Generally the commercial ammo manufacturers don't engineer their cases to give long case life. Generally commercial brass has very short life from the primer pockets opening up. Thus if you keep reloading them you will get gas leakage around primer that will cut a groove in your bolt face. I have used commercial brass that was so poorly made some primers fell out when bolt was opened on first firing. Other brands are generally good for two to 8 reloads.
6.5 Creedmoor cases can be made from 308 cases and the toughest I have found is surplus M118 Match Cases and IMI (Isaeli Military Industries). 7.62 ball brass can also be used if you remove primer crimp. I have personally reloaded M118 cases (made by Lake City Army Ammunition Plant) over 90 times and they were still going.
Converting these cases can be time consuming and require prep procedures you don't normally use in reloading but it can be done. Below is the best I have come up with:
1. Take once fired LC Match cases or IMI cases and full length resize them.
2. Using a neck turning tool adjusted to cut the necks to .013" neck wall thickness.
3. Run them through a 7/08 FL die with the decap rod removed to reduce neck diameter.
4. Run them through a 260 FL die with decap rod removed.making the necks smaller.
5. Trim the cases to the correct length.( they need to be shortened to the SAAMI Creedmoor Drawing spec.
6.. Measure the neck wall thickness to see if they are still .013" thick.
7. Stress relieve neck and shoulders.
The next is tedius but worth the effort. when you size the cases using a 6.5 CDM body die and 6.5 Creedmoor die. You will need to take multiple passes bumping the shoulder and slowly bump the shoulder back to where it will go in a Wilson 6.5 Creedmoor Case Gage.
Why turn them to .013" wall thickness? THe M118/IMI necks are much thicker than CDM necks and you need to duplicate the 6.5 CDM SAAMI Drawing. If you turn the neck walls to .013 thickness you have same distance on both sides.Insert a .264 diameter bullet and you should have a loaded round measuring ..290" outside neck diameter. The SAAMI Drawing calls for a max loaded case neck of .295".
MILSPEC Match brass neck wall thickness can vary .005" and still be in spec.which means your bullet is offset in neck ..005 from the bore center line. so when you pull the trigger the bullet moves forward into throat and contacts one side first deforming your bullet. Bench rest shooter's chambers generally run only .001" larger than loaded round.
You will spend about 5 hours making 50 rounds but you will have cases that will last a very long time.
UPDATE: Just made a very interesting discovery that works great and allows 6.5 CDM cases to be made much faster.
If you have a lathe and a 308 Win Finish chamber reamer you are good to go.
I made up a sizing die from 1" diameter cold rolled steel and it works much better than body die I bought as the 308 shoulder is smaller to start with than the body die will make it later
I took a piece 3 1/2" long and I drilled a 5/16" hole all the way through it.
Next I turned it down and threaded it 7/8 X 14 for two inches to go in standard loading press.
Next I ran a 308 chamber reamer in and stopped so that a 308 case would stick out the back about ..500 to .525 and you can locate the shoulder exactly where you want it.
I pre trimmed 308 cases to 6.5 CDM length.
I then run the cases into the 6.5 CDM die and set the shoulder back till the shoulder locates the same place a 6.5 Creedmoor case needs to be.
Push in/remove 308 case pre trimmed to 6.5 CDM Die with loading press.
You will need to expand the neck back out to thin down the neck wall.
Turn neck wall to .013"/.014" thickness. Chamfer case mouth.
Made an expander from .311 oil hardening drill rod about 1 1/2" long. Turn one end down to .262 and .265 on the upper end, heat it to red hot and drop in oil. It will hold nicely in a 30 cal collet in your bullet puller to open the neck.
Case should fit perfectly in L E Wilson Creedmoor Case Gauge and have no dimples/creases etc.
Theoretically you could cut the bottom off a 308 FL die off about .500=.525 and it might be possible with to do it with a 308 seat die cut off the same way.
Took about two hours to make die from scratch.
The shoulder die I got would not size outside of shoulder enough to go in chamber. With the one I made up it sizes exactly where I need it with much less work. I estimate I can rework 50 308 cases in 1/4th the time it took using 6.5 Dies and the Shoulder die when I fireform them.
UPDATE: Found 50 LC 81 M118 cases that had been fired and tumble cleaned so I decided to time a batch.
Trimmed cases to 6.5 CDM length 17 Min 8 seconds
Set back shoulder with my die 4 Min 58 seconds
Finished setting back shoulder with FL CDM die 6 M 41 seconds.
Expand the necks to turn neck was to .013 thickness 6 Min 13 seconds.
Max neck diameter on SAAMI drawing is .295 so I may a adjust my Neck tool to cut them a tad thicker and get up to 2.294 or .295
(I just changed my neck turning tool to have .014 neckwall thickness.
