Forming .260 from .243 Brass

Uncle Norm

Well-Known Member
In anticipation of my new .260 that James (jagerSA) is doing for me, I bought a new set of Redding .260Rem dies.
I had sought some advice from one of our members so didn't anticipate any problems with forming some of my Norma .243 cases into .260Rem.

I got five .243 cases that had not been touched since being last fired, cleaned, flared the mouth and lubricated the case and the inside of the neck.
The .260 FL length die would not enter the neck without using excessive force :(.

So I removed the stem and looked at the expander ball. I noticed that the leading edge of the Redding expander ball has a knurled section to enable it to be tightened onto the rod that holds the de-capping pin. This knurled section was binding fiercely on the mouth of the .243 case and there was no way that it would enter and pass through to reform the neck.

Whilst I am an experienced home loader, I have never formed brass from one cartridge into another.

So it looks like Murphy's Law has struck and I have got the wrong dies for this particular job. One of our members has advised that he has no problem in reforming .243 to .260 using RCBS dies but I don't fancy the additional expense of buying another set of dies.

Perhaps I need to forget this idea and buy a hundred Lapua .260Rem cases ? Anyone got any better ideas or even some .260Rem brass for sale ?
 
I do this operation quite a bit. Some brands of die achieve this better than others, notably Lyman and Lee..... RCBS aren't good either.

You need a 'Tapered Expander Ball' which Redding do as an accessory part. Norman Clark is your man.

ATB.
 
Or, you could order a Lee 7mm-08 FL die and begin with 308, running them through the 7-08 die as an intermediary step. ~Muir
 
Didn't think about neck turning-reaming capabilities: I kind of take such things for granted. My buddy reforms 243 to 6.5 Creedmore for the same reasons.~Muir
 
That's messy, and forms a donut .... have tried it. The necks on the product are too thick too.

Here's a link .........

Tapered Size Buttons | Redding Reloading Equipment: reloading equipment for rifles, handguns, pistols, revolvers and SAECO bullet casting equipment

Thank you for this Sinistral, very helpful. I have e-mailed Redding as I have enjoyed excellent customer service from them in the past. I will also try Norman Clarke.
I have learned something as I was not aware that tapered expander balls existed.
 
All you need is a 6.5mm expander mandrel. I have one to make 7mm brass from .243. It's either a Redding of a Forster product. It wasn't expensive. You could go in the other direction, neck .308 down to .260. Again, I've done that for my 7-08, and this time I use a 7mm reamer to ensure the neck walls aren't too thick. And again it's either a Redding of a Forster product. I probably bought the expander and teh reamer from Sinclair International (which is now owned by Brownells).

-JMS
 
All you need is a 6.5mm expander mandrel. I have one to make 7mm brass from .243. It's either a Redding of a Forster product. It wasn't expensive. You could go in the other direction, neck .308 down to .260. Again, I've done that for my 7-08, and this time I use a 7mm reamer to ensure the neck walls aren't too thick. And again it's either a Redding of a Forster product. I probably bought the expander and teh reamer from Sinclair International (which is now owned by Brownells).

-JMS

Thank you JMS. Is a mandrel a different item to the tapered expander ball ? If so, could you post a product reference number or similar please ?
I have a good stock of once fired Norma and Federal .243 cases and have no experience of neck reaming, so will go .243 to .260.
 
Buy the lapua 260 brass and save all the messing.if you get 8 shots per case there a bargain.i would 100 percent

Its certainly an option. I enjoy all the 'messing' though. Its part of the enjoyment of reloading. A bit like tying one's own trout flies; until you stick a hook through your finger.
 
I like tinkering with it too but buying new is much more appealing to me, I would rather spend the money on trying different bullets or powder norm
 
Uncle Norm,

With the right kit necking up is such a simple operation. It's much more complicated to squeeze down as there is excess brass to force downwards, and remove afterwards. Expanding the neck of a fired .243 case to .260 should be a snap. If not then an intermediate useful step would be to use a standard .25/06 die expander ball to halve the effort, and reduce the chance of a 'cocked' neck where excessive force buckles the tension built into the neck/shoulder junction.

