how long do I need to let a barrel cool in between shots for a

[AZShooter]

I live in S. Az and had to come up with a faster way to cool a barrel than a wet towel wrapped around the barrel.

The easiest way I have found is to use CO2. You can cool after each shot to simulate hunting conditions. Or you can cool after any number you prefer and really speed up load workups. If waiting isn't for you this is the fastest way to get the barrel back to ambient temperature.


CO2 needs a regulator with plenty of flow. A small rubber hose with end cut at a taper will fit into most chambers for snug fit.

 

[4xforfun]

I live in S. Az and had to come up with a faster way to cool a barrel than a wet towel wrapped around the barrel.

The easiest way I have found is to use CO2. You can cool after each shot to simulate hunting conditions. Or you can cool after any number you prefer and really speed up load workups. If waiting isn't for you this is the fastest way to get the barrel back to ambient temperature.


CO2 needs a regulator with plenty of flow. A small rubber hose with end cut at a taper will fit into most chambers for snug fit.

Try that up north where the misquitos are bad!!

 

[AZShooter]

I'll bet that would be quite an attractant! I do notice that it attracts the small flies we get in August. Having grown up in Upstate NY around the Finger Lakes I know about mosquitoes. Our tiny flies are NOTHING by comparison.

 

[FEENIX]

On average, it's a 10 minutes wait between shots. I keep myself pre-occupied with my .22s or other plinking toy during the waiting period.

 

[MMERSS]

I live in S. Az and had to come up with a faster way to cool a barrel than a wet towel wrapped around the barrel.

The easiest way I have found is to use CO2. You can cool after each shot to simulate hunting conditions. Or you can cool after any number you prefer and really speed up load workups. If waiting isn't for you this is the fastest way to get the barrel back to ambient temperature.


CO2 needs a regulator with plenty of flow. A small rubber hose with end cut at a taper will fit into most chambers for snug fit.

I like it....I've been thinking about taking along my compact air compressor during the summer months just to speed up cooling. F-class rifles heat up fast!

 

[Broz]

In a match one time I was worried about repeated shots and chamber heat. I took a can of the compressed air for cleaning computer key boards. Every few rounds I would stray down the outside of the chamber. This spray is very cold and did cool the chamber metal. Not sure why, but after the match a friend told me all of my misses were the first shots after I strayed.

Not sure what that tells us but I thought I would offer it for what it's worth.

Jeff

 

[SidecarFlip]

Puts me in mind of my favorite sub gun, the MG42. They are supplied with 2 barrels, each barrel at the receiver end has a dovetail that engages a matching dovetail at the end of the receiver and the forestock is hinged so it swings out. When a barrel gets smoking hot, you pull a pin, swing out the forestock, pull the hot barrel (with gloves of course) and fit a cold barrel. The hot one goes in a creek or on the ground to cool off.....

 

[MMERSS]

Every few rounds I would stray down the outside of the chamber. This spray is very cold and did cool the chamber metal. Not sure why, but after the match a friend told me all of my misses were the first shots after I strayed.

Jeff,

How long between shots after cooling? I'm curious if a barrel needs time to equalize the temperature change by say a few minutes to take advantage of the cooling and accuracy.

 

[Broz]

Jeff,

How long between shots after cooling? I'm curious if a barrel needs time to equalize the temperature change by say a few minutes to take advantage of the cooling and accuracy.

On a big caliber when shooting drops or zero. I will shoot 1 or two and wait 10 minutes minimum. This greatly depends on ambient temp and sunshine. But if the bolt handle and the barrel feel the same I call it good.

Jeff

 

[SidecarFlip]

Let us throw this into the equation...

The way the barrel is made should impact cool down time. If a barrel is fluted, it provides more heat transfer area than a non fluted one and barrel coating would also impact cooling off. Any coating on the barrel surface changes the transfer time,

 

[Broz]

I am just starting final load work with my LRKM and testing powder stability. I took the rifle and ammo out and let it set in the cool morning temp of 44* for 1/2 hr. I then fired 3 rounds with the new loads from a cold rifle and cold ammo. 300 gr Berger OTM, 32" fluted Hart barrel , Sendero contour, full house load of N-570 in the 338 Terminator +P. Average velocity from the Magneto speed was 3210 fps. The first and 3rd shot were 3 fps apart.

Jeff

 

[MMERSS]

I am just starting final load work with my LRKM and testing powder stability. I took the rifle and ammo out and let it set in the cool morning temp of 44* for 1/2 hr. I then fired 3 rounds with the new loads from a cold rifle and cold ammo. 300 gr Berger OTM, 32" fluted Hart barrel , Sendero contour, full house load of N-570 in the 338 Terminator +P. Average velocity from the Magneto speed was 3210 fps. The first and 3rd shot were 3 fps apart.

Jeff

I know we are talking barrel temps this thread but I'm interested to see how N-570 MVs at 64 and 24 deg compare to 3210. Your results look promising thus far.

 

[Broz]

I know we are talking barrel temps this thread but I'm interested to see how N-570 MVs at 64 and 24 deg compare to 3210. Your results look promising thus far.

I set these to 905 yards just seeing for myself what cold barrel temp and powder stability will do to the rifle from one day to the next. I will continue testing but this all looked good. I should have final temp / velocity data in a week or so. Hope to get some 65* testing yet today.

As for cold barrel vs hot barrel at 905 yards, all 3 shots could have been covered with an orange. Like I said first shot to 3rd shot in a string with no cool time varied 3 fps on the chronograph.

Jeff

 

[clemens]

Doesn't the rapid cooling effect barrel wear. Being hot then rapidly cooling with Co2 or extremely cold air cause micro fractures in your barrel of receivers? Just thought I would ask. I know you can take red hot steel and dunk in cold water to make it stronger. Just wondering if that constant expanding then sudden contraction of barrels n receivers cause structural issues??