Best Way to hone the neck of a FL sizing die: (home workshop)

[JWFilips]

Hi Guys,
With the acquisition of my "new to me" Spanish 1916 mauser ( 7x57) I have run into an issue with the stock sizing die sizing the necks to about .285 id I then have to open them up for the bullet size I need (.290") & it is really over working the brass...even with annealings.

Now I have opened up many of the fl dies for my other rifle calibers for shooting cast bullets with Carborundum papers on a dowel but with this one, I really have to open it up .005"/.006"
Any helpful tips for a guy with a home workshop ( no lathe)
Thanks
Jim

 

[Kevin Stenberg]

I will be watching intently.
Jim when using a dowel and Carb. paper. How do you keep the paper tight on the dowel when inserting it into the die?

 

[JWFilips]

Kevin,
After applying lots of oil Turn it in like a screw the opposite direction it wraps ( it will compress the wrap enough to allow the hand drill to turn it)
At least this is how I do it ( & I'm asking for answers )

 

[Ian]

Some brands and calibers are more easy than others to enlarge. The ones where the neck is the smallest i.d. of the die are the simplest, the ones where the neck is larger than the top plug threads can be difficult to hone without tapering the neck.

I use a drill bit in a drill press. Painter's tape folded around the bit, strip of sandpaper sandwiched between tape, whole deal wrapped around the bit for a tight fit in the die, a little transmission fluid for lube, hold the die and turn it on. Rinse and repeat. To remove a LOT of metal, 80-grit aluminum oxide paper run dry will break through nitride coatings better than carborundum, then polish with wet carborundum/emery paper.

 

[quicksylver]

Jim...when lapping with a dowel and paper I cut a slot in the end of the dowel ,slide the paper in with equal amounts sticking out either side and wrap in opposite directions...you can cut the paper longer giving you more over lap as you progress..

 

[Intheshop]

JW,as a very slight tangent google up images for;

Speed lathe

Sunnen honing machine

Then,think seriously about whether you want the "tooling" fixed in the head/machine,or the part.It's gonna have to be one or the other.

Along with that,do some research on "finish".Meaning,look for an online scale describing finish,in microns,I believe.Then decide on what your requirements are.Just a few decisions before nailing down the process.

 

[smokeywolf]

I have run into an issue with the stock sizing die sizing the necks to about .285 id

J.W., what is the O.D. of the neck when the I.D. is .285"?

 

[JWFilips]

Smokey,
I just formed a new case ( once fired 30-06 RP to 7 x57) Just to be accurate with my measurement for you since my other cases have been fired about one dozen times
The numbers are smaller then I said above The full length 1960 era RCBS 7x57 die leaves the ID at .280" and the OD at .310"
So I'm really working these cases expanding them to load a .291" bullet
Jim

 

[smokeywolf]

Was just figuring on what the I.D. on the neck portion of your sizing die would have to end up. Would .318 be about right?

 

[JWFilips]

Smokey,
I think that only brings my ID to .287" I would like .289-.290" So I think the OD would be .320"

 

[Brad]

What about a Redding bushing die? They are the cats meow. Pick a size that gets the neck tension you want and get rid of the expander from the sizer.

 

[JWFilips]

Ian,
I'm still trying to visualize your system using the painters tape and drill bit?

 

[JWFilips]

Brad you are certainly dead right! However they aren't free
If it were a Scope mounted 7mm Mauser with a super bore I would make the investment. But this one is just another diversion in the hobby.
Nothing special just enjoyable to get it back to working condition. & Occasional shooting. Just trying to simplify the loading, on a shoestring

 

[Brad]

Nothing in life is free!
I too would like to see a photo of Ian's set up. He lives to do this stuff.

 

[Blaster]

Maybe you can use the Lee Collet Die, if you don't need to full length size or bump the shoulder.

 

[Ian]

I would stop at about .315". Once it's fired, reconditioning the neck to .290" might not be possible with the die at .320" due to spring-back.

Really, Brad has the best solution here. I'd save that old RCBS unit for another day (they still make them, but not like they used to!) and then you can select different bushings as needed for all the different neck thicknesses you'll encounter. Unless you're turning necks to a uniform size, it's tough to hit the mark every time with a single sizing die. I know the dies are expensive, but you get what you pay for.

Let me go check and see if I still have a bushing neck set for 7mm-08, if I do, you pay postage and I'll loan it to you to try out. It will just size the fire-formed necks but should be nice and straight since the case head is the same.

 

[JWFilips]

Thanks Ian.

I have a question; If one were to drill, ream and taper a small piece of steel to the proper size ( let's say .315") would it not be possible to place it between the cartridge case and the top of the press , and in effect use it as said bushing? to let us say, size 1/2 of the case neck?

I really was hoping this over size 7 mm mauser (7.4 mm) would act the same as my oversize Sauer 8mm mauser ( 8.4mm). With that one I do not resize the cases at all.
I just reseat the bullets in the shot cases. ( bullets are set into the throat with both rifles ....only light loads are used BTW)

 

[smokeywolf]

Are you talking about making a bushing that screws into the die station on your press and has an internal dia. of the desired neck size? Don't forget to have sufficient thread to employ a lock ring. As long as you're not putting too much downward pressure on the unsupported case body I would think that should work.

 

[Brad]

I will be making JW a simple die. I can make either a threaded die with a hole of the desired size with a small countersink at the bottom edge. It would be used to neck size only.
What could be better is the same idea but with the top bored to take Redding bushings. Cost increase comes from needing to buy bushings but this is offset with ability to change size at will.
Bushing type die is more work but not overly so.

 

[Brad]

Here you go Jim. I made the opening at the same angle, or close as I could get, as the shoulder on a 7x57 chamber. It lets the neck center nicely. I used a little case lube on the neck of an 06 case and instantly had a .318 OD neck.