Hey folks, I have been visiting this site frequently but just decided to jump in to the discussion. I have been wanting to incorporate malfunction drills into my training. What I am wondering is could I cause any damage to my firearm buy loading expended brass into my magazines? It seems like it should be fine but every time I think about the sharp edge of the brass jamming into the chamber I cringe a little. I know I could use snap caps for this but they aren't cheap and I worry I will lose them in the dirt or across the firing line at the range as I plan to try and clear the malfunction quickly without losing sight of the target. Any thoughts or advice would be appreciated.
If you take a block of aluminum or preferably steel and a 27/64" drill bit with a 118 degree crown (point) and drill a shallow hole (I'd go about 1/4" deep at the most) in the block, you might be able to gently tap an expended .40 cal brass into the cone at the bottom of the drilled hole. It would act like a reverse flaring tool. I've never done this so I don't know if it would work, but Hey! You never know.
I'm not too sure how well a brass-only load would work in the magazine. I think it'll cause the jam you want but with a the live round above the brass-only