Re: 264 Win Mag for long range?
Are you going to shoot it a lot? If so, there are better choices that deliver almost as much usable performance at far less cost and aggravation. If not, get out your wallet and have at it...
I have a .260, a 6.5-284 on it's second barrel, a new 6.5-284 and a 6.5-300 Weatherby, so, while I don't have a .264 WinMag, I have played with a few 6.5s...
The single biggest problem with the .264 is barrel life vs the <span style="text-decoration: underline">ACTUAL</span> velocity return. Despite the hype, loaded to safe pressures, it's probably a 3,050 to 3,150 fps cartridge in customary barrel lengths. We can quickly get beyond the point of diminishing returns, and the .264 is already there. Ever wonder why <span style="text-decoration: underline">everyone</span> shoots a .264 and raves about it's benefits? Because, of course, it is efficient, accurate and economical to shoot ... not.
My 6.5-300 Wby delivered 3,400 fps with a 140, but required a barrel setback at 750 rounds, which lost me 3" and about 150 fps. I'd be very lucky to get 500 more from it, and likely less. It still takes 80+ grains of powder to get this 3,250 fps from the now 27" barrel. Effectively, I burn 15 grains more powder to best the .264 by 100 fps.
At 1,000 accurate rounds per barrel, using a $350 barrel it cost $150 to install, this is 50¢ a shot just for burnt steel. Just for fun, assume you live next to the gunsmith and shipping costs nothing, and assume you don't mind going without the rifle for the several weeks it takes to get your work done, months for the big names.
My 6.5-284 uses 53 grains of powder to deliver 3,000 fps from a 26" barrel. The first barrel started to go at about 1,500-1,600 rounds, tossing those occasional fliers we all take credit for, at first. Had I been shooting to F-Class standards (10" 10-ring at 1k), the barrel was already gone then. I dogged it to 2,037, and by then it cost me in steel match standings and delivered 1-1/2" groups when I finally tossed it. I am 1,000 rounds into the new barrel and already I am thinking in the back of mind about the cost (33¢/shot) and aggravation to rebarrel every time I pull the trigger.
The 6.5-06 is a ballistic twin to the 6.5-284. To tell ourselves that we can drive the same bullet at the same speed with the same powder charge, but somehow see an improvement in barrel life is delusional. There are cartridge designs which put convergence inside the case neck that may reduce throat erosion, but the 6.5-06, with it's cordite-style 17o shoulder is certainly not among them. If anything, the sharper shoulder of the 6.5-284 would produce less erosion, all things being equal, which they otherwise are.
My .260 has about 900 on it, and at 43 grains of powder and a 140 at 2,850, I'd reasonably expect F-Class accuracy for at least another 1,000 rounds. If I do get close to 2,000 accurate rounds from this barrel, it's only 25¢ a shot in lost steel.
A .264 will use about 65 grains of powder to achieve 3,100 fps with a 26" barrel. I don't know how many rounds to expect, but it certainly has to be about 1,100-1,200 if it tracks with the other 6.5s that I DO have experience with.
There are always exceptions, and a friend of mine has a Kreiger .300 WinMag barrel with over 4,500 on it that still delivers 1/2 moa, with the occasional flier that could be the barrel. Feel lucky?
There is the question of powder economy, and even availability, but since we're performance driven, we don't care that we burn another 20+ grains of powder to get about 200 fps over the lowly .260, or even another 10-15 grains to get about 100 fps more than the very popular, but well known barrel burning 6.5-284.
While no one says much about it, the vast quantities of slow burning powder is not without additional cost: fouling. Hard carbon forms at the throat and impairs accuracy while increasing pressures.
I have to clean my 6.5-300Wby every 20 rounds to keep pressures at bay. The 6.5-284 should probably be cleaned at 80 to 100 round intervals for best performance, maybe more often for real match accuracy.
If used as a hunting rifle, or even as a secondary gun, I can see it. My 6.5-300 Wby uses 19 minutes to get to 1k, and kills deer like lightning, but at the rate of barrel erosion and as often as it must be cleaned, I only use it to shoot distant deer and groundhogs and I really need other rifles to actually enjoy shooting and/or attend matches.
As a primary rifle, where we might shoot 50-60 rounds during a day out, we either talk way more than we shoot or we put a new barrel on the gun every year, possibly more often. 60 rounds a session is 20 days of shooting, IF we get 1,200 ACCURATE rounds.
I honestly don't care about spending $400-500 every year for a new barrel and more if we re-bed every time, which we should, but I DO care about the two-three months downtime I'd see.
Losing at least one cartridge from your mag capacity probably won't matter, but that's another aspect. On rapid fire strings fired at some of the tactical matches, I begrudge my 4-round capacity with the 6.5-284, and, depending on rifle selection, you may find yourself down to three.
Accuracy is especially critical in this equation, since the whole reason to go to a .264 is to extend our range over lesser cartridges. Without accuracy, our max range gets closer, not further. While I believe that the rifle construction is more critical to accuracy than a few cartridge dimensions, large quantities of very slow powder can be difficult to get to burn consistently, and without very low velocity deviation, long range accuracy really does not exist.
We normally shoot a couple or three long range rifle matches a month. We attend quite a few steel matches, tactical/precision matches and shoot F-Class every month at Quantico. For F-class, my daughter shoots my .260 tactical-style rifle and I use a 6.5-284 tactical-style rifle, both shot from Harris bipods and regular RedTac rear bags. Our scores are usually within one or two points of each other and we fight each other for second or third place. We are usually right there with the "serious guys" shooting dedicated F-Class rigs and benchrest guns. Why such similar scores between the .260 and 6.5-284, even though they're 100 fps or more apart? Not because of anything to do with ballistics, but because I call wind for both of us and this is where my calls put us. The point of this is that while we might see a certain velocity improvement with the .264, if rifle accuracy and shooter accuracy are not on top of their game, any perceived advantage is lost.
If I were spending your money for low recoil, long range performance, I'd buy another 6.5-284. If I wanted more, I'd go to a 7x300 short mag or even a .300 WinMag.
