I read an article many years ago regarding cooling barrels during load testing. Until recently I didn't have the ability to do this because I always had to go to a public range where I didn't have the equipment to cool a barrel. I now have a range on our ranch next to our shop building. So I have been experimenting with putting compressed air through the barrel after every 3 to 5 rounds. It seems to provide more consistency when I am doing load development for each rifle. I also do a very light cleaning of the barrel after each 10 rounds.

Any thoughts, pro or con?

Thanks.

I take a fan with me to the range. I leave it run on the gun all the time I'm there. Seems to shorten cooling times between shots.

Droptine

I am very interested in you experiments. It is so incredibly hot here in Florida in the summer, barrel's heat up to "no go" temp with three spaced shots. It takes a fair amount of time to cool.

I have learned that they cool better up and down, which exposes more barrel to air movement. But the use of compressed air is very innovative. How do you introduce it into the barrel? How long do you use it? Does it leave any water in the barrel?

Cleaning above 10-20 shots is probably a good idea. After cleaning, do you "foul?" Kudude

I've actually poured ice water thru the barrel while prairie dog shooting.....It's a tad messy however.

I remember a artical in a gun rag a couple years ago on a system someone was pushing that blew compressed air down a rifle bore. I think the system used CO2 and as I remember it only took a couple seconds blast to cool down a hot barrel on a dog town.
I never did see any follow up on it and don`t know if it was marketed or not.

If you are shooting where you can get your vehicle close by I use the ac to keep my guns cool. I take about 3 guns to the range. When one is hot it goes inside the pickup with tha ac on high. I close all the vents except for one to get maximum wind velocity through that vent. I romove the bolt from the gun and position the gun so the wind from the ac is blowing right up through the action and barrel of the rifle. Doesn't take very long at all and you have a cold barrel again.

quote:

I've actually poured ice water thru the barrel while prairie dog shooting.

I gotta wonder at what point the thermal shock from this practice could harm a barrel...??? Seems like some varminters let 'em get sizzling hot, and boiling water hot+ice water would seem to be in warpage territory to my (admittedly in-expert) mind.

Kudude,

I grew up on the coast of Texas so I can appreciate your Florida climate. Since I am just outside my shop building the amount of air used is of no great consequence. I have a large capacity shop size air compressor that supplies all I need. However, I have noticed that high pressure airflow through the barrel does not seem to be a great deal more effective in cooling. I use a very inexpensive air gun with a pointed brass tip inserted in the muzzle of the barrel, and remove the bolt. I have given some thought to running a very thin tube with a bunch of side holes to get better air distribution. However, it would have to be really thin to allow the air a path out of the barrel, especially if it were used on a 223 or 22-250, or even a 25-06. The air gun is working great for me but I am sure it can be improved upon.

If you are in the situation of being at an outdoor range with no power available, I would think that one of the small air compressors that plugs into your cigarette lighter would accomplish the same end result.
(Don't run down your car battery).

Also, I have notice that Sears has some very small and lightweight AC air compressors that would be perfect if your range has an AC recepticle close.

I have not done a scientific study of any type to determine factual conclusions. But after 40+ years of shooting and 30+ years of handloading I feel certain that bringing the barrel temp down to a fairly consisten level will give you more accurate load development. I believe that there has been a lot of written material about the importance of "the cold shot." At any rate, I usually just touch the barrel to get close to the same temp.

I would suspect that a cooking thermometer could be used. Or perhaps one of the Indoor / Outdoor digital thermometers that has the very small sensor that you put outside your window would suffice. Several years ago my son raced a car on the drag strip. I observed many of the better cars had a crew member use an infrared sensor to measure the temperature of the track surface so that the proper air was put in the racing slicks to get the best traction. At that time, the infrared sensor was around $100. They may be even less today and it would be a great way to measure the barrel temp without attaching anything to the barrel.

