barrel cooling time- temp during load development

[Willoughby]

what barrel cooling time- temp is acceptable to prevent throat erosion during load development
I have limited range time & need to make the most of it without damaging my barrels
barrel changing is not a problem - I use Savage prefits mostly
I don't expect a barrel to last forever -but neither do I wish to waste one

any helpful response's greatly appreciated
thanks in advance

 

[GSPV]

I think that you're over thinking it. Just don't rapid fire and clean it at reasonable intervals and you'll be fine.

A bigger question might be what kind of shooting that you're developing for. If you're developing for a cold-bore kind of shot...one shot from a barrel at ambient temperature...it might impact how much you let it cool, especially later in the process.

 

[spclark]

My shooting disciplines allow one round a minute, sometimes more. Consequently I try to keep at least 30 seconds between test rounds (assuming a five-shot string) when load testing. I'm not looking for groups so much as vertical displacement so wind isn't as significant a factor at these sessions.

 

[gotcha]

I only judge Temp. by touch. If the chamber area is too hot to hold my palm against without yelling YOOUCH! its time to cool a bit, until I can hold the chamber & the area about 1/2 to 2/3 way down the barrel comfortably. The higher the ambient the quicker the heating. Ditto for amount of powder charge. Some folks use a can of compressed air which, through its rapid expansion, becomes cooler & blow into the chamber. I've seen others that use homemade fans to direct air. Some going as far as creating a hose to place in the chamber forcing cooling air through the entire bore. If my range time was as limited as yours I'd give some thought to a forced air device of sorts. And shoot/cool in the shade if at all possible.

 

[bobm]

I shoot high power rifle silhouette with the 7-08 cartridge. A year ago another shooter was concerned about how hot his barrel was getting during the relays. Curious, I attached a temperature probe to my barrel three inches ahead of the chamber. The plug end went into a Fluke thermometer. Ambient start temp was 90 degrees. After a 5 shot in two minute relay the temp reached 127 degrees. The second 5 shot relay peaked at 143 degrees. The third and final five shot relay just maintained 143 to 145 degrees F. In all 15 shots were fired in about ten minutes time. The peak temp only reached 145 degrees....far below the melting temp of barrel steel. It returned to the ambient 90 degrees in about ten minutes. The load used 38 grains of Varget pushing a 150 SMK.

It is true that every shot fired will wash out some steel. My stainless match barrels will last and shoot very well for an average of 6500-7000 shots.

 

[lpreddick]

at one time radio shack sold a digital temp device that had a probe leading to the screen of the sensor. i velcroed the probe about 3-4 in in front of the chamber and would shoot until a chosen temp appeared (for ex. 12 shots) then wait until it dropped to a chosen temp, then resumed shooting using the low and high temps as my range. more shots in cold weather, less in summer. when hot i would soak a small towel and lay on barrel, watching the temp fall until reaching the low point. having more than one gun also allows you to continue having fun.