I need a die to expand the neck of 5.7 brass from 0.224" to 0.260"

[tiger762]

Started using 5.7 brass as 30cal jackets. I have a 0.257" core swage but to use unmodified 5.7 brass I'd have to at least expand the neck ID to 0.260" or more. Let me know your recommendations and thanks in advance.

[garandsrus]

A tapered expander can go from .308 to .375 in one pass. It should work for you also.

[MUSTANG]

Do you have any reloading dies that aren in the .26 to .285 range? Examples would be 6.5 creed more, 6.5x55, 7x57 etc...

On a standard reloading press use a shell holder for the 5.7 case (RCBS #45, Lee #15, etc..) Use the reloading die with decapping rod/neck expander in order to open up the neck of the 5.7 cases. Do this step before running the 5.7 cases through a sizing ring to bring them to ~307 for making bullet jackets. Then insert your lead core (the opened neck should allow the core to go in). Then swage the core & jackets, then through the pointing swage die.

At least that's the way I prepare my 5.7 cases to use for jackets in my Corbin .308 Swage dies. I do not push the neck open with a single stroke; rather I bump the neck top open, lift bump again, and again 3 to 4 times to open the neck using this technique. I do this to avoid crumpled/telescoped necks which can occur unless I do the "Bump Process" I mentioned.


I do NOT believe that the tapered expander mentioned by garagdsrus will accomplish what you want to do.

[clodhopper]

Most 7mmTCU resize dies came with a long tapered expander ball designed to neck up .223 brass to 7mm. I have used them, but the neck was too big, and had to be sized down.
Then I made this from a Dillion die body, the hollow expander allows the long rod to eject the worked case...............283855

[Soundguy]

Will a lee expander die not work?

[jdfoxinc]

Sinclairintl.com
Under reloading supplies case prep.

[MUSTANG]

Will a lee expander die not work?

The Lee Expander dies are basically two different "Cone Angles".

283860

The slim expander will still dramatically expand the Mouth area of the 5.7 case - compared to the area where the existing neck area meets the body of the 5.7 Case.

283861

Using a 6.5 creed more, 6.5 x 55, 7 x 57, etc.. will result in an expanded neck that has the wall of the neck area "Straight", not dramatically belled. Excessive belling of the neck area will often result in the neck area splitting, then the jacket can not be used at the total length for making a jacket bullet (you could cut out the split area and use for a shorter/lighter weight bullet jacket).

[Soundguy]

Too bad you don't have a blank Barrel and just fire form it.

[clodhopper]

My die with the internal ejector was built because cases often had rim damage from using the shell holder to pull the case off the expander.

[MUSTANG]

I also use a Corbin (Top Punch) "E" Punch ; .290 inches in diameter, in order to open up the mouth of 5.7x28 when making jackets on my Corbin S-Press.

[garandsrus]

I do NOT believe that the tapered expander mentioned by garagdsrus will accomplish what you want to do.

Why not? The tapered expander also has a straight section so the entire neck can be expanded to the necessary diameter. If you will test it, I will make a tapered punch for you or the OP. Let me know what die body you will use to hold the punch.

[MUSTANG]

Why not? The tapered expander also has a straight section so the entire neck can be expanded to the necessary diameter. If you will test it, I will make a tapered punch for you or the OP. Let me know what die body you will use to hold the punch.

My comment is based on the Lee Expander being a "Cone". If one expands the mouth area to the desired diameter; then below the mouth is too small for the lead core to be inserted. If one expands the entire neck to where the junction with the neck and body are wide enough to allow the core to be exerted - then the mouth is "Too Wide" or at risk of splitting.

In the case off the "E" die I mention in post #10 above; the die punch has a gently sloping area (similar to a boolit/bullet Ogive area) that tapers to the shaft body that has a maximum width; in the case of the punch I use for this application - the max diameter is .290. This allows expanding the mouth down to the shoulder - forming a new "Body" in the old mouth to shoulder area that is about the same size as the body of the old 5.7x28 case.

In essence the "Tapered Punch" mentioned by garandsrus is the equivalency of my "E" die punch.

[rockrat]

A 6.5 cal. lyman "m" die might work, but a 6.5 tcu size die might work.

[garandsrus]

Here is the expander I made to convert 30-30 brass to 375 Win, .308 to .375 with one stroke of the press. I haven’t lost any cases to splits, but it may happen at some point. Several other people have used this same style with similar results. You can see the marks on the tapered plug where the expanding starts and the final position of the case. The shell plate pulls the brass off the plug very easily.
284849

Going from .223 to .260 should work the same way.

[MUSTANG]

Yep - Concur. Your pic is similar to the Corbin "E" punch profile. I have limited out on Pic Space so can not publish (or link for some reason) to pics any more.