I'll second what Quick has said...the Cast Performance 405gr WLNGC is 1 awsome bullet...you can try a couple different powders to get you to the velocity you want...but I have had my best luck with Hodgdons 4198...it works well with cast bullets as well as jacketed...I personally use Remington nickle cases...Remington 9-1/2 primes...I also use a Lyman " M " die to bell the case mouth it works a-lot better than anyone elses IMHO...and the lee Factory crimp die... using a heavy crimp...and use a chronagraph when doing load developement...and as a disclaimer..." What may be safe and accurate out of my rifle...may not be out of yours...always start low...and work your way up following the powder and bullet manufactures load recommendations".....
From the Hodgdons Annual Manual...for the 405 gr LFP..using Winchester cases...and CCI 200 primers...
These are trapdoor loads...and are real mild compared to some of the heavier loading available...and should do well out of the Handi...and it's a good place to start out with...
H4198...27grains...1279fps...14,200 cup.....31.0 grains...1459fps...17,100 cup...
Benchmark...47.0 grains...1564fps...17,100 cup....50.0 grains...1695fps...22,600cup...
Varget...40.0 grains...1392fps...15,600 cup...50.0 grains...1718 fps...20,900 cup....
These 3 powders I have used and have had good results with...Good Luck..
Mac