6.5 CM fail

[cowboybart]

Second time out with the 6.5CM that was cobbled together from parts. The first time resulted in 2 shots touching and the other 3 making a 6" group. This time was similar with a new kink - separated cases
The cases separated about 3/8"-1/2" above the rim. I suspected excessive headspace and stopped shooting that rifle. Once home I checked: the NO GO gauge allows the bolt to close only about an 1/8". The bolt closes on a GO gauge. Either I have bad gauges, a short chambered barrel that allows the barrel to seem to be in spec, but leaves the case unsupported, or ... ???
I have a depth mic and can measure how much of the GO gauge sticks out of the removed barrel, but I have nothing to compare it to.
I REALLY miss my 260!

[Robinhood]

You are over-sizing your brass. It is stretching causing Case Head Separation. Do you have a case head space measuring tool? If you do check to see if your cases are longer than your gauge.

[Robinhood]

Also, whatever you measure for your gauge protruding from the breech it should be .010 to .015 longer than the depth of the boltface.

[Stumpkiller]

Much as I like my .260 Rem Savage I don't think you can blame case separation on the 6.5 Creedmore. 50 fps less all else equal but not separation. ;-) That would be a excess headspace.

Do you have a comparator? May be time to get one.

[cowboybart]

You are over-sizing your brass. It is stretching causing Case Head Separation. Do you have a case head space measuring tool? If you do check to see if your cases are longer than your gauge.

The brass is twice fired. Once in a buddies rifle, then FL sized in a Hornady die, then in my rifle. What is this tool? A Wilson case gauge?? A bullet comparitor and use it in the shoulder??

[Robinhood]

It is a tool that helps measure the distance from the base of the case to the datum on the shoulder of the case. Your cases should be sized to a length of the head space minus .002". Chances you will not know the exact headspace unless you are able to fire the cartridge without the primers backing out. Obviously if the primers are backing out or you are having head separation your brass is being "over" sized meaning it is sized to short for the chamber.
https://zimbi.co.za/wp-content/uploads/2017/02/Comparator.jpg

A Wilson tool will tell you if it falls within tolerance but will not give you numbers to compare with.

The first thing you should test if you are left scratching your head is the gauge protrusion from your head. I was thinking that on a savage it is between .125" and .130. I cant remember but I know that is real close. The counter bore on your factory bolt head should be between .115" and .118" that should give you at least .010 clearance between the end of the bolt head and the face of the barrel breach. If you get something slightly different you shouldn't worry about it as long as those faces do not touch.

[J.Baker]

https://www.savageshooters.com/content.php?322-Barrel-Chamber-Depth-Verification

[LoneWolf]

Brass from other rifles even if FL Sized always needs formed to a new rifle. It often leads to issues due to different chamber specs. Gets some virgin brass or factory ammo and save the cases. Second, what load did you use that you had case separation. None of what you're experiencing is because of it being a 6.5 Creedmoor. Improper loading and ammo out of spec for the rifle sound to be the issue.

[mnbogboy2]

Second time out with the 6.5CM that was cobbled together from parts. The first time resulted in 2 shots touching and the other 3 making a 6" group. This time was similar with a new kink - separated cases
The cases separated about 3/8"-1/2" above the rim. I suspected excessive headspace and stopped shooting that rifle. Once home I checked: the NO GO gauge allows the bolt to close only about an 1/8". The bolt closes on a GO gauge. Either I have bad gauges, a short chambered barrel that allows the barrel to seem to be in spec, but leaves the case unsupported, or ... ???
I have a depth mic and can measure how much of the GO gauge sticks out of the removed barrel, but I have nothing to compare it to.
I REALLY miss my 260!

Most of us who have reloaded for a few years have gone through the same thing as you. When I started back in 1964 or 1965 we didn't have internet or forums like this one to learn from.
Every die manufacturer sends out a set of instructions with their dies. Most often it will tell the reader to run the die in so the shell holder touches it. Often this will work for the hand loader with no problem. Here is the rub; sometimes this method sizes the case down much shorter from shoulder to base than needed. Each subsequent firing again stretches the case back out to chamber dimensions. Sometimes this will cause the case to separate on only two or three firings.
Alternately we can adjust the die down just far enough to allow the sized case to chamber. This eliminates most of the stretching and case life will no longer be determined by headseparation. Other factors like loosening primer pockets or neck splits may then be the limiting factor.
I have got up to 35 loads on a 260 back in the day. Normal life for your Creedmoor should be at least 10. I have five 6.5 creeds and brass life is determined by the pockets with some brass brands far exceeding others.
I would suggest setting your FL die so you cannot chamber a sized case with one layer of "scotch" tape on the case head. The scotch tape is about .002 inch thick. This will greatly extend your case life.
The brass already two fired in the other rifle and FL resized may already be too late to save if thinning just above the web has already started.
Search for "paperclip test" to inspect the offending brass.
There is a lot to digest on this subject but don't give up on the Creedmoor just yet. My guess that setting the die to match your chamber will make a big difference in your results.

