Barrel cooling

[Nature Boy]

@Nature Boy , are you using the fan during F-Class matches? Have you seen accuracy/precision issues as your barrel heats up?

Thanks.

I have not used a fan and this weekend will be the first time for me to shoot a match in the 90’s. I’ll let you know

 

[Coal Dragger]

It would be interesting to see some data on velocity and or accuracy/precision as a function of barrel temperature. Maybe taliv has something along those lines. I don't shoot PDs but I see that it would be a problem if the barrel temp is affecting accuracy/precision. I used to shoot a fair amount of F-Class matches in Hawaii with the ambient temperature in the 90s and never saw an issue as the barrel got really hot on 22 shot strings. I had Krieger barreled rifles that are single point cut so maybe that's part of it.

Your Krieger barrels were cut rifled, which is a low stress method of imparting rifling. Plus it’s very likely that Krieger then stress relieved the barrel too. It seems that a properly stress relieved barrel of any type will often not display the kind of impact shifts as they heat up that inferior barrels will.

 

[Demi-human]

I have used the Coleman inflator and a piece of rubber hose that presses tight to the chamber. It works. It is too loud, however. Which seems strange to say when one is out using firearms.
I will shoot ten and rig the hose and then check the hundred yard target. When I get back to the bench I shoot again. I haven't had any point of impact shift in one hundred and fifty rounds in a session. But to be honest, I am going to shoot it whether it's cooled or not. (My nieghbors love me.)
I haven't done any laser thermometer tests, yet, but I do have one.

Maybe mine is getting long in the tooth. But the noise is irritating. I wouldn't use it at a range with other humans, just to be polite. I just blew up a donut pool float, made to look like a doughnut with sprinkles, with the inflator and the same batteries that have been in it for years. So it does have a loooong runtime.

I have a similar inflator that runs off a twelve volt car plug. It is as loud as a vacuum and does a tremendous job! I think that would work nice, but one would need a small tractor battery and adapter.

 

[Offfhand]

Not to get too far off the subject, but earlier on in this thread I mentioned getting off up to a sustained 7 shots per min in the PD patch. This claim was challenged by a couple of PMs, saying no way. So here is part of the secret of sustained aimed fire, even with the single shot bolt rifle shown here: I shoot right handed but with bolt operation on the left side, which speeds rate of fire considerably because of no need to release right hand to operate. Action loads from left side but ejects from right side, which speeds up operation further. Also have large supply of ammo in nail bag (shown) for quick access. Yep, the barrel gets plenty hot, but a hot barrel is a happy barrel.. .

 

[ACES&8S]

Twiddling my thumbs and watching the clouds blow by while waiting for my rifle barrel to cool between shots, I was wondering why not use a $15 Coleman QuickPump 12V rechargeable air mattress pump to cool the rifle barrel "quicker"? I searched the Internet and see other barrel cooling fans at $50+ for sale. Any reasons why not use the Coleman version, as I already have one with all the misc. nozzle sizes?

Sounds solid, will probably work real good.
What we do here is sort of by convenience. I have a big air compressor for the shop, which has
an air supply just inside the door at where we shoot from outside. It does real well cooling things
down as well as blasting out black powder barrels or the nipples kept clean.
I used to run AR & AK & stuff hot when I was new in this, now I shoot steady controlled burst
which are more accurate but still heat up the barrel.
A side note, I would stay away from any kind of cooling that flash cools them.

 

[Nature Boy]

@Nature Boy , are you using the fan during F-Class matches? Have you seen accuracy/precision issues as your barrel heats up?

Thanks.

One guy brought a fan last weeked (~25 shooters). He had it pointed at himself instead of the rifle. Considering how hot at humid it was I don’t blame him

 

[Nature Boy]

So here is part of the secret of sustained aimed fire, even with the single shot bolt rifle shown here: I shoot right handed but with bolt operation on the left side, which speeds rate of fire considerably because of no need to release right hand to operate.

I noticed 2 fellas at the High Power match last weekend who were left handed but had their bolt on the right side. They were both expensive custom rigs so I knew there had to be a reason. Thanks to your explanation I know why now. Might be more of an advantage in benchrest since High Power still needs to wait on pit service

 

[<*(((><]

I would think one could make a radiator out of 3/8” coiled copper line to fit a cooler and with an inlet and outlet plumbed in and place in a cooler, fill the voids of the serpentine copper lines with water and freeze it. Just have to calculate or trial and error an air pump to work.

I might have to make me one of them.

 

[HB]

Sounds like a ton of work. I would bring a 22 and shoot that as the 308 cools, because that’s what I do.

