In the modern, strong rifles, Winchester '92 and modern clones, Marlin 1894, you can go up to 7.2 grains of Bullseye with up to a 230-grain bullet. Very accurate and consistent load, these from my Fouling Shot article some time back:
Table 1
Side-by-Side comparisons fired the same day with representative .44-40 Factory and *Group 2 (+P) loads fired in two Vaqueros using the same .44-40 cylinder, with 19.5” H&R Single Shot rifle for comparison:
Ammunition all assembled in fireformed and resized Starline brass with Remington 2-1/2 primers.
Load Description_____Ruger 5-1/2"______Ruger 7-1/2"____H&R 19.5"Backpack Bunny Gun”
--------------------------------Cyl.Gap 0.003"-------Cyl.Gap 0.002"---------Solid barrel
Rem-UMC 200 JSP______n/f___________1017, 16 Sd______1231, 19 Sd___Pre WW2 factory Balloon Head
R-P 200-gr. JSP____872, 24 Sd_______942, 21 Sd_______1159, 29 Sd___1960s, Bridgeport, CT production
R-P 200-gr. JSP____867, 13 Sd_______920, 19 Sd_______1106, 32 Sd___Current Lonoke, AR production
W-W 200-gr. JSP___856, 19 Sd_______886, 29 Sd_______1105, 25 Sd___Current East Alton, IL production
Rem .427” 200JSP 24.5 RL7__902, 31 Sd__1044, 24 Sd__1232, 30 Sd___Safe in Winchester 1873s
*43-230G 10 24.5 RL7___1127, 28Sd__1252, 32 Sd___1439, 25Sd___+P Modified John Kort Design
ColMeanV (gain) FPS-----------977-(REF)-----1061 (+84 over 5-1/2")-1256 ( +195 over 7-1/2")
*Group 2 +P loads for Ruger, S&W 544, Marlin and Winchester 92 only
These are recent chronograph data from my Rossi 1892 for an upcoming Fouling Shot article:
Velocity of Typical .44-40 Winchester loads in Rossi Puma with 20” barrel:
Ammunition___________________Vel@15ft, Sd, ES
Winchester 200 JSP factory load____1158 fps, 18 Sd, 51 ES
Handloads all in Starline cases, with Remington 2-1/2 primers
Remington 200 JSP .427", 24.5 RL7__1355 fps, 22 Sd, 74 ES Safe in Win. 1873
Hornady 200 XTP .430", 28 IMR4198_1642 fps, 20 Sd, 63 ES Group 2 +P
Matts .430” 215 LFN 28 IMR4198___1701 fps, 12 Sd, 41 ES Group 2 +P
Matt’s .430” 215 LFN 7.8 Red Dot___1273 fps, 15 Sd, 57 ES Group 2 +P
Matts .430” 215 LFN 35 Goex 3Fg___1172 fps, 28 Sd, 98 ES Safe in Win. 1873
Accurate 43-230G 7.2 Bullseye______1167 fps, 8 Sd, 25 ES Group 2 +P
73 de KE4SKY In Home Mix We Trust From the Home of Ed's Red in "Almost Heaven" West Virginia