A new gadget for the colony varmint shooter, a battery powered fan that the manufacturer claims will cool a barrel down in as little as 7 minutes.

www.megnetospeed.com

260Remguy: I think I found a much more direct link to the item you are referring to.

Link: https://ads.midwayusa.com/product/624248/magnetospeed-riflekuhl-barrel-cooler

Looks interesting thanks for the heads up.
I have a similar fan that runs on batteries that I use to stand up next to Rifles I am testing and I point it down the barrel from just at the Rifles action - it pushes heat waves away from my barrel/scope picture.
On rare occasions when my barrels do get hot in the field I can direct the air flow from my fan into the Rifles chamber and down the barrel - the Magneto device, I am sure, would be much more efficient at cooling the barrel.
Neat idea to direct that moving air down the barrel from the chamber.
Thanks for the heads up.
Hold into the wind
VarmintGuy

Here's a similar one.

https://www.chamberchiller.com

my deceased hunting partner came up with the compressed air bottles with adapter hose to insert at the chamber, would cool barrel in about 5 minutes, he used this at his range, kept a bottle under the 300yd bench, we had bench's out to 500yds.

Freon spray cans, get at electronics supply. Or probably Amazon. (they have everything)

HM