- Joined
- Feb 24, 2023
- Messages
- 2,785
I put together a 25 Western a while back and have just been loading mag length at 2.980 in my Hawkins Hunter PRC/Saum magazines. I may or may not have blown a few primers out finding the top end of my load (I certainly found it!) so that brass was trashed. We had a pretty crappy day weather wise yesterday and the kids were driving me insane so I snuck out to the shop for a bit. Halfway through I thought maybe someone else could benefit from this so I took some pictures. It's a really simple process. By doing it with a fired case from your rifle, you can cut down on variance from the standard modified cases that are sold compared to your chamber.
Tools Needed:
Bench Vise
Scrap 2x4 Chunk
Drill Bit Set
Drill
5/16"x36 Tap
9/32" Drill Bit specifically
Method for opening up the neck
(Tap and Bit Set From Amazon - $10)
First step is to create a jig to hold your brass. It get's really hot drilling it out and you don't want to pinch it or deform the brass. I made a jig out of a 2x4 chunk that I drilled through and then cut in half. This encapsulates your brass letting you clamp it in your bench vise.
Clamp the brass upside down in your vise and get to town with the drill bits. I stepped up incrementally from just bigger than the primer pocket all the way to 1/4" and then finally the 9/32". I used a little Kroil on the brass just to help. Plus it smells good when it aromatizes! (Joke, but not really, it does smell good.)
If you have a drill press, that's the ticket. If not, make sure you are going as straight as you can. You want this to be as true as possible. Clean the brass out when you drill out to the 9/32" and then it's time to tap it. Go slow and straight. Tapping brass isn't hard at all. At this point you can choose to leave it as a fired case or you could run it through your sizing die so it matches your sized brass exactly. If you use bushing dies, just take the neck bushing out of it.
Spray it off with some brake cleaner and you're almost home free. It just so happened that my 6.5cm expander mandrel (0.2615) worked perfectly to open the neck up just enough to easily slide a .257cal projectile in and out of the neck. I don't want to speculate on ways to do it without an expander mandrel but I'm sure there are plenty.
Now you're left with your very own modified case that came straight from your rifle.
Tools Needed:
Bench Vise
Scrap 2x4 Chunk
Drill Bit Set
Drill
5/16"x36 Tap
9/32" Drill Bit specifically
Method for opening up the neck
(Tap and Bit Set From Amazon - $10)
First step is to create a jig to hold your brass. It get's really hot drilling it out and you don't want to pinch it or deform the brass. I made a jig out of a 2x4 chunk that I drilled through and then cut in half. This encapsulates your brass letting you clamp it in your bench vise.
Clamp the brass upside down in your vise and get to town with the drill bits. I stepped up incrementally from just bigger than the primer pocket all the way to 1/4" and then finally the 9/32". I used a little Kroil on the brass just to help. Plus it smells good when it aromatizes! (Joke, but not really, it does smell good.)
If you have a drill press, that's the ticket. If not, make sure you are going as straight as you can. You want this to be as true as possible. Clean the brass out when you drill out to the 9/32" and then it's time to tap it. Go slow and straight. Tapping brass isn't hard at all. At this point you can choose to leave it as a fired case or you could run it through your sizing die so it matches your sized brass exactly. If you use bushing dies, just take the neck bushing out of it.
Spray it off with some brake cleaner and you're almost home free. It just so happened that my 6.5cm expander mandrel (0.2615) worked perfectly to open the neck up just enough to easily slide a .257cal projectile in and out of the neck. I don't want to speculate on ways to do it without an expander mandrel but I'm sure there are plenty.
Now you're left with your very own modified case that came straight from your rifle.
