Back in '95 I used 53.5gr of the old AA2015BR behind the 250X in my 35 Whelen AI for 2600fps. Most know that I have used R15 for the Nosler/Speer 250s but at much higher ( and pressure, of course) velocity. I have never used any 250 on game other than that old 250X ( I still have some). It plowed through just "some" plains game in South Africa and later the 200X ( I use H322 with) did the same. I know 2015 has changed names through the years, but I never bought any...I used that 200gr more than anything. I have a good store of H322 and near as I can make out in my Google research it is very close. I figure I can start at 49-50 and work up slow with the Nosler & Speer for 2600? I also used the BR2 primer with the 250X/2015 load but Fed 215M with the R15. Anyone know how close they are to each other? thanks. Rev Jim