Calvin45
Well-Known Member
Hi all, as some of you know I've had an itch for a while to test loads in true extreme cold (-40 c - around that point Fahrenheit and celcius are the same, -40 either way). It does usually get that cold a few times per winter where I live in Saskatchewan, but anything below -30 celcius will do. Just never have time
On the right day.
Anyways….I've had another theoretical musing to run by you, and this to do with "overstabalization". I know that's a contentious word, but I also know it's a real problem in my experience. Varmint bullets 6.5mm and under seem to do fine accuracy wise even at ungodly high rpms, but larger bores struggle more. I got a load for my .300 win mag pushing a 120 Barnes tac tx (orig a 300 blk bullet) at 4050 fps. It's minute of whitetail accurate to 400 yards as I found last November with two successful hunts. But it never realized particularly good accuracy compared to heavier slugs moving slower. Rifle is a 10 twist. After fiddling with other variables I realized that the forum members here were right: it was simply spinning way too hard for full accuracy potential to be realized, or "overstable".
NOW: it's well known that you need more stability a) at lower elevation and b) at lower temperatures SO……do y'all think the groups might tighten up with an excessively fast-for-projectile twist rate at crazy high velocity when shooting in extreme cold, because the bullet will be comparatively less over-stabilized that it was in July during load work up???? Never had this thought till today.
On the right day.
Anyways….I've had another theoretical musing to run by you, and this to do with "overstabalization". I know that's a contentious word, but I also know it's a real problem in my experience. Varmint bullets 6.5mm and under seem to do fine accuracy wise even at ungodly high rpms, but larger bores struggle more. I got a load for my .300 win mag pushing a 120 Barnes tac tx (orig a 300 blk bullet) at 4050 fps. It's minute of whitetail accurate to 400 yards as I found last November with two successful hunts. But it never realized particularly good accuracy compared to heavier slugs moving slower. Rifle is a 10 twist. After fiddling with other variables I realized that the forum members here were right: it was simply spinning way too hard for full accuracy potential to be realized, or "overstable".
NOW: it's well known that you need more stability a) at lower elevation and b) at lower temperatures SO……do y'all think the groups might tighten up with an excessively fast-for-projectile twist rate at crazy high velocity when shooting in extreme cold, because the bullet will be comparatively less over-stabilized that it was in July during load work up???? Never had this thought till today.
