forming .260 brass from .308

[stebbins243]

Has anyone done this? I cant find any 260 brass from local shops and have a surplus of .308. I ran some thru the redding 260 dies and it looks like the shoulder is low. Would these need to fireformed with COW or would a loaded round be ok? Ive done both with my ackley and had good results both ways. But im unsure as to the lower head spce im getting with just cold forming.

 

[nhm16]

I haven't tried it but I would think you might need to turn the necks just because of how thick they are. Also the neck might be shorter than SAAMI. The short headspace will take care of itself first time you shoot it you fireform with a hard jam.

I would hold out for Rem. or Lapua .260 brass (my Remington brass has been very decent and has lasted 6 firings so far with one trip through the annealer). If you must form brass it would be easier to start withi 7mm-08 brass (no turning required) or .243 Win. brass (have to turn to take out donut).

 

[mao0720]

The head space should be the same but the only way to find out is to use a hornady headspace gauge. The only reason you would need to turn the necks is if they needed to be uniformed. You might consider doing an intermediate neck down to 7mm before going all the way down to 6.5mm.

 

[brian427cobra]

308 brass is .020 too short for 260, it's your chamber though, I recommend and use Win 7-08 or Win 243, I also neck turn, after fire forming the Win 7-08 and Win 243 are interchangeable, and shoot extremely well

 

[glbpmc]

I have used both Hornaday and Winchester brass.Just full length size and run. I have several friends and we have done this with several hundreds of these. Some have been through 10 varmint trips and work great.

 

[mytwo60]

Yes, I have done it. If you are using Lapua 308 brass then you'll need to turn the necks for sure. You can turn it before you size or after. Do a few to make sure everything fits before doing volume.

It's best to size down to 7mm before going to 6.5mm. Or what you can do is size it w/o the bushing first. Don't use anything smaller than .292 bushing. It will size down to .291 or even smaller.

Cool thing is you can play with the neck turning to see what is the most accurate for your chamber (ie .291, .293, .294 necks).

You'll get a small ring around the base of the neck that "might" be a little sticky chambering but once fired it will be gone.

 

[savagedasher]

Powder valley has 260 Remington in Lapua brass .My self I like necking up. Good Shooting Larry

 

[stebbins243]

thanks guys, i didnt even think of .243, i have that in surplus too, but a lot of lapua. I was thinking .308 cause of the amount i have. Ive sized a few and did have to turn the necks. this will get me thru the week until my order comes in.

 

[yenak]

Plus 1 on the 7mm/08. That's all i've used.

 

[kelbro]

308 works great. Length comes up only .010 short after two firings. No neck turning issue for me.

Others may be 'better' but I had a lot of really consistent weight and straight LC Match brass in 308 and it does not have any caliber markings on it. I worry about 'mis-marked' brass.

 

[BradY]

I have run 308 palma down to 7mm then 260, neckturned then fireformed to 260 improved and its worked very well. H4350 works great, but H4381sc seemed to have ignition problems with the small magnum primers. I was getting 10-15 good shots then one or two low. Chronograph said the same. In the end I gave up and went back to H4350 and its been great. I would probably go the large primer cases next time and not bother necking down and turning.

 

[ratguner]

308 brass is .020 too short for 260, it's your chamber though, I recommend and use Win 7-08 or Win 243, I also neck turn, after fire forming the Win 7-08 and Win 243 are interchangeable, and shoot extremely well

Isnt that where the 6.5-08 came from?

 

[Hoser]

I use Lake City 7.62 LR brass necked down. I had my chamber cut specifically for the slightly thicker necks. Works perfect and no neck turning.