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Bare with me for a second concerning cold bore shots. I know this question may sound absurd or TOS-ish but is there a specific range of temp that a "cold bore" is? I know many first shots are critical be it hunting or killing/man stopping. Is there an accepted way of practicing this at the range? Shoot one round and let it cool for how long?
The_Hammer_Man
12-11-12, 14:58
Cold bore shot is:
Dirty barrel (at least one round fired.. I do 2)
Barrel temp at ambient. (ie, same temp as the air. 65F air/65F barrel)
I use a digital strip thermometer.
The "cold shooter" is usually the biggest factor to the "cold bore" shot...
........I use a digital strip thermometer.
Thanks for the tip. I can put the regular thermometer back in the medicine chest.
Bare with me for a second concerning cold bore shots. I know this question may sound absurd or TOS-ish but is there a specific range of temp that a "cold bore" is? I know many first shots are critical be it hunting or killing/man stopping. Is there an accepted way of practicing this at the range? Shoot one round and let it cool for how long?
Interesting question. A few years ago I attended a Tactical Rifle Match, where the first shot of the day was at an 8" steel plate at 600 yds (known distance) to be shot prone off your bipod or pack. Only one shot allowed, no sighters. Temp was about 35 degrees, wind quartering at about 6 mph.
Anyway, we had 24 shooters, and 23 misses. And yes, I missed too...:no:
How many of you hit low? Really no way to tell. Just a steel plate hanging from a frame via a chain and the backstop was nothing but dense woods and a gentle up-hill slope. But if I had to guess, most of us missed low.
How many of you hit low?
Excellent question. That was my first thought.
Carlos Hathcock taught cold bore shooting by having the student fire one single shot and recording the result and the range conditions. One shot and one shot only for that day. One shooter related how he didn't understand why until he realized he was collecting data on how he and his rifle performed for that single, often critical shot
How many of you hit low?
Depends on the rifle for me. I have a .243 bolt gun that's consistently ~1.5 MOA high on the first shot of the day, and a SCAR H that's just about the exact opposite.
In the long range world its most often referred to as the "clean cold bore" shot, not just the cold bore shot. In the traditional sense of military sniping that is the shot that counts. Same could be said for hunting at long ranges in some cases although you don't have to worry about it being a two way range and the game may stick around for a second shot in some cases. Some barrels might shoot better with a fouling round or two but as mentioned that would be a cold bore shot. If a barrel is match quality/broken in and the rifle is top notch it should put that first shot the same place as the second. Not sure how good the semi's are at that though.
Thanks for the feedback thus far. I'm going to keep my eye on this thread. :cool:
davidjinks
12-13-12, 07:10
I know this question was intended for a different poster...
However, both of my MK12ish rifles shoot low left on cold bore shots. I'd say ~1.5" @ 100 yards. Both rifles are consistent with each other and both are setup slightly different than each (Rails, scopes and muzzle devices). Both barrels are Douglas SPR barrels.
My Ruger M77 270 Win shoots way high on cold bore shots. Something I failed to take into consideration this last deer hunt. I did get my deer but no tender loins...
How many of you hit low?
I stopped getting meaningful variances in "cold bore" shots when I stopped cleaning the piss out of my barrels. After I've cleaned, I may get a difference in "CCB", small, though, and if I have to strip copper, all bets are off. Maybe I'm lucky.
I have seen, however, many, many guys hit low in the cold--not because they didn't plug it into their calculators, but because they were using a chrono velocity they got from their ammo at 70 or 80 degrees. Modern "temp stable" powders are better than what it used to be, but you can still lose enough velocity to drop you right off a target that small.
Doc. Holiday
12-13-12, 10:26
I learned a lot by watching Magpul's Precision Gun DVD. When I was new with long range stuff (Hell...I still am new to it) I watched a lot of it and it gave me some good knowledge and a great starting point. There's a lot of little tips that were in it that I really like. Cold bore vs Clean bore was one of them. (You can actually youtube that part on the DVD)
BravoHotel
12-13-12, 15:36
I have seen, however, many, many guys hit low in the cold--not because they didn't plug it into their calculators, but because they were using a chrono velocity they got from their ammo at 70 or 80 degrees. Modern "temp stable" powders are better than what it used to be, but you can still lose enough velocity to drop you right off a target that small.
That's definitely something one needs to take into consideration. I need to get my hands on a chrono and do some cold temp testing to see how much my velocity drops.
Thanks!
I learned a lot by watching Magpul's Precision Gun DVD. When I was new with long range stuff (Hell...I still am new to it) I watched a lot of it and it gave me some good knowledge and a great starting point. There's a lot of little tips that were in it that I really like. Cold bore vs Clean bore was one of them. (You can actually youtube that part on the DVD)
I googled and came up with this video. Very informative, i learned alot....
http://www.youtube.com/watch?v=qgyvdX0-7VU
Worth looking here too:
http://youtu.be/ewPWplWu6ZQ
USAMU video with good example.
Doc. Holiday
12-14-12, 08:49
I googled and came up with this video. Very informative, i learned alot....
http://www.youtube.com/watch?v=qgyvdX0-7VU
Yup that's the one!
Doc. Holiday
12-14-12, 08:50
There is another part of the DVD that is on youtube that shows the magpul guys shooting all at a mile and Travis Haley is able to nail a target at a mile with a .308. Took him a few tries, but it was pretty cool to see.
*Nearly* everyone can hit a target at a mile with a .308, given a rig with enough elevation that stays stable through the transonic-subsonic transition, some fundamentals, a bit of ammo, stable wind conditions, and a good spotter.
Not entirely practical, NOT a high percentage shot by ANY means, but absolutely possible. Demonstrates what can be done if you really, really had to take a poke for some reason, but more of a confidence builder than anything.
Caylen is currently taking guys out to 1200 or 1300 in the 4-day PR1 with .308s and no prior training to get them through transonic, but going to a mile with a .308 for everyone isn't really worth the squeeze IMHO, since there's not much additional learning involved, and if there's any variability with the wind, you could do everything right and still chase the target all day.
*warning: shameless plug...
Come on out to a PR class with Caylen...He's got a great program, and you will definitely take something away from it, no matter where your experience level is.
Doc. Holiday
12-14-12, 11:29
I just liked it to show some guys that say the 308 round is only effective at 700 meters. I agree that their are many better options out there to shoot at long distances, but I laugh when guys say it's a waste of time to shoot the 308 past 700 meters. I think the 308 is great till 1100 yards. Again, I know there are better rounds out there that will do it more accurately, but those rounds also cost much more than 308 rounds.
I'll second the rec for a class with Caylen/Magpul, I had a class with him before he joined up with Magpul and he's a great guy and a great teacher.
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