Ownership of Redding dies seems to be the holy grail of reloading endeavour on SD, but at the lower end of the range they are not all that special. In fact the whole product line is designed to complement one another to tie you to the brand. They aren't interchangeable with other marques either, whereas you can swap parts between RCBS and Lyman if you've got Dies in each.

IF a Redding Tapered Sizer can't be found, before trying anything too radical or laying out even more cash I'd suggest incremental expansion - 243" to .257" then .264". In fact I'm talking balls - successively switching 'expander balls' but using a type which isn't knurled like the Redding series.

I've got a dozen or so sets of different calibre Dies in Lyman & RCBS in the 6mm, .25, and 6.5mm size which might work a treat. Probably the best product on the market is the LEE 'Eez-ee' expanding stem fitted to late Lee dies, but I don't have LEE in .260 although almost everything else. I'm only a few miles from you if you're still stuck with the Redding sizer.
 
I would defintiely better to use the proper expanded ball from Sinclair and size up the 243's. It is an absolute win-win when you can utilize something nearly useless to amie something of value.

SS
 
I would defintiely better to use the proper expanded ball from Sinclair and size up the 243's. It is an absolute win-win when you can utilize something nearly useless to amie something of value.

SS
+1. http://www.sinclairintl.com/reloadi...ir-generation-ii-expander-dies-prod38807.aspx are excellent for this type of operation.

However, given the ready availability of Nosler, Lapua and Remington 260 Rem brass, I'm not really sure of the benefits of what you are attempting.

Regards

JCS
 
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A straight neck-up of 243 brass almost invariably produces a 'doughnut' (internal ring) just above the case-neck / shoulder junction. That's because the 'old' 243 case junction moves into the 260 neck section. There's no problem with this if your 260 Rem loads are such that the bullet shank remains above the 'doughnut', but it's an accuracy wrecker if you push the bullet through it. It's easy to tell if you suffer from the problem, the extra pressure needed being easily felt on the press handlw during bullet seating.

The answers are: 1) get a 6.5mm inside neck-reamer and remove the doughnut after the first two firings in 260 form; 2) neck 308 brass down rather than 243 up; 3) the sensible option as already recommended - buy Lapua 260 Rem brass.
 
A straight neck-up of 243 brass almost invariably produces a 'doughnut' (internal ring) just above the case-neck / shoulder junction. That's because the 'old' 243 case junction moves into the 260 neck section. There's no problem with this if your 260 Rem loads are such that the bullet shank remains above the 'doughnut', but it's an accuracy wrecker if you push the bullet through it. It's easy to tell if you suffer from the problem, the extra pressure needed being easily felt on the press handlw during bullet seating.

The answers are: 1) get a 6.5mm inside neck-reamer and remove the doughnut after the first two firings in 260 form; 2) neck 308 brass down rather than 243 up; 3) the sensible option as already recommended - buy Lapua 260 Rem brass.
what would you know anyway :D Lmao ;) .listen to this man, he has forgot more than most of us know :-|:D
 
How about saving money? There are other methods of achieving this, and recycling is now in vogue.

I'm lost. I don't see any connection between necking up 243 Win brass to 260 Rem, apart from driving up sales of powder, primers and bullets. For a quality performance from a quality rifle, use the best brass available off the shelf (Lapua 260 Rem).

Regards

JCS
 
I've got a stack of 260 brass, it's easy to find lately. Brock and Norris is the best place to go. I honestly wouldn't bother necking up 243 brass. I bought a bag of 100 remmington brass for 55, and recently bought a box of 100 lapua and split it with my mate. The quality of the lapua is fantastic in comparison but the remmington does the job well.
 
Thank you JMS. Is a mandrel a different item to the tapered expander ball ? If so, could you post a product reference number or similar please ?
I have a good stock of once fired Norma and Federal .243 cases and have no experience of neck reaming, so will go .243 to .260.

The expander ball is for use on 6.5mm brass, not for necking up .243 brass. Necking up is straightforward. Just lubricate the inside of the case neck first (you can use Lyman's dry mica or graphite powder - which is messy buy dry).

Expander Mandrels and Neck Tension within AccurateShooter.com
 
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