Cooling the barrel during scope sighting-in

[FITASC666]

Is there any harm in using ice pack or bags of ice to cool the barrel in hot weather to reduce the waiting time between shots when sighting in a rifle? The barrel is on a Steyr Mannlicher short stock. It also has a torsade shape from the manufacturing. Your advice or recommendation is valued.

 

[Robert Wilson]

I have never used ice. Compressed air is somewhat popular with the ballistics labs; just a hose connected to a tank and run in to the chamber. This has never caused any harm that I have heard of. I wouldn't think ice would either.

 

[RoostRider]

A barrel considerably colder than normal may display as much, or more inaccuracy as a barrel hotter than normal.....

I would not indulge in that practice for that reason, as well as the sheer inconvenience of it...

It will not harm the barrel unless you are applying it to a 'really hot' barrel....

 

[PT1911]

just take about 2 minutes or so between shots in the shade... slows down the process but I cannot imagine putting ice on a hot barrel... too much of a fear of warping the barrel in some way... it may be completely unfounded but not something i want to test... waiting a couple minutes works just fine for me.

 

[1911Tuner]

On cool days, the barrel only takes a minute or two between shots to cool. On hot days, I use a wet towel...not sopping...to lay on the barrel to pull heat out of it. One way to cool it off faster regardless of the ambient temperature is to stand it up so that the heat will rise through the muzzle...like a stovepipe. Cuts down on cooling time about 50%.

 

[PT1911]

now that is a brilliant idea... had not thought about the virtical benefit.

 

[1911Tuner]

PT...I have my moments.

Here's another one that works for me most of the time. The bane of rifle shooters everywhere is the first shot out of a clean barrel printing out of the group.

This is due mostly to traces of solvent and oil in the bore. No matter how many times you push a dry patch through...there's always a little remaining.

The cure...Pass a clean patch soaked with denatured alcohol through, followed by a dry patch. Most rifles will put the first shot in the group. If not exactly...much much closer than before.

 

[jimmyraythomason]

"One way to cool it off faster regardless of the ambient temperature is to stand it up so that the heat will rise through the muzzle...like a stovepipe. Cuts down on cooling time about 50%." This is the method I use.

 

[1911Tuner]

Jimmyray...You Bama boys gotta be resourceful at findin' ways to beat the heat.
I got a couple friends around Leighton and Muscle Shoals. They report that the temperatures are pretty brutal in July and August.

 

[JimKirk]

Air Pumps

I use one those air mattress (12 volt) pumps like you pump up an air bed with.
Most have a small nozzle that will fit inside the action of a bolt gun or other type. Most have long cords that let your truck(car,ATV or wheel chair) be near. Turn the pump on only long enough to bring barrel down to air temp....works faster than self cooling. Oh don't laugh about the wheel chair ... I know a guy who is chair bound and he loves to shoot..has a 12v outlet on his chair ..a small fan...to keep him cooler ...works for the air pump too!

Jimmy K

Pump is of the squirrel cage type ...not the piston type.

 

[PT1911]

I will have to try the alcohol trick as well... btw... the heat is stifling right about now in the Talladega area at least.

 

[Delmar]

I normally run a patch soaked with solvent-gun scrubber or some such, thru the barrel before the first shot, and leave the action open between shots for a few minutes to help cool things off. If the barrel gets more than slightly warm to the touch, I put that weapon aside, pick up another and follow the same proceedure. Thats one of the many great things about owning a few rifles

 

[jimmyraythomason]

It does help to sight in multiple rifles at a single outing so they can be rotated.

 

[NotSoFast]

Standing the barrel vertical may be an option at the range you shoot at. However, the one I shoot at would have my head for pointing the muzzle any direction but directly down range.

 

[oneounceload]

One way to cool it off faster regardless of the ambient temperature is to stand it up so that the heat will rise through the muzzle...like a stovepipe.

And with the action open, it will do it even faster.....

 

[DiTzMaN]

+1 Jimmyray. Just take a couple with you to the range. Maybe a .22 to do some plinking while you are waiting ))

 

[dubbleA]

I have a small squirrel cage blower I use to cool the barrels off and have also used CO2 sprayed through the bore to quickly cool em down.

 

[dmazur]

Not trying to ruin anyone's fun, but I believe you'll get condensation if you cool a barrel below dew point...and a lot of condensation might be something you want to wipe out before resuming shooting.

Also, I watched fabricators "warp" steel to fit with a torch, followed by differential cooling. While the temperatures are undoubtedly hotter, it might be possible to warp a barrel slightly with all this hot/cold stuff...and I don't think I want to warp a barrel.

Wet rags, forced air, sure. I'm not so comfortable with dry ice, CO2, or propane (liquid.) With that much of a temperature difference, you just might throw a warp into it.

 

[Jim Watson]

An air blower would be as far as I want to go with a target rifle, maybe a wet towel on a military rifle. No ice packs for my barrel, save them for my shoulder if shooting more gun than I should.

Some years ago I read an article plugging a barrel with a cooling system built in, a high tech version of the water cooled machine guns, only using refrigerant. Bulky and expensive.

 

[1911Tuner]

And with the action open, it will do it even faster

Well...that was kinda assumed...

 

[The Lone Haranguer]

I would think suddenly quenching the barrel might alter its vibration characteristics.

 

[JimKirk]

dubbleA,
Glad to see that I'm not the only one using a squirrell cage fan! Lots of air ...little energy use. Cools quick but not so quick as to cause warps.

Jimmy K

 

[Bart B.]

Unless your barrel's not stress relieved properly or poorly fit to the receiver, it doesn't matter how hot it gets. These are the two main reasons point of impact changes as the barrel heats up.

Barreled action steels have the same resonant frequency and structural integrity regardless of how hot they get from normal shooting. Should one start having a different resonant vibration/whip frequency, it may well have cracked or ruptured from being hot enough to soften and significantly weaken the steel.

Test barrels at arsenals testing match ammo get shot once every 15 to 30 seconds producing 100 or more shots per test group at 100 yards about 1/3 MOA; at 600 yards they're a bit over 1 MOA.

Biggest problem with hot barrels is letting a chambered round sit in the chamber more than 15 to 20 seconds before shooting it. The powder gets too hot and burns faster producing higher muzzle velocity. But it's usually not noticed at ranges less than 200 yards.

Here's a test group of 20 shots at 800 yards starting with a cold barrel. Shots were fired about 15 seconds apart. Note shots 1 and 2 are a bit low as there wasn't enough powder fouling in the barrel to increase pressure a tiny bit to increase muzzle velocity just enough to make bullets print an inch or so higher.