Enough of my ramblings. One of my frustrations when going to the public range was the amount of down time waiting for barrels to cool. If there were lots of "gun culture" people around you could always just burn up some time visiting. But otherwise it was wait, wait, wait. So the compressed air has been great. I have found no indication of any water or moisture in the barrel. Yes, I do fire a fouling shot after each cleaning and then cool the barrel again.
Of course, before I store any rifle I clean the barrel thoroughly and patch it with a very light oil to protect it - very important in a humid climate!

The article that I originally read was in a law enforcement magazine and it was making reference to an armorer / gunsmith that built and maintained SWAT precision rifles. But I think he was using some other gas that was actually much quicker in cooling. For my purposes, air works just great.

Hope this has helped.

Good shooting and Merry Christmas!

What about the compressed air in a can ? Like the one you use to blow off your keybroad. Know it is a small can but maybe 2 or 3 cans would be enough . Just my 2 cent's

My standard practice is to wait 2 minutes between each round and 10 minutes between each 6-shot string. (With the bolt and/or action open.)

This has always worked for me.

The air used for cooling gets warm and thus, drier when passing through the barrel. No risk of humidity condensing, only when you do it the othet way round, that is, cool warmer air.

I hearded that using compressed air to cool is quite common practize with many gunsmiths and manufacturers here. After all, air was used to cool internal combustion engines of vehicles for decades.

I'm not real scientific with it but this is what I do.

I take a probe thermometer along to the range.

While the rifle sits in the rack I stick it in the end of the tube. It will give me a temp that is where the tubes temp is b4 starting to shoot.

Then I will after my string put the gun back in the rack and the therm back in the tube. I try to not shoot again until the temp is back to its starting place.

Good luck

Mark D

there is also some temp strips out there that one can get to afix to the tube, read about them but never tried them.

Most of my rifles are SS. For the last several years I have used a wet towel which I drape over the barrel between shots. A couple of minutes cools the barrel way down. When the ambient temperature rises above 80° there isn't much point in shooting anyway as you can't tell much about your rifle or loads at that point.

Having worked with compressed air and designed many compressed air and drying systems all of my now completed working life, let it be known that on a hugh percentage (98%) of compressed air systems there is water in those lines.Hot or cold carbon steel barrels and water form rust it's just a matter of degree.

Obviouly there is little to worry about if you can pour water down your tube and have no ill effect.

Let's say that the compressed air treatment is all right. How long after you blast the inside of the barrel before the outside of the barrel and inside temperatures are normalized?

If there are to be any temperature differential ill effects it might even be more pronounced in a stainless barrel because of the much slower heat transferre.

Steve's method sounds as good as any to me.

You might try anti freeze inside and out followed by one cleaning patch.
[LIST]Some other options are:

Shoot slower!

Take more rifles with you!

For those in Texas or Florida who are plagued with heat move to the UNITED States. roger

Old age is a high price to pay for maturity!!! Some never pay and some pay and never reap the reward. Wisdom comes with age! Sometimes age comes alone..

quote:

Originally posted by Bob338:
Most of my rifles are SS. For the last several years I have used a wet towel which I drape over the barrel between shots. A couple of minutes cools the barrel way down. When the ambient temperature rises above 80° there isn't much point in shooting anyway as you can't tell much about your rifle or loads at that point.

That would mean going to the range to work up loads is pointless to me about 9 months out of the year, as I live in Phoenix. It was 79° here yesterday! On really hot days (above 110°) I've burned myself on the forend screw on my NEF; the wood is warm but that little screw picks up the heat from the barrel and gets real hot.

For shooting, I've found that Varget seems pretty consistent in my .223 when the temperature varies. The biggest thing I've noticed is the POI rises or lowers depending on how hot it is. I believe they shoot higher in the really hot weather. But a portable fan would do wonders to "cool" the barrel back down to starting temperatures.

