excellent info thank you !I am a little late to this party but just joined and this is my first post. I came into a lot of old Kynock 577-450 brass with Berdan primers and they are almost impossible to find so i modified the cases to take a 209 primer. Here is a shot of a sectioned case.
Attachment 297600
I modified a countersink I found at Lowes to do the job in one pass. The drill cuts a .237" hole that makes for a press fit on a 209 and the countersink is ground to .330" to clear the rim of the primer. I just go straight through the spent primer and use a dial indicator to set the depth for the primer. Here is what the tool looks like:
Attachment 297601
It works surprisingly well and I did at least a hundred like this. The 209 isn't well suited to higher pressures and will leak if you get too high. I use these mainly for smokeless to black type of loads for target shooting and haven't had any troubles. They push out just fine. Here is a shot of the lathe set-up.
Attachment 297602
I can't say that it will work in your situation but it got that old brass working again. They definitely will light off the powder as the SD's on these are all very low and accuracy is at least as good as with standard primers. Good luck, Squid Boy