264 winmag vs 6.5 284 win
just for curiosity, why so many br shooters using 6.5 284 ,when it seems to me the 264 is a factory round with superior speed and given that its only .2mm bigger should have almost identical bullet dimensions, giving some very good accuracy. like i said just for curiosity from a newbie wanted to see what the experts have to say, thanks.
Well im no an expert on the subject. In fact i havent been around either cartrige except in terms of research. The research ive done says that the both the 264 win mag and the 6.5-284 are excellent long range calibers but the 264 tends to be leaning on the barrel burner side. With velocities at almost four hundred FPS faster with certain powders its not worth eating a barrel for. Especially since they produce very similar results ballistically.
in 1K BR, the 264 Win Mag is way too much case. It also has a belt.
The 6.5x284 is a much easier case to deal with, and is much better combo of bullet/powder capacity.
With some rare exceptions gilt edge accuracy starts to fall off after you reach 3100 FPS with heavy bullets.
Your mileage may vary
[QUOTE=bigeddie;456401and given that its only .2mm bigger should have almost identical bullet dimensions,[/QUOTE]
A .264 is a 6.5mm, isn't it????
400 fps is most DEFINATLY worth it!!!!! Problem is, you would be lucky to get 150 fps more out of a 264 Win mag over a 6.5-284, (imo). 150 fps may not be worth it (to some).
I could be wrong, though.
wasnt sure abot 6.5mm just did a conversion with calculator and it said .264 inch equals 6.7mm, i havent yet started reloading and dont own a mic. and with the velocity i just usually check reloadersnest.com to check reloads according to whats posted, there is about 350 fps with 160 gr bullet faster for win with same bullet mfg same brass same powder only diff. 2 inches of barrell maybe adding 40 fps to mag? and about 500 fps diff with 100 gr bullet, are those speeds worth it? thanks
The 400 FPS comes right out of the hornady manual. Not all bullets and powder will produce that much difference in velocity but some will......and yes i agree to some people 150 FPS and even 400 FPS is worth burning your barrel for but not really considering that, even though the 6.5-284 CAN shoot up to 400 FPS slower with max loads, it is almost identical in ballistic tables
To clarify what is posted above:
Both use the same (.264") bullets
The 6.5-284 is already a little hard on barrels, the .264 WinMag is worse.
Fouling accumulates much more quickly in the .264 WinMag
The 400 fps gain really is "optimistic" and I doubt test conditions are the same. I have a 6.5-300 Weatherby built by Sid Goodling and it barely gains 400 fps over my 6.5-284, and the 6.5-300 WWH is in a 30" barrel, the 6.5-284 is a 26". Equalize barrel lengths and the velocity difference is less yet.
Accuracy really does drop off a little as velocity increases, and I'm not sure if it's due to the longer powder column shape, large case volumes, heavy charges of very slow powders or exactly what, but most people seem to run the 6.5 bullets between 2,900 and 3,000 with excellent results.
The reduction in drop is academic at known distances, and the reduction in wind deflection (which isn't as much as the "400 fps" would indicate when velocity test conditions are actually similar) is quickly offset by enlarged groups and drastically reduced barrel life with increased fouling.