My .02,
Randy

[Robinhood]

^ Like

[sharpshooter]

It would seem to me that your resizing die is too short, or your shell holder too shallow. One way to check it, is to remove the the decap assembly, and drop the go gauge in and measure the protrusion. It should be .125", and the same for the depth of the shell holder. If the shell holder is shallow, you could try another brand, or use the Redding competition set that goes up to .010" deeper. If you need over .010" to get contact and get a .002" shoulder bump, you might have to do what I did on a few shell holders. I put 3 spots of weld on the shell holder, then ground them down to the correct height, so when they bottomed out on the die, it would only bump the shoulder .002".

[Stumpkiller]

One of the best bits of gear I have learned to use is a set of Redding Competition Shell Holders. There are five in the kit that are progressively deeper by 0.002". A standard die is inset 0.125". These are 0.0127" (+0.002"), 0.0129" (+0.004"), etc. You use a full length resize die but start (with fired brass) on the +0.010" die. If the case will not chamber, move to the +0.008" and try again. Repeat until the bolt closes freely, or even slightly snug. That is your minimal headspace and easily resettable because you can cam-over on the competition die instead of needing to leave a gap.

[Shooter0302]

[QUOTE=cowboybart;462429]The brass is twice fired. Once in a buddies rifle, then FL sized in a Hornady die, then in my rifle. What is this tool? A Wilson case gauge?? A bullet comparitor and use it in the shoulder??[/QUOTE

Why not start from scratch and buy some new brass,fire a few rounds, then see if the fired rounds will chamber back in the rifle, if they chamber ** then move on to what others have said.
While ordering your new brass, and since this is a bolt gun, order a Lee collet die, no dragging the expander ball back out the neck

[cowboybart]

This isn't my first day at the rodeo, I've been handloading since the mid '80's (don't let my profile age fool you - I never entered it and don't know how to change it). I use a bullet comparator but not a cartridge one. I can solve that.
Turns out that the barrel is goofed up from Savage. Upon inspection with a bore cam, it appears that a chip found its way onto the reamer flute and damaged the neck/shoulder junction. Somehow this was missed in their QC check - imagine that! No worries, I have a 6 CM reamer and will need a 6.5 pilot for it. I also have 6.5 neck and 6.5 throat reamers. I'll take .100" off the breech then deepen the chamber and try this barrel again.

I suspected an out of spec FL die and I will check that too - Thanx SharpShooter

Load was 42 grs of Big Game and a 120gr Sierra Game King in Nosler brass with a Fed primer. It was my starting load. The first 3 look normal, #4 had a ring on the bottom and #5 came apart.

[Robinhood]

This isn't my first day at the rodeo, I've been handloading since the mid '80's (don't let my profile age fool you - I never entered it and don't know how to change it).

So you were yanking our chain the whole time. Dastardly deed my brother.

[mnbogboy2]

This isn't my first day at the rodeo, I've been handloading since the mid '80's (don't let my profile age fool you - I never entered it and don't know how to change it). I use a bullet comparator but not a cartridge one. I can solve that.
Turns out that the barrel is goofed up from Savage. Upon inspection with a bore cam, it appears that a chip found its way onto the reamer flute and damaged the neck/shoulder junction. Somehow this was missed in their QC check - imagine that! No worries, I have a 6 CM reamer and will need a 6.5 pilot for it. I also have 6.5 neck and 6.5 throat reamers. I'll take .100" off the breech then deepen the chamber and try this barrel again.

I suspected an out of spec FL die and I will check that too - Thanx SharpShooter

Load was 42 grs of Big Game and a 120gr Sierra Game King in Nosler brass with a Fed primer. It was my starting load. The first 3 look normal, #4 had a ring on the bottom and #5 came apart.

Sounds like your gauges wouldn't chamber deep enough because of the damaged chamber. Glad you found it. I learned a good look with a bore camera or scope will tell you volumes. Funny you didn't notice it on the brass also.
Good luck with getting it percolating again.

[cowboybart]

Got it cleaned up with a neck and throat reamer, but now the throat has a good bit of free bore. I'm gonna swap it over to a Marlin XL-7 action but need to take .008" off of the breech to get it to headspace. In the long action I will be able to seat the bullets out further due to the long mag box.

[tobnpr]

Savages "catching a chip" aren't unheard of...

https://i.imgur.com/tlgtIU1l.jpg

Since you have a lathe and can set back, why didn't you face the breech back .050 and use a chamber reamer (if you don't have it, you can rent from 4D) to deepen to spec and clean it up?

[Quikshft]

This isn't my first day at the rodeo, I've been handloading since the mid '80's (don't let my profile age fool you - I never entered it and don't know how to change it).


I just noticed my age wasn't listed at all, so updated my profile. At the top of the page is a dark blue ribbon and three items have 'drop down menus'. Hit the 'Forum Actions' and you can choose 'edit profile'. You can enter your age near the top of that page. Youth is over-rated, with age comes the beauty of experience. :smug:

[cowboybart]

I don't have a proper steady rest or a spider for may lathe. Everything is done between centers or by hand. I got a spider made but not installed and trued. Without those options I can't chamber, I have to go use a friends lathe and coordinating has been difficult.
I'm not a machinist (just play one on TV!! ;_)), I am kept busy driving my truck, fixing it, fixing heavy equipment and running said equipment.