Webley Mk IV Load

Register to hide this ad
If you really mean a .455 Mk IV an not a Mk VI, I wouldn't go there. The Max load is 4.5 gr Bullseye for a 225 gr lead bullet. And those are .45 AR specs not .455 Webley.

If I really wanted to shoot it I would choose blackpowder. I know they used smokeless loads in it back then, but velocities were really low. And I think it was a cordite load.

If it's a Mark VI I would try 3 grs first and chronograph it. If it gets under 450 fps you are risking a stuck bullet.

Your gun your fingers. But this is my 2 cents.
 
Last edited:
Sounds better than the 4.0 grains considered previously. Don't mind me reposting same answer as before, but actual reloading data for Mark VI be scarce.

From 1996 Alliant Reloaders guide for .455 Webley

Max loads with 265 HB RN L, CCI 300 primer

3.8 gns bullseye for 750 fps 12,600 cup
3.4 gns red dot for 685 fps 12,300 cup
3.6 gns green dot for 690 fps 12,400 cup
4.3 gns unique for 800 fps 12,600 cup
4.9 gns herco for 790 fps 12,700 cup
6.8 gns blue dot for 770 fps 12,600 cup

Have loaded for Webley Mark VI, and purposefully avoided bullseye and used lower charges of unique for less pressure more case fill. Remembering Alliant's loads are for hollow base bullets, and solid base bullets may give more pressure with same charge/col. Both of my Webleys (Mark 1 and Mark VI) have .449 cylinder throats.

Personally would prefer unique, and certainly not load close to max for a Mark IV. My memory ain't what it used to be, but seem to recall only the Mark V or Mark VI were designed for smokeless powder.
 
Test on the .455 Webley Mk IV using .45 AR Star line Brass with 3.5 grains Bullseye behind a .455 262 grain cast LRN Bullet: Standing/Off Hand-
good accuracy and printed 2/3 inches above POA at 3, 7, and 15 yards.
At 25 yards accuracy was erratic due the shooter's (Jimmy) wobbly knees.
Negative signs of over pressure/
 
Back
Top