What about a patch or two soaked with IPA down the bore?
Or a cloth on the outside of the barrel "soaked" with IPA?
CO2 is a good coolant because it's an escaping gass and absorbs energy.

quote:

Originally posted by The Dane:
CO2 is a good coolant because it's an escaping gass and absorbs energy.

It can cause super cold spots on the steel that instantly draw moisture out of the air. That could be real bad in Florida. roger

I used wet towells - at least until folks started looking at me oddly. It works, taking lots of heat with it. Since the towell doesn't touch all the barrel evenly, however, I let it sit a bit longer. I figure the cooler parts will give the heat somewhere to go and it'll even out.

I rack the rifle muzzle up, with the action open. This creates a chimney effect, with the hot air rising around the barrel and through the bore, drawing cooler air in at the bottom, heating it as it rises, then taking the heat out the top.

I've considered a small battery-powered aquarium filter pump to feed the air into the action, speeding up the natural convection currents, but haven't done anything about that, yet. It wouldn't be as efficient as a 110v or 12v pump, but it would likely be smaller. I take too much crap to the range as it is.

When I'm not in a hurry, I take a nice Anschutz 22 Magnum to take up the cooling time.

Think of the cooling requirement as nature telling you that you need more rifles so that you won't be bored while they cool...

Jaywalker

bring a few rifles along,when one gets warm start shooting the second one...shouldn't be that much of a problem?

I bring five rifles to the range. Never less that four. I fire two or three shots and then go to the next one. By the time I write down where the shots went the next one is cool.

Hey Savage,I never owned a Savage rifle are the accurate?

Some of the BR shooters, that come to our matches, have put together a nifty little system for cooling barrels between relays.
They use Sinclair bore guides attatched to clear tubing and a DC bilge pump. They put some sort of green coolant, in a jug, in a cooler with the pump and, circulate it through the boreguide and out of the muzzle back into the jug. Looks to be really portable and easy.

Hey SD Shooter, Good thread.

quote:

Originally posted by Jaywalker:
...I rack the rifle muzzle up, with the action open. This creates a chimney effect, with the hot air rising around the barrel and through the bore, drawing cooler air in at the bottom, heating it as it rises, then taking the heat out the top...

Same here. If I'm going to shoot three 2-shot groups or two 3-shot groups, the rifle is positioned just as Jaywalker mentioned between groups.

Once I get whatever number of shots I want through the barrel (1, 2, 3, or 6), I go right on and get some Bore Cleaner in the barrel. I let it lay on it's side for a couple of minutes and then roll it over so the other side is down. After a couple more minutes, I run the patches through it to remove the Bore Cleaner, Lube the Bore and finish it off with a couple more patches to remove any excess lube. Then I do as Jaywalker mentioned and set it so any remaining barrel heat will draw the ambient air up through the Bore.

Since probably 75% of my hunting is done above 60deg, I don't let 80deg ambient temps stop my Range Time. Just have to go a bit slower, shoot some more 22RimFires while waiting and have a lot of cold water to drink.

May have already been mentioned, but how about those compressed air bottles that you get at the computer store to blow off keyboards, etc? I bought a case and they work great! Got the little straw on the end that fits quite nicely in the barrel. Hold the can right side up and blow cool air in....hold it upside down and it blows out cold air. Works like a charm and best of all, it is the size of a WD-40 can or thereabouts, depending on which brand you buy.I don't have to take a compressor to the range.

Take it easy.

you know, some sort of rechargeable bottle, like a air bottle for a paintball gun might work. with an adapter, valve, and hose you could use that, and charge it up on teh air compressor at home. Dunno how long it would last, maybe not too long, but it would be better than spending money on air cans every now and again. Heck, maybe even if you got it refilled at the paintball shop it might not be too bad.

Another option too is the propellant cans for airbrushing. The caps come with a screw in valve of sorts, and the hose and nut on teh end is small enough to fit in the chamber.

http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LX8182&P=0

That might last longer than the keyboard cleaner.

