For years I used Triple 7 in my 24" Huntsman with great accuracy and no problems. The first shot from the clean barrel was always in the group and I lived with the patch between shots, greasing the plug well to avoid sticking, and doing a complete clean after shooting. Clean up was very easy with warm water and no solvent needed. I fell to the appeal of BH209, with it's adantages of no more stuck plugs, no patching between shots, and being non-corrosive* I have the asterix there just like they do on the container! And the common claim was, "just treat it like a standard centerfire." I was never able to replicate the accuracy I got with TS loose powder.
So, I intially would sight-in right before the season and hunt with a fouled rifle. After last season I found very heavy rust pitting in my stainless barrel. So this year I dry patched after sighting-in to removed most residue, thinking this would help. BH209 does not shoot the first shot from a clean barrel into the group, that is why I needed to hunt with a fouled bbl. It didn't help, more corrsosion to the extent that I will be sending her to Ilion for a new 26" bbl. I have never had a similar problem with any centerfire rifle, chrome-moly or stainless.
So, I will be going back to TS and will gladly accept greasing the plug, patching between shots and doing a nice easy clean after every day a shot is fired. The BH209 residue had a very greasy consistency (so much that I though it was impossible for it to cause rust!) that was difficult to remove. So much so that I used an ultrasonic cleaner for the plug, which did work well. For me the disadvantages of BH209 outweigh those of TS, especially when BH won't perform like TS from the clean bbl that is needed to prevent corrosion in hunting situations.
So, this concludes my rant. But I do hope sharing my experience will help someone avoid learning the hard way as I did. Have others had similar problems?