6/250

[dave]

I fed some 6br rounds in my standard mag vangaurd that is in .22-250 and they fed well obviously they didnt chamber but i dont see what all the fuss is about? Is it more to do with projectile choice and feeding problems or the small fat case?

[jb747]

JB, why would there be such a velocity difference between the nosler and sierra in the same weight?

I haven't followed it up to any extent, but different amounts of bearing surface, or a harder base can both affect the speed and pressure. Not all bullets are exactly .243 either. There is a bit of difference either way, and that will raise or lower pressure accordingly (this was quite evident in one of my 223s).

In the 6*47 the 75 Vmax are about 200 fps slower than expected, and in the order of 350 fps slower than the Sierra 70s.

[jb747]

I fed some 6br rounds in my standard mag vangaurd that is in .22-250 and they fed well obviously they didnt chamber ...

I don't have a BR round to experiment with, but I've played with quite a few other oddballs (for want of a better term). Feed is in the hands of the gods. Some things work perfectly, whilst others are so problematic as to be more or less impossible. In particular, small action Remingtons when used with short rounds are a pain. For instance, the 221 Fireball gives a lot of grief in the Remington (even when modded by the factory for that cartridge), and it won't work at all in a Rem chambered for 223. On the other hand, it feeds perfectly from a Sako 461 or 491....