts the barrel cooling time in half. Using a high pressure fan with dual motor bearings, wind is tunneled through the...
www.midwayusa.com
Rifle Barrel Coolers
Rifle Barrel Coolers improve accuracy and simulate cold bore rifle shots
www.lifelinereproductions.com
I remember my first time on the hide alsoJesus Christ, all the bitching and moaning is like listening to a bunch of teenage broads on the rag, whining about who got fucked on prom night......
If you care about your barrel don't let it get hot. (Too hot to touch is too hot to shoot). If you don't, then burn it up. You'll never convince one to do the other.
I don't like getting shotgun barrels hot, (shooting a fast round of Trap doubles on a hot day), only because you'll get a ton of plastic fouling in the barrels that's a bitch to clean out. (Using wire brushes on cordless drills, along with all the other bullshit). I hate cleaning guns as it is.
For AR-15 platform rifles, this Caldwell unit that fits into the magazine well works very well, and it has a rechargeable Lithium Ion battery. It will cool down a hot AR barrel fast. Like while you're reloading your magazines.
But as was mentioned, on a really hot day you're not going to be able to get it cooled down regardless of what you do. Unless you use some type of refrigerant or CO2. And that gets expensive.
Caldwell AccuMax Barrel Cooler AR-15
Caldwell Accuamx AR-15 barrel cuts the barrel cooling time in half. Using a high pressure fan with dual motor bearings, wind is tunneled through the...
Rifle Barrel Coolers
Rifle Barrel Coolers improve accuracy and simulate cold bore rifle shots
Never. Far too meaningless to trouble the experts with.Don’t be scared to share all that data you collected
I don't know how much you, "remember"? But this place wasn't like this 15 years ago. Mostly because the people who are here acting like this today, weren't old enough to own guns then.
I started writing a post with all kinds of data on what temperatures cause stainless steel to expand, deform, increase erosion, etc., but, it got to the point where the data became irrelevant and/or boring. So, I erased it.
Instead, I am going to provide these links:
precisionrifleblog.com
precisionrifleblog.com
I'm not sure how many of you are familiar with The Precision Rifle Blog. I find his articles informative, accurate, and relevant. Also, his writing can be comprehended much easier than mine.
Instead, I am going to provide these links:
Practical Tips to Extend Barrel Life
With the number of “overbore” rifle cartridges popular today, barrel erosion is becoming a hot topic...
precisionrifleblog.com
How Fast Does A Barrel Erode?
A match-grade barrel is a big investment for many shooters, so how much life you can expect from it...
precisionrifleblog.com
I'm not sure how many of you are familiar with The Precision Rifle Blog. I find his articles informative, accurate, and relevant. Also, his writing can be comprehended much easier than mine.
There appears to be a bit of jovial bantering going on in this thread/post and hopefully I can share my experiences with shooting and not piss too may people off.
A majority of my shooting has been across the 'Course' (I know I sound like a broken record) with a Remington 40-XC action and stock, chambered for NATO 7.62 which was what was stamped on the 24" long twist in 12" SS barrel that was button rifled. Subsequent barrels were SS and varied from 24 1/2" to 25 1/2" long and rate of twist 1 in 11" down to 1 in 10" and cut rifled. The contours have mimicked, for the most part, what was on the 40-XC originally and/or near an MTU taper. Weight, balance and sight radius factored into the length and contour.
During rapid fire at 200 yds. after two sighters, you have 60 seconds from the time the target hits the top of the carrier to get off 10 sighted (HOPEFULLY) rounds. With a bolt gun, that required charging the magazine with another 5 rounds using a stripper clip after the first five were fired.
After the 60 seconds the target goes down and the the shots are scored. The target is then 'cleared and it is run up for the 2nd string of another 10 hopefully sighted rounds. That whole process probable takes less time than for me to write this. On a summer day the barrel would be noticeably warm but still able to be touched.
At any rate, of interest is what ledzep said about seeing through the heat waves. Almost all the shooters I remember in the past had a elastic type black barrel band or strap that ran from the front sight to the receiver to dissipate heat. It was called a mirage band and allow you to see through the 'heat waves'
After the 300 yd. rapid fire stage, on a hot July or August day, with the noon day sun beating down on you the barrel would be touchable but probably not grabbable.
At the 600 yd. slow fire stage few if any shooters would chamber a round unless prepared to touch it off within a moment or so. It could be put in the magazine but not chambered. The thought was to let air circulate through the barrel and a chambered round would block the air flow. Many shooters would also raise the muzzle higher than the butt to facilitate air flow I guess.
So yes barrels get hot to the point of not wanting to grab it but that was the nature of the game when shooting across the 'Course'. I do remember in some mid-April matches and some in late September when there was a chill in the air that the barrel warmth was welcome and you could wrap your trigger finger around the barrel and keep it, the finger flexible.
A lot of the barrels were SS back when I was actively going to matches and cut rifled with the thought they would be less prone to 'wearing out' prematurely or have 'barrel wander' due to heat.
A majority of my shooting has been across the 'Course' (I know I sound like a broken record) with a Remington 40-XC action and stock, chambered for NATO 7.62 which was what was stamped on the 24" long twist in 12" SS barrel that was button rifled. Subsequent barrels were SS and varied from 24 1/2" to 25 1/2" long and rate of twist 1 in 11" down to 1 in 10" and cut rifled. The contours have mimicked, for the most part, what was on the 40-XC originally and/or near an MTU taper. Weight, balance and sight radius factored into the length and contour.
During rapid fire at 200 yds. after two sighters, you have 60 seconds from the time the target hits the top of the carrier to get off 10 sighted (HOPEFULLY) rounds. With a bolt gun, that required charging the magazine with another 5 rounds using a stripper clip after the first five were fired.
After the 60 seconds the target goes down and the the shots are scored. The target is then 'cleared and it is run up for the 2nd string of another 10 hopefully sighted rounds. That whole process probable takes less time than for me to write this. On a summer day the barrel would be noticeably warm but still able to be touched.
At any rate, of interest is what ledzep said about seeing through the heat waves. Almost all the shooters I remember in the past had a elastic type black barrel band or strap that ran from the front sight to the receiver to dissipate heat. It was called a mirage band and allow you to see through the 'heat waves'
After the 300 yd. rapid fire stage, on a hot July or August day, with the noon day sun beating down on you the barrel would be touchable but probably not grabbable.
At the 600 yd. slow fire stage few if any shooters would chamber a round unless prepared to touch it off within a moment or so. It could be put in the magazine but not chambered. The thought was to let air circulate through the barrel and a chambered round would block the air flow. Many shooters would also raise the muzzle higher than the butt to facilitate air flow I guess.
So yes barrels get hot to the point of not wanting to grab it but that was the nature of the game when shooting across the 'Course'. I do remember in some mid-April matches and some in late September when there was a chill in the air that the barrel warmth was welcome and you could wrap your trigger finger around the barrel and keep it, the finger flexible.
A lot of the barrels were SS back when I was actively going to matches and cut rifled with the thought they would be less prone to 'wearing out' prematurely or have 'barrel wander' due to heat.
