Barrels & temps.

[kenbrofox]

Hi, are there any technos out there who can tell me wether a rifle barrel is designed to shoot best when cold or is there an optimum temperature? Also does the ambient temp. in some of your hotter states have a detrimental effect on barrel performance? Thanks KB.

[Rick in Oregon]

Ken: I can't back this up with a techno link, but it's always been my thought that a barrel will shoot best if not too hot or not too cold, and that could be somewhere around 70*F. We all know not to shoot a too hot of a barrel due to potential throat erosion, and a too cold barrel will actually contract with the cold and narrow the bore somwhat, metal being subjective to thermal contraction.

Also, in very cold weather, the powder temp burns cooler, the air is denser, and thereby most always velocities will always be much lower in cold temperature environments.

We shoot coyotes here in the winter months, sometimes the temp hovers around zero farenhiet, but we also send thousands of rounds downrange in the spring for squirrels, and in the summer months for both squirrels and prairie dogs. The temps on those shoots can and do approach 100*F, so one must really be aware of overheating the barrel, less we go home with smoothbores.

This is one of the primary reasons my crew and I take time out to clean in the field, as it removes the carbon and copper fouling, and gives the barrel a chance to cool to ambient temperature. Between shots from the bench we leave our bolts open to allow air circulation, and it all really makes a difference.

Hope this helps a tad.

[kenbrofox]

Hi Rick, Thats all interesting information. I was wondering if barrels might have been made tapering from muzzle to breech so that they would change to a true cylinder when the breech warmed up(assuming the action end operates at higher temps. than the other end) as i was told by a Canadian pilot that the cylinders on his aircraft tapered towards the hot end until it arrived at it's operating temp. Must stop.......Beginning to sound insane, even to meself.KB.

[Rick in Oregon]

Ken: Interesting theory, but in fact when barrels are made, the maker takes great pains to ensure complete uniformity from breach to muzzle, and are even air gauged to ensure tolerances in the .0001" range, the closer to perfect uniformity, the better.

Best to leave aircraft engine thermodynamics to the aeronautical enginers me thinks, as there's not much crossover to interior ballistics, although many principals and laws of physics apply to both.

Too much time on your hands today, buddy? Get a cup of tea and retire to your gun room and find something to reload.

[kenbrofox]

Yeah alright, you're right Rick but i think it will have to be a mug of redeye ,not tea.KB.

[Rick in Oregon]

Ha! Gotcha! Works for me too Ken. They're giving me stuff here in the "White Hotel" even stronger than any favorite beverage at home, that's fer sure! Right now I should not be allowed to be within 25' of my reloading bench!

[kenbrofox]

Could do with some whiskey like that...get the reqired result but still have your faculties in good working order.( as you obviously have) youcould make a fortune.

[Arizona Hunter]

This thread is way over my head; physics, thermodynamics, sturctural integrity....-I'm just a simple salesman.

For me I just go shooting when I have the opportunity-hot or cold ambient temp. If there is a prairie dog in the scope all the better!
If my barrel gets too hot I slow the pace or eat a sandwhich. Although now I have a second 204!!!! for when the first one gets too hot.

[Rick in Oregon]

AZ Hunter: You're right....I was in the hospital on strong pain meds during that post....what was I thinking? It was their fault for letting me near a computer terminal.....

It's not rocket science: if barrel too hot, stop shooting until cooler. But you hit the proverbial nail on the head.....two rifles better than one, and three better than two! Works for me.

[cracker]

O.K. to change the subject just a little. If I am shooting and my barrel gets warm not really hot at this point can I put a cold wet towel over it to help it cool. I am one that don't like going from hot to cold with expansion and contration going on. I have heard of people doing this but it just sounds like the wrong thing to do. Also if this shouldn't be done its more reasons for more guns
Sportingly
Cracker

[Rick in Oregon]

cracker: We use the wet white towel method often when barrels get a bit warm on a hot day in the squirrel patch. I soak mine with water from melted ice in my ice chest and lay it over my barrel while cleaning. This works best of course with stainless steel barrels. Some guys use gallon milk jugs filled with water, with a piece of 1/4" clear plastic aquarium tubing stuck into the jug lid, and pour the water down their barrels from the breach end. I've also seen guys use CO2 bottles with the same tubing to cool hot barrels. I'm a bit wary of cooling too quickly though, and have never used the CO2 method.