 

[Newtosavage]

Twiddling my thumbs and watching the clouds blow by while waiting for my rifle barrel to cool between shots, I was wondering why not use a $15 Coleman QuickPump 12V rechargeable air mattress pump to cool the rifle barrel "quicker"? I searched the Internet and see other barrel cooling fans at $50+ for sale. Any reasons why not use the Coleman version, as I already have one with all the misc. nozzle sizes?

That's actually a darn good idea.

 

[Offfhand]

I noticed 2 fellas at the High Power match last weekend who were left handed but had their bolt on the right side. They were both expensive custom rigs so I knew there had to be a reason. Thanks to your explanation I know why now. Might be more of an advantage in benchrest since High Power still needs to wait on pit service

Having the bolt handle on "off side" Left bolt for right hand shooter. or reverse, has proven so fast and deadly that it gets habit forming. Which is why I've had a few more varmint rifles built the same. A .22/250 by Kenny Jarret, .220 Swift by Dakota and a 40-X Rem. in .223 Rem,.The Jarrett and Dakota are single shots and 40-X has a magazine. The accelerated rate of fire quickly gets them sizzling hot (Spit sizzles on barrel like on a hot iron.) in a busy PD patch but a quick blast from winter Breeze cooler sets them right again.

 

[Legionnaire]

I recently ordered the December 2008 back issue of Handloader magazine because I wanted to read Gary Sciuchetti's article, "Developing the Most Accurate .308 Winchester Load." Lo and behold, in the middle of the article, there is a picture of a battery-powered Coleman air pump that Gary used to cool the barrel during extended range sessions. Guess the idea has been around for a while!

 

[Demi-human]

Great minds, you know!

 

[CoalTrain49]

I use two rifles. 20 rounds thru the heavy barrel and 10 thru the light barrel.

I don't shoot more than 100 rounds in a normal 2 hour range session.

Sometimes I take 3 rifles.

 

[joneb]

Sounds like a ton of work. I would bring a 22 and shoot that as the 308 cools, because that’s what I do.

Me as well, not always 22 lr but just the same, I keep the bolt open on the rifle with the warm barrel.

 

[doubleh]

Wow, thanks for all the responses.
For those asking why I don't just relax, I have a reloading bench in the house, a shooting bench with 15 yard to 180 yard shooting range out the back of the house, and when I'm working up loads I want to shoot a string of 3 to 5 shots of each load and continue developing loads. Yes, I go change targets sometimes, or go feed the horses, or go collect eggs, whatever... but I always get back to waiting for the barrel to be "cool to the touch" between each shot.
I see nothing in the responses to prevent me from using the Coleman blower, so I'll see how quickly that reduces the "barrel cooling time". Thanks again

You already have the pump so why not try out your idea. Nothing ventured, nothing gained and it's basically a freebie. If I were interested in something like that I have a couple of 12 V tire pumps that deliver plenty of air flow that I could experiment with but I usually take three or four rifles to the range and switch them out. Load development on one or two and one or two just for fun.

 

[magnatecman]

Are you shooting for groups? What happens if you don't let the barrel cool between shots? I was shooting a 6.5 PRC the other day and saw no difference in bullet velocity from the first group starting out with the barrel around 65°F (ambient temp) and ending with the last group (same load) where I couldn't keep my hand on the barrel for more than a second or two. According to NASA, the barrel could have been around 100°F hotter or more by the end of the last group. The current consensus is that we start to feel pain when our skin reaches a temperature of 110°F and that takes about 1 second for steel that's at 160°F, 2 seconds for steel at 150°F and three seconds for steel at 140°F. These are rule of thumb values (ha! ha!) since heat transfer from a barrel to a hand is a very complex issue.

So back to my original question, what are we trying to avoid by keeping the barrel cool? What is cool? How does this relate to real-world use of a rifle/load e.g. hunting?

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What did you have to stop and eat a sammich before that last group? Very nice numbers there too!

 

[George P]

Folks are pretty ingenious, sounds like that guy is one of them...My wife's friends take their UTV on long desert trips. They rigged up an air pump/clear tubing-hose contraption that pulls air in, routes the air through a hose coiled up in an ice chest mounted on the rear of their rig and then pumps it into their helmets as an AC unit. They swear it makes a 200 mile run through the Mojave comfy...

Some folks around here just buy the UTVs with doors and AC and heat. Stay cool all summer and warm when it gets cooler.

 

[Demi-human]

Some folks around here just buy the UTVs with doors and AC and heat. Stay cool all summer and warm when it gets cooler.

We call 'em trucks around here. They're handy for hauling a load of guns and shooting gear!