More powder,same velocity

[Downwindtracker2]

I should have added that the barrels are new,and the longer throated.There is no 243 throat erosion.On the 264 ,Bill did a longer throat to avoid the spikeyness of a short throated 264.With IMR 7828 it takes 2 more grains over book max to reach max velocity of 3100.That was also the only acceptable group,1",I got with IMR7828.I have been told IMR7828 has a narrow window.

The book max for N-560 with 140 is 2990,I'm at 3045,and again.????Understand the book max is CIP not SAAMI,the Europeans have no use for the 264 chambering,they limit it to about 56,000psi.My primers still have half the radius.But then again,I don't have any thing really to compare Gevelot pockets to,the other two magnums use Winchester and Norma.The primers are the soft shelled CCI 250.My lot of N-560 is slower than my buddies RL-22,in my 338WM anyway.The last loading gave a 1/2"group.That's more like what I have come to I expect with N-560.

Bullet do expand,sometimes with very sad results,but these are not Partions, but the slippery boat tailed SSTs.Barrel friction in 264,was the reason I had it rebarreled,the FN barrel had too much lands.

When it' happened,my first thought was that I had broke in the barrel.It's a 24" Douglas.

A 264, if it's nor accurate and fast is not worth the effort.