Saw a guy running a bore swab soaked in 50% isopropyl alcohol in & out of barrel. Claimed it cooled barrel, got out minor fouling, and evaporated any condensation. Don't know if he cleaned/lubed after. This is untried by me, can't attest to whether it's B.S.

quote:

Originally posted by shootaway:
Hey Savage,I never owned a Savage rifle are the accurate?

YES!roger Didn't mean to step on U Sav.99

quote:

I use a very inexpensive air gun with a pointed brass tip inserted in the muzzle of the barrel, and remove the bolt.

If it was me, I'd blow from the breech towards the muzzle so the loose stuff blows out, not into the action.

quote:

Originally posted by shootaway:
Hey Savage,I never owned a Savage rifle are the accurate?

Not the ones I have!

The 99f's that I have had for a long time are 1.5 to 2 moa rifles. Thats minute of buckskin however around here and better. I like those rifles a lot.

I had a new M112 or whatever in 270 WSM and sent it back for pressure issues and other problems including 2 moa and worse accuracy. Savage did not read my letter but returned a test target and polished the chamber. That cost me $300 as I dumped it.

Now I have a Savage ML10 11 and it's reasonably accurate and quite reliable. This rifle is very heavy but at least it goes off which is a revilation to me.

Quikly cooling any steel will cause great harm if you dont know the parrameters of what your dealing with and an extreamly hot steel can warp, and or spider crack when rapidly cooled (Ice Water) DO NOT DO THIS!!! It's a waiting game of shoot and wait dont rush cooling your treasured firearms barrel use the rotation method.

Ted,

Do you have some support for your assertion that water-cooling will harm the steel? People have been doing it for years...

Jaywalker

I have an '95 GMC van dedicated purely to shooting, with a benchrest, a loading bench, and a cleaning/gunsmithing bench all built-in (and, it's air-conditioned!).

I shoot in high-desert Nevada, and in the summer heat a rifle barrel takes FOREVER to cool. If much shooting is ever going to get done, some method of artificial cooling must be used, and I have adopted the ice-water method from a 2-gallon thermos jug for the job.

Fifteen seconds of ice water running through the barrel gives me a COOL tube. Under the benchrest, I have an "air pig", a compressed-air storage tank, equipped with a hose and valve which allow me to blow compressed air through the barrel from the breach. Ten seconds of compressed air gives me a DRY tube, as well as a cool one. There's enough residual heat to instantly evaporate any moisture in the barrel, and this is just not even a consideration, particularly in the extremely low humidity in these parts.

I have a digital probe-type thermometer, which has informed me that when I think the tube is hot enough to need cooling, it is ONLY in the area of 180 degrees Fahrenheit. My barrels are apparently unharmed by quickly reducing their temps by a grand total of only maybe 100-120 degrees. This is a paltry amount of change in the world of steel. Not only are the barrels undamaged, but I find that a barrel "conditioned" for cast bullets is also not affected by cooling in this manner. Point of impact is not affected, either, and I save a LOT of time waiting for barrels that never really cool when it's an ambient 100-plus degrees on the range.

Considerations of "instant rust" are unimportant. The reaction definitely sets in immediately, but the first shot will absolutely remove the molecule-thick oxidation. Note that I ONLY cool artificially when shooting is going to continue. When I've finished with a rifle for the day, it's allowed to cool naturally, and I have never had a problem of any description doing it this way.

Note that rifles fired with my cast-bullet loads often go MONTHS and hundreds of rounds without being cleaned or otherwise messed-with internally, and there has never been any damage, rust, or other nasty effects on them from "forced cooling". The long time between cleanings is precisely to avoid disturbing the desireable "conditioning" of the bore for the cast bullets, and it IS important.

The shooting van in an early stage of development can be seen in "Special Projects" at

http://www.castpics.net

but many additions have been made since then.

Merry Christmas!

