Too cold for working up hunting loads?
- Thread starter Joel
- Start date
Right.
That makes sense.
Although tbh, i have never paid attention to that either.
I live and hunt coastal. Not much in the way of temp swings.
I also occasionally hunt interior in colder weather. No issues.
But i spose i have never worked up a load in colder coastal climes that I then used in hotter interior climes so I concede i dont know much about that at all.
If you are using Hodgdon's extreme line of powders, the new temp stable Alliant powders, and a few of the other more temperature insensitive powders, I wouldn't worry too much about it. Just don't be pushing it right to max load or over, because then you might run i to some issues when it warms up.
If you are planning on using some powders that are known to have wide fluctuations of burn rate, depending on the temperature of the round, I would definitely reconsider. But that also depends on how cold you are talking, and how warm if weather you will be shooting them in.
I have worked up loads a bit below zero, that shot perfectly in the summer time, with very minimal change. But I was also using H4350, Varget, and H4895. Which are very temp stable powders, depending on the exact cartridge they are shot in, but across the board, pretty stable.
My 300RUM loads with 225-240 grain bullets use 101.0 grains of US869, I worked up in the heat, because it changes quite a bit. Shoots almost exact same point of impact 40°C and -40°C. I do not load for groups at that temp, but I will take a quick measurement of speed and point of impact when I'm going out for elk, regardless of how cold it is outside. Once it gets cold enough, and your bore diameter decreases in size, you will start to gain some speed again, and build more pressure.
And for some reason every bullet over 220 grain just plain likes 101.0 grains of powder. I get a few hundred fps drop in velocity, so only same POI at a hundred yards. And I works great for hunting, and easy to load for.
I would recommend developing the load in the hotter months, then checking poi and velocity in the cooler ones. You can for hunting, just to develop the load around the temperature it normally is around hunting season, and use that load for hunting season. All the ways work, just pay attention to what max load is, and try to get info on the temp stability of the powder you are using.
If you are planning on using some powders that are known to have wide fluctuations of burn rate, depending on the temperature of the round, I would definitely reconsider. But that also depends on how cold you are talking, and how warm if weather you will be shooting them in.
I have worked up loads a bit below zero, that shot perfectly in the summer time, with very minimal change. But I was also using H4350, Varget, and H4895. Which are very temp stable powders, depending on the exact cartridge they are shot in, but across the board, pretty stable.
My 300RUM loads with 225-240 grain bullets use 101.0 grains of US869, I worked up in the heat, because it changes quite a bit. Shoots almost exact same point of impact 40°C and -40°C. I do not load for groups at that temp, but I will take a quick measurement of speed and point of impact when I'm going out for elk, regardless of how cold it is outside. Once it gets cold enough, and your bore diameter decreases in size, you will start to gain some speed again, and build more pressure.
And for some reason every bullet over 220 grain just plain likes 101.0 grains of powder. I get a few hundred fps drop in velocity, so only same POI at a hundred yards. And I works great for hunting, and easy to load for.
I would recommend developing the load in the hotter months, then checking poi and velocity in the cooler ones. You can for hunting, just to develop the load around the temperature it normally is around hunting season, and use that load for hunting season. All the ways work, just pay attention to what max load is, and try to get info on the temp stability of the powder you are using.
I know 40 below is a waste of time. 30 isn’t great, but around -20 things are looking up at least with fairly temperature stable powders..
It’s not just gaining pressure, what happens to velocity at -40 will depress you. On the otherhand if you have no choice or nothing else to do go for it. I normally load up pressure signs then back off a grain in the summer and 2 in the winter on magnum sized cases. If you’re a back off 2 kind of guy, then back off 3. Consider that a “for now” maximum and load accordingly.
For the last 5 years my loading bench has been 35 feet from a shooting bench and only 5 feet of that is outside so its easy to keep rifles and ammo at room temperature. The target doesn’t care how cold it is.
It’s not just gaining pressure, what happens to velocity at -40 will depress you. On the otherhand if you have no choice or nothing else to do go for it. I normally load up pressure signs then back off a grain in the summer and 2 in the winter on magnum sized cases. If you’re a back off 2 kind of guy, then back off 3. Consider that a “for now” maximum and load accordingly.
