Has anyone out there necked 308 brass down to 6.5 (260 Rem)?

Have gone down as far as .243. What's your concern, if I may ask? roger

Barsche, my concern is this- do I need to do any neck reaming and di they change any case dimensions with the 260. I guess what I mean ia are there any technical things I should know? I have relaoded for years but I have only necked up 30/06 to 35 Whelen. I think the is some case neck thickening when necking down.

I shoot several 260s and prefer Winchester Brass over Remington in most instances...Winchester doesn't make 260 brass, so I use other brass sizes..

I do own a batch of 243s, so I don't neck 243 brass up ot 260....

I do not own a 708 or a 308... So I neck down Winchester brass from those two calibers for the 260s use...

7/08 necks down a little cleaner than 308... the 308 always gets a little hump all the way around bottom of the neck... I just run it thru the sizing die a second time and it eliminates the hump.. It will still chamber just fine either way in all three of my 260s... 2 Rugers and one Remington VLS....

cheers
seafire

It will depend on the brass you use and the dimensions of the neck in your chamber. Just go ahead a neck a case down, seat a bullet, and
then measure the diameter of the neck with the bullet seated. Compare this to the neck dimension of your chamber and you should have at least 2 thousands clearance. You could also meaure a factory 260 Rem round to find out an acceptable dimension assuming your chamber is at SAAMI specs.

I had a heck of a time necking down, finally had to get a 7mm neck die then down to 6.5. It just kept folding the neck. No problem w/ 7-08 to 6.5 or .243 up. I don't have a .243 so just neck up exc. Lapua .243 to .260ai.

only real problem i have ever come across is the above mentioned ridge where the neck and shoulder meet. it goes away when you fire form.

I have a 6.5JDJ#2 in a Contender, which is based on the 307 Winchester. The 308 and 307 are the same using the exact same dies, the only difference is the rim. The 307 is rimmed and has a thicker base(web). I've made over 400 cases with "0" loss. I start by running the 307 thru a full-lenght 308 die to straighten out the neck and the rest of the case. Then I run it thru a 7-08 neck die. And last thru my 6.5JDJ#2 die to get proper lock-up in my Contender. The 6.5JDJ#2 is basically a 260Imp only using 307 brass which safely handles the pressure better than 308 brass. The only step left is fireforming to blow out the shoulder which I put 10gr of H4227(any pistol powder will do) and filling up case with Cream of Wheat and firing. Works well!! Also using virgin brass really makes life alot easier with this process.

I strongly advise against using 243 brass. Did a whole heap up to 7mm08 and had problems with necks breaking while loading from the magazine. The brass is weak at the 243 neck/shoulder joint. No problems with necking down as others have pointed out.

GK:

Sounds like to me that you had bad brass....

In OZ, was that PMC or something along those lines????or S&B?

Good Winchester, Remington, Lapua brass shouldn't do that on ya...

cheers
seafire

I've done it. First I necked to .270 then to 6.5 with the bullet sizing plug without the decapping pin, next I neck reamed to .264, as the neck was to thick to chamber freely, I then annealed the necks ( standing them up in a baking pan with about an inch of water heating the neck to dull cherry red and then tipping them into the water). once dried I proceeded to load and fire as normal. Did this back in the late "60s". there was no .260 rem then I called it the 6.5 X .308
Mike

PS forgot to mention that this was done to military surplus brass.
Mike

Got everything including ring at base of neck, followed just about everyone's suggestions but I cannot chamber a round in my grandson's Model 7 Rem. Hope the back ordered bras gets hete soon. Anyone have any new ideas?

Go for the necking up of .243 cases. I have a set of 47 necked up .243 to .260 & fireformed to the .260ai. I have (11) firings to date of full power loads & not a single case failure & I have only trimmed them once. The cases are all RP or Lapua, sorry GK, something is definetly wrong w/ the brass you are using.

Before the .260 made it to commercial status, I formed bunches of brass for a couple of 6.5x.308s using WW, Remington and IMI Match .308 brass. I preferred the Remington brass as it had slightly thinner necks, but I had no problems with any of the other brass, either. Later on, I just used Lapua.

Perhaps the dies I used played a part in the outcome. At that time, the dies had to be custom ordered from RCBS and weren't a mass-produced item.

Midway shows 260 Rem brass in stock $23.99 per 100.

Lyle