Some report more reliable ignition in the winter with larger casings using magnum primers. One member stated his summer load worked out identical accross the chrony in the winter by just switching to magnum primers. I have not tested this theory. And if it works, it might only be in certain chamberings/powder/bullet weight combos.
What distances do you expect to use the 284 at, and what size groups are acceptable to you? If you need minute of coyote at 300 yards it migh not be as critical as say minute of fox at 600 yards. I would find a load that uses powder filling 90%+ of the brass and magnum primers and go from there if it was me. Then come warmer weather, either use a totally new worked up load in a different powder/primer, or just reduce and rework it up from a grain or two less. The latter would be the most economical, and theoretically should still remain as accurate as at -20.
I have never worried about "temperature sensitive" powders until I read about them on the net. However since I was unaware I wasn't looking for it either, poor grouping was blamed on colder barrel, uneven barrel temps, denser air, or whatever, possibly my own shivering! I can't say for sure if the temperature sensitive issue is as drastic as some would have us believe or not, I am just not experienced enough testing it, and have not seen anything to prove or disprove it yet. I do however know that some of my loads are much slower when the mercury drops compared to hot days. Most say IMR powder is more temp sensitive... could be. Your own testing will answer that for you just fine I bet!
I am sure someone with more definite answers will chiime in and help, I don't have much more to offer, not that it was much to begin with! lol
.
Me thinks you don't give yourself enough credit, my friend!
To
ME, changing "mechanical" variables such as powder or primer, is classified as waste. At least, for my intents and purposes. What I would like to see is this; a load that shoots well now, that may take some final tweaking in warmer weather to shoot really well. After all Cleftwynd, not everybody is privvy to a heated shooting shack!
I won't be using my .284 as a coyote rifle unless the situation conveniently presents itself. I have other rifles for that when used deliberately. This is my first venture into precision rifle type stuff. I have tried many years to get factory rifles to shoot like precision rigs with varying results - some fantastic, some disgusting. I intend to use this thing to get accurately to 1000 yards and possibly beyond, to attempt to develop skills I have dreamt about since I was a kid and
knowing that my rifle is not the likely culprit when I fail. As far as numbers go, I've talked to several guys that say if you have a rifle that shows you 1 MOA, it'll do well at the 1k mark. Honestly, if I could hit a sheet of plywood consistantly at that range, I'd be excited. Well, not quite, but it would sure do a lot for my confidence in my equipment and ability.
At closer ranges (that I'm very used to) I have a 5/8" group at 264 yards with a factory rifle that I would
LOVE to beat! If I do, I think I'll just quit. Uh......nah!
My 30-06 loads were developed in august and I cant shoot them in the winter. Flat primers, cracked brass, and am getting 100-150 fps more then in the fall.
Wow! How the heck is this possible? That kinda goes against
everything I've read or experienced. That seems goofy as this dang
but there has to be some logical explanation, no? Maybe you're shooting a chinese surplus female rifle? Just kidding buddy. Ooooh, I gotta remember; engage brain, then mouth....
Work up your loads in the winter, final test is heat them up on truck vent and shoot . Will give you an idea on summer "issues".
Ya know, I never thought of that. But it would seem that this may have some validity, providing one could maintain the elevated temperature of the cartridges through to detonation. Sounds like a Mythbusters type of project. Perhaps for someone with a fancy heated shooting shack?!?!
Okay, I'm done
