modifying a Lee minne ball mould

[omgb]

I have a couple of Lee minnie moulds in .58 that really don't shoot well. My thinking is that they are a tad under sized and when fired, the skirts blow. A Lee target minnie shoots great in the same gun so here's my plan. I want to take the over-sized minne mould I have and turn down the center pin. This will make the base cavity shallower and smaller. I should then be bale to shoot stiffer charges without blowing the skirt. Val Forget of Navy Arms did something like this to the old Shiloh Stakebuster mould so that he could fire 180 Grain 3F charges in his old Hawken Hunter rifle. Have any of you tried this? Lacking a lathe, I figured I'd grind off the retaining rivit, and chuck the piece in the jaws of my drill press. I was thinging a simple file and emery cloth should do the trick. Opinions?

[shooter575]

I have replaced the rivet with a screw before.Think I used a 6-32?That screw would make the mandrell to chuck up to.If you dont bugger up the flanged belt on the core pin shouldwork OK with a drillpress and file.

[Buckshot]

................Do as Shooter575 suggested. Drill and tap for a #6, 8 or 10 screw and then cut the head off one and use that for the chuck to hold on. If you have a compound vise, use that as a tool holder. Grind up a tool and clamp it in the vise jaw. Crank it in to cut on the spinning core pin.

When I got seriously into muzzle loading several years ago, the guy I shot with was forever making up new core pins for his various Minie' moulds. But he had a lathe. If it doesn't work out for you, you can get a Lyman 575611 I think it is. Drops a 530gr Minie' with thick skirts for heavy charges.

..............Buckshot