7mm Bullet Nose Sizing Drama

[jmoore]

Got an XP-100 with a custom 7mm TCU barrel the other day and discovered it won't accept 145gr RCBS bullets with the noses sized to 0.277". Looks like it will need 0.276" or a skosh smaller to work.

Anybody have a source for such an odd duck size? or am I going to have to try and mod a 6,5mm die? Hoping it doesn't need to be ground to size, lathe would be much more convenient if it comes to it.

[high standard 40]

I have a special H&I die that I had made that accepts the bushings that are made for the Redding S dies. Once you have one of these, your choices of sizes available is almost endless. Sadly, the gent that made mine has retired. It shouldn't be too hard to make with a lathe, if you know anybody who has one and is willing to help.

[jmoore]

Excellent idea! Shouldn't be too hard to make.

BTW, I have made an adaptor for the Lyman dies for the Lee push through sizer system for similar reasons, but it doesn't work for this application.

[jmoore]

How are the bushings retained in the adaptor? Custom nut for the press, or a thin washer, or ???

Leaning towards the thin washer approach to start but there's not a lot of threads on the stock Lyman retaining nut.

[high standard 40]

My die uses a washer that he made on the lathe. The hole in the washer is tapered.

[7br]

You might check with Buckshot on the castboolits bulletin board. He made one up for me for nose sizing a 6.8 spc boolit. Come to think of it, I got a new mold for my spc and don't really need my die. Drop me an email at mabarb@att.net and I can send pictures.

[high standard 40]

You might check with Buckshot on the castboolits bulletin board. He made one up for me for nose sizing a 6.8 spc boolit. Come to think of it, I got a new mold for my spc and don't really need my die. Drop me an email at mabarb@att.net and I can send pictures.

Buckshot made my die as well, but I hear that he has retired.

[jmoore]

My die uses a washer that he made on the lathe. The hole in the washer is tapered.

Well, that was one of the easier projects I've taken on in some time! Used an old RCBS 0.354" size die which had no purpose, bored it out about 0.001 over the Redding "S" die OD and about 0.005" short so the hardened washer I used would clamp it in place. Had to turn the washer down and thinned it to 0.050" for ~0.060" inwards, so now it's stepped. ID was big enough, as is.

Have to make a "pusher-outer" next. Probably just turn down the RCBS's core to suit both the 0.275" and 0.276" "S" dies.

ETA: Done did. Much softer steel than the die body!

Now to size some bullets and work up some loads. How hard can that be?

[high standard 40]

Jonathan,
On some of my "S die" bushings I have had to increase the taper to prevent shaving lead. I have also lapped some to get the perfect fit I needed. Good news is it's easier to lap that bushing than it is to lap an H&I die.

[jmoore]

The "S" bushing trick seems to be just the thing. Once I had removed the protective gunk from the H&I die set and replaced it with real lubricant, that is! Thought I was going to break the press for a while. Amazing what a thin film of the wrong petroleum product will do.

My "S" bushings are the TiN coated versions, BTW, so if honing is needed will buy a bare steel one.

Able to just barely insert the bullet nose into the muzzle the full distance, so should be pretty close to optimal.

Had other projects take up the rest of the weekend, so no range results, yet.