I have been tinkering with .17 win super mag brass. I pulled the bullet with a pair of visegrips. Dumped the powder, trimmed to just past the shoulder, and champfered inside and out. Got some .258 65 gr cast bullets from Western Bullet Company. I ordered these before I realized I needed a healed bullet. But made them healed by trimming some of the base band with a pocket knife. They fit great and look cool. I sacrificed one of the brass, to see if it would fire. It took three attempts,  but it did fire the primer. I am going to order a new main spring to see if that helps. Now, what powder? Smokeless? Straight Black Powder? Or BP with some sort of smokeless to help with ignition? Looking for suggestions. Looks promising so far. Having fun with this and much incuriged with the results so far. Shoot as fixed ammo? Breach seat? Life is an adventure! Richard.

     I've been shooting 75 gr bullets with 4.6 gr AA9, 5.5 gr 4227, and 2.5 gr Herco with good results.

CHRIS
RGChristensen

black powder,  safe and simple   art

Thanks to everyone that contributed. Its certainly a work in progress. Labor intensive to! I got all of the bullets puled from a box of 50 .17 win mag rimfire. I got them all trimmed to about .950. Still working on an idea to cut some of the bottom band away to make healed bullets. Another work in progress project in its self. Hope to fire a couple of them tomorrow. Probably try 1.5 to 2 gr. 3031 or Unique, since I have that on hand. Also received order of bullets and brass to try loading .32 Long Colt. Have to hold off on that a day or two. Thanks for all of the help! Richard.

Easiest way I found to pull the bullets is to run them up through the press without a die, grab the bullet with a pair of wire strippers, then lower the ram. If you want to save the bullets there is a tool called “Grip and Pull”.

Trim the case to 1.150, then expand the neck with a very slow taper sizing mandrel, or multiple mandrels. 2 calibers is a long stretch. If you do not trim first, you lose a lot to split necks. 

I over expand then full length resize the case with a .280 die blank. These are generic and have a .280 bore that is ready to chamber for any 280/7mm cartridge. Made by PTG, generally in stock at midway or PTG.

If you fire a couple of loaded .17 rounds in your rifle, you have fire formed cases to measure. That will let you know if sizing to .280 will work in your chamber. Trimming those back to 1.125, you will probably be able to seat the bullet with thumb pressure.

The 65 grain Western bullet works fine out of the box.

Depending on what action you have, powder choice could be critical. There’s a big difference between a Stevens favorite and a 44 1/2. Black powder is safest for all actions. Stronger actions you can experiment some. I have had good luck with 2.7 grains of Vihtavouri 3N37.

Lots of labor, but kind of fun to get something of the wall and out to the range.