Best guage and bullet weight for long range

[BillB204]

Best caliber and bullet weight for long range

I'm moving toward long range (600 - 1000 yards) shooting/competition. Limited budget ($1500 gun and glass). I have questions that I've been researching and have gotten 100's of opinions.

Caliber - There aren't too many who disagree that the .308 is in the top 2-3 and most believe that it is #1. But I've also heard that the 7mmRM and the 6.5BR is edging out the .308. The argument is they have flatter trajectories. According to my research, the 7mm does have a slightly flatter trajectory with an equal weight bullet (175), but the 6.5 is much less flat even with a lighter bullet (140). So does flatter trajectory necessarily equal better 1k accuracy? And which of these (or other common guages) would be best for long range? I have a 243wssm that has an extremely flat trajectory and is a tacker. But the heaviest bullet I can shoot is 100gr. I'm afraid even a slight breeze at 1k will make it a joke.

Bullet - According to my research, it seems the longer the bullet, the higher the BC. I suppose the plus is that the heavier weight resists environmental factors better, but the con is that there is more bullet drop. Does BC necessarily equal better accuracy? And what is the preferred bullet weight for 1k for 308, 7mm, 6.5?

Scope - (maybe a no-brainer) I've never shot at 1000 yards. But at 200-300 yards, the bigger the target looks through glass, the better groups I get. It would seem that a 32x would be best for 1k. Assuming I can get almost the same clarity from a 32x as a 24x, would the 32x (or even a 40x) be better for 1k. What powers do most competition shooters use for 1k?

Thanks a lot.

 

[jmorris]

.30 caliber has won more overall but that means very little. No, flatter trajectory or better BC doesn’t = more accuracy.

Take a look at these links they give a decent overview.

http://www.6mmbr.com/1000ydpg01.html

http://www.6mmbr.com/1000ydpg02.html

 

[Jim Watson]

Guage?
Uh, sorry to get into clip vs magazine mode, but we use rifles for long range target shooting and call them by caliber and cartridge.

What kind of competition do you envision? There are rules.

Trajectory does not matter at known range shooting. You set your sights for the target. What higher velocity and ballistic coefficient get you is reduced wind deflection.

You might see better short range or calm air accuracy with a lower BC bullet that happened to suit your barrel, but it would not deliver as good accuracy at longer ranges in the wind.

Optimum bullet weight depends on caliber and cartridge. The usual thing for a .308 is 175 gr unless you are a Palma shooter driving a 155 at the highest velocity you can get with a long barrel and heavy loads. A .30-06 or .300 Magnum would benefit from 190-240 gr bullets.

Why not take your .243 WSSM out at 600 yards?
You could learn a lot with much lower startup costs.
By the time you have shot out that barrel, you would be ready for a new barrel or a new rifle optimized for whatever version of the sport you liked.

 

[BillB204]

Good tips Jim. Brain fart on the "guage" language. That's what I get when I write on the run. And I do like your idea of taking the 243 out as far as I can to see how far out I can get before really losing grouping. I just ass-umed that at 600 yards a 95-100 gr bullet wouldn't be able to hold. But at 3300-3400 fps, I won't know until I try.

For 1k, would your preference be 308 or 7mmRM? How heavy a bullet would you shoot in the 7mm?

Thanks.

 

[Jim Watson]

My only serious long range shooting is NRA F-T/R which is limited to .223 or .308.
Shooting .223 at 1000 yards is a challenge. (But it is fine at 600.)
I have shot both 155 gr Scenars and 175 gr Sierras in .308. The Scenar has a theoretical advantage with a BC as high as the SMK and a higher velocity. I guess I am just not a good enough shot to tell much difference.
If I were shooting a 7mm, it looks like the 175 - 180 gr bullets are the leaders.