I have been shooting the 6.5 brm for about 6 months, and have used the load provided by EABCO web. I have wondered if the 6.5 brm and the 6.5 bullberry imp are similar enough to use the loads from that web site as starting points. I will probably call Mr. Brown and ask, he seems very friendly and helpful. I looked, but the heaviest bullet for the 6mm bullberry improved was only 80 gr.
I have looked at data from a web site
http://stevespages.com/243_16_90.html, but have never tried his load data...
Will also tell you up front... I'm a noivice reloader, so please do not use this as advise... just info.