For the last 5 years my loading bench has been 35 feet from a shooting bench and only 5 feet of that is outside so its easy to keep rifles and ammo at room temperature. The target doesn’t care how cold it is.
I was just wondering about this.
Made a bunch of loads recently as moving to new powder stash and almost all were quite a bit slower than I expected which got me wondering if the 0 degrees C temps were a factor.
I have also wondered if it could result in excess pressure in the summer with the potential 40 degrees C ish temp increase
Made a bunch of loads recently as moving to new powder stash and almost all were quite a bit slower than I expected which got me wondering if the 0 degrees C temps were a factor.
I have also wondered if it could result in excess pressure in the summer with the potential 40 degrees C ish temp increase
I bulk load on a Dillon 550 and any cartridge in the 30-60 grain powder range gets automatically reduced 1.5g off max. Thats my fudge factor for a progressive machine and a bit of a buffer for summer to winter pressure changes/surprises. When you live on the top edge of pressure bolt lift increases and brass life decreases. It’s a misconception that best accuracy lives at maximum velocity.
I've always done my load development / testing in the spring. The odd time, a little bit during summer(don't like the heat) ! Moreso, I always did a fair bit more in the early fall. Cooler, with the fall smells, suns not heating my ammo up to extremes and, as a plus, it's prior to my deer hunting season...lol
All of my load development takes-place in the winter, it will be the closest to hunting tempertures in November.
I pick and choose the days to shoot that are ideal, the right temperature and low wind. Usually my loads are complete and just waiting for the right day. Being retired makes it easier.
I usually don't concern myself with powder that is sensitive to temperatures, only powders that the rifle loves. (accuracy and velocity)
I pick and choose the days to shoot that are ideal, the right temperature and low wind. Usually my loads are complete and just waiting for the right day. Being retired makes it easier.
I usually don't concern myself with powder that is sensitive to temperatures, only powders that the rifle loves. (accuracy and velocity)
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- Location
- Saskatoon Saskatchewan
The garmin and similar chronographs pretty much get rid of the need to worry about temp swings. If you take good notes and know what your velocity will approximately be at different temps, its easy to change your dope with the temp. Ive never noticed that a load i worked up in the summer shot poorly in the winter but I have lost some fps.
If your worried about ammo being cold at the range, you can use those chemical hand warmers in a small cooler with your ammo and try to shoot your groups before they cool off. You can do the same in the summer with ice packs. An infrared thermometer would help with this to see what your actual ammo temp is.
If your worried about ammo being cold at the range, you can use those chemical hand warmers in a small cooler with your ammo and try to shoot your groups before they cool off. You can do the same in the summer with ice packs. An infrared thermometer would help with this to see what your actual ammo temp is.
I do down to -10c especially if it will be use for winter hunting like bison for instance. Then I don’t want to develop a load in July to be used in January where they can be 60 degrees difference! Most of my développement is done in the spring summer and fall but never at the extremes temperature wise, so not in July mid afternoon when it’s 25c and not in -25c either and that’s mainly cause it sucks to shoot in those temperatures lol.
So ideally I develop loads in temps similar to what I will be hunting in.
So ideally I develop loads in temps similar to what I will be hunting in.
I'm doing it right now. I put my loads in a small cooler and add a couple of bean bags, the kind you heat up for sore muscles. Put a few foulers through the barrel to warm it up and then shoot. I know it's not perfect, but my rounds are warm (not hot) so I pretty close to what they would be on a summer day.
Keep 10-20 rounds in the inside pocket of your coat. Keep the rest in your warm vehicle.
- Location
- Saskatchewan
I find myself shooting in very warm weather more than I do in extreme cold any more. So I make sure loads are safe at the warmest temperatures I may encounter. The loads I've developed in recent years have often been for more exotic big game cartridges that I've used on safari in Africa. Temperatures there can be very similar to our summers. So while I have done some cold weather load development, I always check and fine tune in temperatures close to what the hunt will be. An African hunt requires too much time, money, and commitment to take any shortcuts.
I shoot mostly in winter as is the quiet time at the range. Try and do load development in the 0 to -5c ranges as other have said is hunting weather. Hot days I've noticed some velocity spikes with these loads but nothing crazy. using imr 4198 4895 4064 powders mostly.
