Turn .308 winchester to 6.5 Creedmoor

[machinest-man]

Can anybody give me direction to take .308 Win cases to convert then to 6.5 Creedmoor.

[EDG]

All you have to do is try a few things that you think might work.
Some things will work and some won't.

1. Size once fired brass in a .308 FL die
2. Size in a 7/08 FL die
3. Size in a 6.5 Creedmoor trim die
4. Cut off or trim in a 6.5 Creedmoor trim die
5. FL size in a 6.5 Creedmoor FL die.
6. You might need to anneal your necks some where in this process depending on how hard your once fired brass is.

You have to be willing to experiment and kill a few (or a lot of) cases developing your forming process.
I would recommend that you start with some cull cases or the almost worthless Nato berdan primed cases that are often found discarded at the range.

[Rainier]

FWIW I’ve turned many 308 cases into 6.5 CM. I size and deprime in the 308 die then, after the judicious application of Mobil 1 motor oil for lube, make a pass into the 6.5 CM sizing die with the expander/deprimer rod and securing nut removed. Next, trim them to length and size them a second time with the expander reinstalled. I also made sure to anneal them because of the distance your moving the shoulder and pay attention to case neck size, some of the brass may be too thick and need the necks turned.

I did find that Winchester brass is too soft and it just crushes the shoulder. Military brass (Think LC), FC, Hornady and PMC all worked great. BUT... the easiest and most consistent brass to work with is the Black Hills 308 Match - no neck turning with consistent water weights when done.

Good luck with your project!

[Blitzfike]

I've been reforming brass for 6.5CM for about two years. I find that annealing first results in way more lost cases. Working with EDG's process of using a 7mm08 die as an intrim stage works pretty well for me. I also found that military brass works best as far as not collapsing during reforming. I have to turn almost all the necks after forming. Check water grain capacity of mil brass afterward and adjust your loads by the percentage difference of case capacity. Being old and not completely broke, I buy CM brass when and if I can find it on sale just to forgo all the work in converting the 308 brass I also shoot.

[country gent]

If your having issues with pushing the shoulder back when finish sizing a way around it would be to dedicate a 308 sizing die to this and face the bottom down then re cut the mouth radius and push the shoulder back when doing the first initial sizing on the case keeping the original neck dia may allow it to flow and form better.

I havent looked to see the difference in angle and head space. but subtracting the 6.5 CM head space from .308 will give an idea how much to remove from bottom of die.

Adds a step to the process but may allow commercial Brass to be used. Buy cutting a die down the CM die and final sizing die only has to re angle the shoulder and a little neck work.

[PWS]

I did a batch of PMC .308 brass and lost maybe one out of ten going straight to 6.5 in a standard RCBS FL sizer with RCBS Lube. There was a fine line between too much lube and oil denting vs. not enough and collapsing the shoulder. Ended up needing to turn down the neck wall thickness so question whether it was worth the time it took to do the conversion.

[country gent]

I have sized down 308s to 243 strickly for the reason of being able to fit the necks on a couple rifles. Improved accuracy some and made them last longer. ALso saved having a xustom chamber cut and new barrel. I turned to .001 clearance total. It helped a lot went from 3/4 min rifle to bug holes at 100 yds. being able to fit the necks can make a difference. Bevch resters shooting fitted necks will wear a barrel out with 20 cases.