So, friend, you have discovered that you can get away with it sometimes. Good thing that you were shooting a .303; none of the loadings go to ridiculous pressures.
I would be very leery of trying the same thing in a cartridge which runs at much higher pressure. As mentioned earlier, rifle primers have more snap AND they are heavier material. I just like all the iron or brass I can get, between MY tender eyeballs and 40,000 pounds of pressure.
Now your poor Webley is gonna be 1 round short! You'll have to package your ammo in 12-round lots, like in the Army. Old girl will be so excited that she won't notice!
Oh, it's fun!
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