Even though the Sierra people had different results, RL25 did the best in my Sendero 26", but powder lot & alot of things come into play. Retumbo is a hair slow, but in 115gr & heavier bullets it is worth trying & according to Hodgdon 2006 Annual, it gave better vel. than any other H. powder for bullets 115 & over in the smaller, std. case, much less the bigger case. I will try RL25 next spring, Lord willing to see if it can edge RL25 in my 25-06AI with the 125gr. Wildcat bullet. And yes as I said a couple of weeks ago, the long tube helps.