First attempts at resizing .308 to .260, suggestions needed

H

hounddawg

New member
I am phasing out of .308 reloading and in the next range session sending the last of my loaded .308 to the great berm in the sky.

I will be rebarreling my last .308 to .260 Remington which will leave me with 300 hundred + .308 cases and no guns to shoot them in. They are mostly Lapua with a few Hornady's . Some of the Lapua are a bit long in the tooth with almost 20 reloadings. The Hornady and 100 of the Lapua have less than 10

I have the following dies available to do this with.

A Redding .260 body die, RCBS full length X die, Lee full length sizing die, and Lee collet neck die. I have the tools to trim and turn the necks if necessary along with plenty of imperial sizing wax on hand.

I am wondering if it is even a good idea since I will keep both the small shank barrel and still have a large shank Savage .308 bull barrel sitting in the corner. All suggestions or hints are welcome since I have never attempted anything like this.
 
Those necks have been work hardened . If you have the means to neck anneal,
It would be a good plan.
Beware poorly done neck annealing might ruin the brass.
I would not be afraid to try just lube and size the .308 down in a conventional .260 sizing die if it was virgin or annealed. If it wrinkles,try finding a basic Lee 7-08 sizing die for an intermediate step.

I can't tell you how much your necks will thicken. You may need to turn or ream.

I understand Lapua brass is a cut above. Given you have 10 to 20 loads through them already,they don't owe you much.

If .260 is hard to find,I think Starline is making it. Its not Lapua,but its brass.
 
Thanks HiBC. I anneal after every firing using a modded Annealeeze. I forgot to mention I also have a Wilson neck reamer.

I have between one hundred and 200 .260 Lapua's so it is not really a question of need. Some developed loose primer pockets and I discarded them and picked up 50 Starline to see how they held up. The Starlines are on their 5th reload now and so far seem to be good brass.

back to the resizeing I think I will give a few Hornadys a fresh anneal and try the RCBS X dies first
 
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Basically I would say you are necking the case down, there is .002" difference in the length of the case from the case body/shoulder juncture to the case head. I would believe it a bad habit to jump in and size all of the cases before you determined the length of the chamber from the shoulder to the bolt face.

Part of the neck will become part of the shoulder after ne4cking down.

F. Guffey
 
well here are the first three attempts using the Hornady cases.

The first case was resized with the RCBS .260 full size die that was set for a .002 shoulder bump. The second I resized using a Lee .308 die first then the .260 die followed by the neck size die, the third I turned the neck to .010 thickness and then used the .260 full size die. It seems to have the least prominent bump located at the junction of the neck and shoulder The bump is only on the outside of the case as near as I can tell by using a paper clip to feel the inside of the case. I did not even bother to check to see if they would chamber, they are now in the recycle can

I have decided this was a bad idea and will just load some of the cases with some leftover Hornady 178 ELDX's and send em to my son in law for hunting ammo


edit was looking at the SAAMI specs and the .260 Rem has a OAL of 2.035 and the .308 has a OAL of 2.015. Not sure if that would have anything to do with it.
m0qe84M.jpg
 
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I have an MOA Maximum singleshot handgun in .260 Rem. Extraction on the rimless cartridge is ,in my experience,marginal.
Idea!! I saw a bag of .307 Win brass and bought it.. Virgin,I ran a few through a .260 size die.It straight forward sized just fine.I set the project aside...but it will work.
 
I believe you failed to have the die screwed down to the shell holder, in the perfect world there is .002" difference in the length of the 2 cases from the case body/shoulder juncture to the case head. Both chambers have the same 20 degree shoulder and according to some literature the 260 case is .10" longer from the mouth of the case to the case head. Again, you are necking the case neck down, necking the case neck down will increase the length of the case from the from mouth the neck to the case head.

F. Guffey
 
Well I got one to form more or less. I started with the die about 1/8th inch from the shell holder then gradually worked it down to where it touched in about 4 steps. Shoulder looks a bit weird, almost like the extra metal went there.works for them.

The case grew in length about .007 and was .002 thicker than unmodified cases with a small bump which looks like extra metal about 1/2 way up the shoulder

https://imgur.com/a/Rrvwi


It chambered ok so I seated a bullet and it still chambered smooth as glass. That being said I think I shall just let those .308's stay .308's Now if I run across some 243's up at the range I might scrounge them up and see if I can get them to neck up.

This was a good way to kill a couple of hours and learn a few things but as long as I can get real .260 cases that was all it will ever be. Thanks to all for the advice though, I appreciate the feedback
 
Do let us know how this works. I know that one can full length resize from .308" down to .277" but definitely not to .243". Is the extra .013" to go from .270 to .260 the deal breaker? The line must exist somewhere close to there. As has been said, annealing, using a 7-08 die first, and perhaps needing to turn the necks depending on your chamber. The necks will most definitely thicken.
 
I don't have a 7mm 08 die on hand, I may pick one up on Ebay sometime though. No rush there

I do have four 7 mm - 08 cases and I will try and resize them to .260 later. Every year during hunting season the hunters will leave boxes of fired cases on the benches at the range. I had picked 10 up to try and make some home made dippers out of and had these left over. I will post the results later
 
7-08 cases work perfectly to go to .260 and necking up .243 cases work too. My experience has been .308 cases make a "doughnut" and the necks become too thick to chamber in my rifle.

If it were me I'd sell or trade the .308 cases for 7-08 or .243 cases...I'd try to trade for regular .260 cases but I doubt you'll be able to trade for them.
 
I have loaded a lot of 308, military and commercial, straight down to 243 with no problem. Doing the 260 should be even easier. Don't neck size the first time. FL, raise the ram and screw to die down right on top of it. And I never have had to turn necks but there will likely be a bit of trimming. After the first firing, you can then neck size.
 
Well for whatever reason the Federal 7mm - 08's would not work either, to be fair I did not anneal first so that may be the reason. Used the RCBS full length X die screwed down to the case holder on the first one and collapsed the shoulder , the second I tried sneaking up on it and doing it in stages and ended up with the donut of extra metal.

maybe I am just not holding my tongue correctly or the reloading gods are mad at me but I have gave up on this experiment. Thanks again to everyone for all for the help and suggestions but for me this isn't meant to be.
 
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