Obviously the above work hardens the necks/shoulder are so I will have to tumble clean them and anneal the neck/shoulder area. The neck turning would have gone much faster had I washed the cases and annealed them before I started to neck turn.
6.5 Creedmoor cases can be made from 308 cases and the toughest I have found is surplus M118 Match Cases and IMI (Isaeli Military Industries). 7.62 ball brass can also be used if you remove primer crimp. I have personally reloaded M118 cases (made by Lake City Army Ammunition Plant) over 90 times and they were still going.
Converting these cases can be time consuming and require prep procedures you don't normally use in reloading but it can be done. Below is the best I have come up with:
1. Take once fired LC Match cases or IMI cases and full length resize them.
2. Using a neck turning tool adjusted to cut the necks to .013" neck wall thickness.
3. Run them through a 7/08 FL die with the decap rod removed to reduce neck diameter.
4. Run them through a 260 FL die with decap rod removed.making the necks smaller.
5. Trim the cases to the correct length.( they need to be shortened to the SAAMI Creedmoor Drawing spec.
6.. Measure the neck wall thickness to see if they are still .013" thick.
7. Stress relieve neck and shoulders.
The next is tedius but worth the effort. when you size the cases using a 6.5 CDM body die and 6.5 Creedmoor die. You will need to take multiple passes bumping the shoulder and slowly bump the shoulder back to where it will go in a Wilson 6.5 Creedmoor Case Gage.
Why turn them to .013" wall thickness? THe M118/IMI necks are much thicker than CDM necks and you need to duplicate the 6.5 CDM SAAMI Drawing. If you turn the neck walls to .013 thickness you have same distance on both sides.Insert a .264 diameter bullet and you should have a loaded round measuring ..290" outside neck diameter. The SAAMI Drawing calls for a max loaded case neck of .295".
MILSPEC Match brass neck wall thickness can vary .005" and still be in spec.which means your bullet is offset in neck ..005 from the bore center line. so when you pull the trigger the bullet moves forward into throat and contacts one side first deforming your bullet. Bench rest shooter's chambers generally run only .001" larger than loaded round.
You will spend about 5 hours making 50 rounds but you will have cases that will last a very long time.
UPDATE: Just made a very interesting discovery that works great and allows 6.5 CDM cases to be made much faster.
If you have a lathe and a 308 Win Finish chamber reamer you are good to go.
I made up a sizing die from 1" diameter cold rolled steel and it works much better than body die I bought as the 308 shoulder is smaller to start with than the body die will make it later
I took a piece 3 1/2" long and I drilled a 5/16" hole all the way through it.
Next I turned it down and threaded it 7/8 X 14 for two inches to go in standard loading press.
Next I ran a 308 chamber reamer in and stopped so that a 308 case would stick out the back about ..500 to .525 and you can locate the shoulder exactly where you want it.
I pre trimmed 308 cases to 6.5 CDM length.
I then run the cases into the 6.5 CDM die and set the shoulder back till the shoulder locates the same place a 6.5 Creedmoor case needs to be.
Push in/remove 308 case pre trimmed to 6.5 CDM Die with loading press.
You will need to expand the neck back out to thin down the neck wall.
Turn neck wall to .013"/.014" thickness. Chamfer case mouth.
Made an expander from .311 oil hardening drill rod about 1 1/2" long. Turn one end down to .262 and .265 on the upper end, heat it to red hot and drop in oil. It will hold nicely in a 30 cal collet in your bullet puller to open the neck.
Case should fit perfectly in L E Wilson Creedmoor Case Gauge and have no dimples/creases etc.
Theoretically you could cut the bottom off a 308 FL die off about .500=.525 and it might be possible with to do it with a 308 seat die cut off the same way.
Took about two hours to make die from scratch.
The shoulder die I got would not size outside of shoulder enough to go in chamber. With the one I made up it sizes exactly where I need it with much less work. I estimate I can rework 50 308 cases in 1/4th the time it took using 6.5 Dies and the Shoulder die when I fireform them.
UPDATE: Found 50 LC 81 M118 cases that had been fired and tumble cleaned so I decided to time a batch.
Trimmed cases to 6.5 CDM length 17 Min 8 seconds
Set back shoulder with my die 4 Min 58 seconds
Finished setting back shoulder with FL CDM die 6 M 41 seconds.
Expand the necks to turn neck was to .013 thickness 6 Min 13 seconds.
Max neck diameter on SAAMI drawing is .295 so I may a adjust my Neck tool to cut them a tad thicker and get up to 2.294 or .295
(I just changed my neck turning tool to have .014 neckwall thickness.
Obviously the above work hardens the necks/shoulder are so I will have to tumble clean them and anneal the neck/shoulder area. The neck turning would have gone much faster had I washed the cases and annealed them before I started to neck turn.
