Modifying 10ML-II Breech Plug

[ET1]

The purpose of modifying my Savage Breech Plug was to enhance the strength of the ignition and that it did. My new formatted data sheets I will use to share load info will specify which BP was used. Yes, I have more than one type of modified BP that I will be experimenting with. I thought I would forgo any long-winded explanation and will answer any questions concerning this modification.
Now I am not recommending anyone make this modification unless you first address the poor head-spacing that exists with a 10ML-II. Proper head-spacing adds to the improved ignition and really reduces blowback around the primer. Below is a diagram of the recessed BP with proper head-spacing.

[overtheir]

Hi was wondering why you stayed with the vent screw why not upgrade to carbide insert ? last 5 times longer.

[ET1]

Would you believe I drill my own vents? Took a few drills busted to get the hang of it. Once I got on a roll I drilled a good supply of vents to have on hand.

[RS460]

That's great! what kind of jig did you make to hold and center the screw?

[ET1]

That's great! what kind of jig did you make to hold and center the screw?

I basically made a holding plate out of 3/8” aluminum. Drilled and tapped the holes along with a chamfer for the head. The screws are classified as Grade-12 that refers to their hardness. As for centering the drill it was done by eyesight from 2-different angles, 0 and 90-degrees. Even if some are drilled on a slight angle it doesn’t appear to matter. Drill from the bottom side of screw after a good tightness to the plate. Drill press was set at about 800rpm.

[RS460]

Nice set-up. Looks like you used a center drill to start. What size drill bit are you using? Do you use a lubricant to keep the drill bit cool?

[ET1]

No Centre Drill.
.030" bits worked best for me.
Just a drop or two of cutting fluid.

[RS460]

Thanks for the info and pics. I am going to try to make a few.

[ET1]

Thanks for the info and pics. I am going to try to make a few.

Enjoy the challenge. A key element is how much pressure and feed with the drill. I also just drilled roughly half way, retracted drill and brushed away shavings. I was averaging 10 plus vents per drill.