Thread: Another 260 Improved

Well after reading all the 260AI stuff of late, I decided to crank my project into G
I've gone down a different path to all you 40 degree Ackley disciples and made up a 260WI (Whitley 30 Degree Improved) My train of thought was based on the fact that a lot of your current modern rounds like 6.5 Creed, 6.5 x 47L, 6mmBR and the likes are all made with a 30 degree shoulder, this must be for good reason. So I discovered the Whitley range of improvements and got a reamer cut over a year ago in the States. Also bought a Shilen match barrel to go with it.
It's now all screwed together on a T3 action and tonight I ran some fire forming rounds through it to check the chamber before the rifle gets its final finish.

I started with 43gr 2209 behind a 129gr Hornady, @R93 for the info here thanks and also made some 44gr & 45gr to see if I needed more grunt to form the shoulder, 43gr was enough by the looks as the other two didn't show any better form nor pressure signs either. I'll save myself some powder.

Standard Lapua 260 case with the newly formed 260WI



3 different loads, same result



This 30 degree is a lot easier to form than my last Ackley I had.