One of our Eastern Oregon Raptor Feeding Society members, Rat Force One (Dan, Captqc's son) made a neat device for shading and cooling his barrel from a car windshield sun reflector. It seems to work quite well, no water required, and it does a decent job of cooling his barrels while cleaning in the field getting ready for the next onslaught of fire downrange.

His shooting position with the barrel shade can be seen as the third one from the right:



Here's another shot that shows it a bit better:



That's Dan glassing targets (in the white t-shirt on the right) that his dad, Gary at the far end is engaging with his 204. My Sako M75 Varmint 204 is in the foreground atop my bench, and Garth is on the far side of my bench drawing down on Skippy with his M700 VLS in .223. Sitting on top of the flatbed trailers giving an elevated shooting position was really the hot setup, and really enabled us to stretch out the range. By sheer coincidence, all the rifle stocks on our benches at that particular time were all laminated.....it looked pretty cool seeing them all lined up.

When in a target rich environment with barrels getting hot from the great shooting, I want to have an accurate rifle, and to keep it at its peak accuracy level, cooling and cleaning are mandatory. I'm not sure our methods are the best, but they seem to work for us when either in a prairie dog field, or a great ground squirrel alfalfa patch. Skippy however, wishes we'd just let our barrels melt!

[Arizona Hunter]

Oh, man those flatbeds are super cooool! All you need is a large umbrella! My friend sets up a 7' tall umbrella and attaches it somehow to his chair when he shoots. I've asked him to make me one but so far I'm still sitting in the sun.

[Rick in Oregon]

AZ Hunter: Normally we use the Quik Shades for shooting out in the hot sun, but they would not work on the trailers; too wide of a footprint. Forget attaching the umbrella to your bench....been there, does not work. Every little breeze affects the umbrella, and moves your sight picture around and spoils any precision shooting. Just not a good idea at all.

This is the setup we use, and the shade is not affected by the wind in regard to sight picture. Remember when using any shade device, be careful of the wind if it gets fiesty. We spike our shades down, but if the wind gets to 20 mph.....time to put it back in the truck, lest it get blown into the next zip code.



Wally World sells the shades shown, a good deal for not getting sun-fried. It also helps keep your barrel cooler than sitting out in the hot sun all day.

[Lenard]

Hey Rick, it appears to me that the trailer you guys are pulling, probably gets filled up with all the gear you have on a shoot. That is fun though.

The first time I went to shoot rats around '90, my old friend and I sat under a couple juniper trees and shot off our benches from 9:00- 3:00. We had our coolers with drinks and food and hardly got up all day. It also was the first time either of us had shot a rat at 200 yards. Been hooked ever since. Haven't missed a year of shooting them either.

Lenard

[Rick in Oregon]

Lenard: All the gear has been an evolution of sorts, as I got started shooting rats seriously right after I returned to "The World" in 1967 with my pet Sako 222 Rem Mag, and been doing it ever since. It has morphed from just a rifle and bino's with a fanny pack to "all day in one spot" field shooting with more gear and neat gadgets. I still get out without all the gear and just do a walkabout with a bipod, but the cameradire bench shooting all day with friends is quite a bit of fun seeing just how far we can connect on Skippy.

As for range, there's nothing quite like connecting on a sage rat past the 500 yard marker, as they are about half the size of an adult prairie dog as you well know. After many seasons shooting our rats, hitting PD's at the 500 yd. mark seemed easy. Now a chucks head peeking over his rock with the wind blowing is another matter altogether. It's all good!