Road_Clam said:
A .308 will get you to 1k but I recommend a min 24" bbl, 26" even better . You will need a 168- 175 gr bullet traveling at about a minimum 2600 fps to avoid possibly going transonic. When I shot 1k at Sig a few shooters were under barreled and shot good till about 750 yds. At 1k a few of the 18 and 20" "tatical" bbl guys were going transonic and getting unpredictable accuracy.
Even with a 24-26" barrel there are no guarantees you'll stay supersonic at 1000 with the bullets you mentioned. At sea level your subsonic by 900 yards with the speed you listed and the bullet weights. Move to 4000 ft ASL and you're supersonic past 1000 yards with the .308 from even the 20" barrel. However just because your bullet goes transonic before 1000 yards doesn't mean the shot can't be accurate, as some bullet designs handle the transition from super to subsonic better than others.
agtman said:
L.R. rookies, no doubt.
A 20" tube might be *okay* to 800yds max, but the velocity lost contributes to imprecision, notwithstanding other shooter-induced errors, and your shot-groups will open up markedly compared, say, to what you shot back at 500yds (the old-school rifleman's quarter mile).
The longer tube allows you to keep your placement tighter the farther out you go. That level of precision is what the L.R. honchos mean when they talk about "aim small, miss small."
That said, ... there are a lot of "Sunday afternoon snipers" - guy only looking to shoot, maybe, 20-30 rounds off the bench at the club - who don't care about these sorts of details.
Velocity loss has nothing to do with how much precision a rifle is capable of. Often times you don't even
lose 20 fps per inch of difference between 20-26" barrels. Velocity does help with wind as it shortens the time of flight to target giving wind less time to act upon the bullet. So if there is around 100 fps difference at the muzzle between a 20" vs. 26" you have a TOF difference at 1000 yards of .084 seconds and a difference 1 MOA value of windage.
Longer barrels don't allow bullets groups to be any tighter. The only time it might is when using aperture sights, where a longer sight radius helps with precision. When it comes down to using optics often times the
shorter barrel proves to be the more accurate barrel.
How much more accurate is a $3000-5000 custom with a .5 MOA guarantee going to be at 1000 yards vs. a sub $1000 Tikka with a MOA guarantee? On average it'll be about 4% more accurate if all things else are equal. This is according to
Precision Rifle Blog and the Brian Litz designed "Weapon Employment Zone" (WEZ) analisys tool. Now and extra 4% can mean a lot in organized competition, but it isn't worth the money until you're competing.
kcub said:
Yes a .243 Win could definitely work. However, there are some issues as there isn't a factory rifle produced yet with the proper twist to run good long range bullets 100% of the time. Where I live the factory Remington and Savage 1:9 twist barrels will generally allow you to shoot the 105 grain A-Max and BTHP from Hornady year around. However, when you get to sea level and cold fall and winter temperatures that increase atmospheric density you could very well run into problems where the Hornady bullets won't stabilize.
If you want to do a LR .243 your rifle needs a 1:8 or faster twist to take advantage of quality LR bullets made for the 6mm/.243 caliber rifles. Some other good LR 6mm cartridges are the 6XC, 6mm Dasher, 6mm Creedmoor, 6mm SLR, 6mm BR, and 6mm Competition Match, all of which are supposed to give you longer barrel life vs. the .243 Win. Though none of these fit into the OP wanting a factory ammunition option except the .243, which has very limited factory loads with good long range bullets.
And that's why GAPs command premium prices, why the wait-times are so long, and why they get snatched up so fast when they're available - new or used!
