303 Berdan primed to 44 mag shot shell

[William Yanda]

Greetings
I have acquired some 303 Berdan primed brass which I intend to convert for 44 Magnum shot shells. This will be a dozen or so, not a major quantity production. When it arrives, I plan to convert to boxer primers and fire form in my four-tenner, then cut to length. Any suggestions?

[EDG]

How do you plan to convert to boxers?
I think it would be a lot less trouble to start with boxer primed brass.
I have about 75 new .30-40 Krag cases (WW and Super X) that are cut to length for the .445 Supermag (1.610).
They have a slightly larger rim diameter than the .303 but are the same head size. If you are interested send me a PM.

[Outpost75]

I don't know what length you are planning to cut your .303 British to, but Starline 5 in 1 blank cases are 1.55" long and work well in my .44-40, .45 Colt and .45 Auto Rim revolvers. To roll crimp take an old Lee .308 Win, 7.62x54R or .38-56 seater die and cut 1" off the base, then adjust the seating plug to position a Walters card wad about halfway down the internal shoulder of the die and set length to "bump" the case mouth against the shoulder cone, for a nice, professional looking crimp. The 5 in 1 brass has a large .12" flash hole to prevent set back when blanks are used in revolvers, but this isn't an issue if only light Cowboy charges are used with the shot loads. I use 1/3 oz. of shot and 5 grains of Bullseye.

You can back off the crimp die to do the same thing with full length .303 British, .444 Mag. or fireformed 9.3x72R or 9.3x74R cases to make brass .410s and load .44/.45 caliber cut card and fiber wads with 15.5 grs. of #2400 and 1/2 o.z. of shot.

The .303 brass makes a 2-1/4" long shotshell which works well in the 2-1/2" .410 chamber.

It is also fairly easy to drill out the fired Berdan cases using a 1/16" drill through the firing pin indent to make a new flash hole entirely through the web of the case. If drilling does not entire remove the Berdan anvil which is formed integral to the case head, finish that task using a 1/8" ball burr in the drill press to smoothly clean up the bottom of the primer pocket, then finish shaping the primer pocket forming the remainder of the Berdan primer cup in the Dillon 600 swager using the large primer head. You can then reprime the modified brass with large pistol primers. If that attempt fails, you can always drill the primer pocket and case web out with a C gage or 6.1mm drill and chamfer the edge of the pocket with a 3/8" or 9.5mm drill and then use 209 shotshell primers. This is the common practice in Europe for converting the old 11mm military Berdan cases to reload with black powder.

[Eddie2002]

I was playing around with converting large berdan primed brass over to boxer and didn't have any luck doing it at all. Tried the copper bushing method shown on U-tube and ended up with the primer not seating deep enough. I tried drilling out the berdan anvil but found that there wasn't enough metal under the anvil and ended up drilling through the bottom of the case. With the smaller berdan primers it is possible to crush the anvil with a punch and then drill a new flash hole then crush the edges of the primer hole with a ball bearing down to fit a boxer primer but that is a lot of work.
The most reliable way was to find a brass tubing that had the correct OD and ID and cut small bushings that were soft soldered into the case. Only had a few inches of tubing of that size so even that ended being a bust. I've also heard about converting over to 209 shotgun primers but never tried it.
It was a fun little project but I didn't get anywhere with it even though I learned a lot.

[pworley1]

I have converted Berdan brass to use shotgun primers by drilling out the berdan pocket and chamfering the edge to accept the larger rim of the shotgun primer.