Brassb, I don't know about swabbing your barrel with alcohol (not something I do) but I use it at the range on a rag for cooling the barrel down. It's quick and cheap. I just go to Walgreen's and pick up a big bottle of rubbing alcohol for a buck or less, and then when the barrel gets hot I wet down a rag liberally and run it up and down the barrel. The alcohol wicks the heat off the barrel in a hurry. Cuts down on your range time by quite a bit.

My $.02

Savage 99 does it like I have for years. I take at least three rifles, sometimes 6 or 8. I shoot one then pick up another. I also wait at least one minute between shots. I read somewhere that it takes a minute for the gases and unburned powder residue in the barrel to cool enough that it will not harm the barrel with the next shot. Good shooting.

Sometimes I just want to get to the range with minimal gear, shoot the dozen or so shots for load development, and get outa there ASAP.I am gonna try the propellant bottle method. You can screw down the regulator in the cap so it releases air on its own, so you can stuff the hose and walk away for a minute, or if the range goes cold you can set it and step back from your weapon while the RO clears the line.

quote:

Originally posted by Jaywalker:
Ted,

Do you have some support for your assertion that water-cooling will harm the steel? People have been doing it for years...

Jaywalker

I use my knowlege as a 20 year machinist only. Most all steel if not all will stress is heated and cooled quickly.

Ted,

Would it make a difference if the barrels have been stress-relieved before being installed? Most of these barrels we're discussing are hammer-forged or button-rifled, and came out of those processes with lots of stress. Stress relief is a mjor part of the effort before installation.

Also, I'd think temperature would have a lot to do with it. We think of our barrels as "hot" when they're too hot to touch, but they're mostly under 212F (no water boiling). I'll bow to your expertise on this, but I'd think you'd have to get it glowing, at least, before you get into a tempering/annealing zone.

Jaywalker

I think kingfisher has a great method there. I use it as well, and just whiping the barrel down with a rag soaked with alcohol really cuts the range time in half.

quote:

Originally posted by Jaywalker:
Ted,

Would it make a difference if the barrels have been stress-relieved before being installed? Most of these barrels we're discussing are hammer-forged or button-rifled, and came out of those processes with lots of stress. Stress relief is a mjor part of the effort before installation.

Also, I'd think temperature would have a lot to do with it. We think of our barrels as "hot" when they're too hot to touch, but they're mostly under 212F (no water boiling). I'll bow to your expertise on this, but I'd think you'd have to get it glowing, at least, before you get into a tempering/annealing zone.

Jaywalker

Even stress relieved steel can and will accept new stress. All mold steels are stress relieved after and during heat treatment.I have seen heat move all type of metal during machineing I use in plastic injection molds. These molds then run for years at temps usualy bellow 212F these molds will come out of production for repair and maint. from time to time all show sighns of heat related stress. I treasure my rifles greatly it is only my oppinion that quickly cooling a barrel will harm it. The air methods I feel are probably slow enough to not do molecular changes in the steel I however will use the rotation methods and not ever overheat to begin with. The tool steels used in barrels are realy tough 4140 4130 class is oil quench @ about 1600F no worry about hardening but the draw temps are around 400 to 500 not red but verry verry hot. The stainless steels used are air hardening steels that do not require a quick quench to harden and have 400 to 600 draw temps. all of these temperature ranges are WAY higher than that can be achieved by regular shooting. No worrys realy.

Here's what I came up with. Never took any temperature readings or anything scientific like that, but it does blow a steady stream of air down the bore. You can find these things at Wal-Mart, Academy, etc. for blowing up air mattresses, pool toys, and such. I added the 3/8 plastic tubing, which perfectly fits the chamber of my .308 rifle. I also bought a cigarette lighter extension cord at Radio Shack and spliced in about 20 more feet of wire. You could make the hose longer and run it through a cooler full of ice-water, but you might end up blowing droplets of condensation into the bore.

I bought this blower about 15 years ago, so I doubt you could find the exact model today.