I have an older Sumatra that likes .250" and .249" slugs. All NSA work great from sample pack (sample pack is nice, its what i started with) then i got the Boat Tail 52 & 55g, it likes them too. 52gBTHP is mad beast mode. W/ these i get great accuracy out as far as i have steel plates set up=160yrds and under. I average 1060fps=90fpe w/ still carries 60+fpe at 160yrds. W/ NSA quality its really about how much drop you want at long range and what kinda game im trying to take down. Some weights are over kill on the little critters. They fly like bullets cause thats what they are, so watch whats out there. I live rural, in the hills, horse owner, lots livestock w/in a 1000yrds. Pellets dont fly that far, these do. My Eagle Claw is a Seneca, it dont like the .249" but so far likes the .250" in 43g and 33.5g really nice, ill test it w/ these when i get more. Sumatra loves them, its not a Seneca. They shoot flat. My fav is the 33.5g cause both my rifles likem and the Eagle Claw is not quite as powerful as the Sumatra even though i tuned w/ new spring to 88fpe w/ the 43.5g. My Sumatra is at Will Piatts shop getting gone threw, im sure itll likem even more upon return. It made 98fpe w/ the 55g BTHP before i sent it off. Air Venturi sent me a longer hammer spring for the Eagle Claw, it was only making 55fpe out the box and didnt like any slugs. Now it loves the .250". I order a new batch every month, like right now, add'n to cart. NSA rocks!