6.5x284 stuck cases

[Salar600]

Hi

At the first try of my new rifle I had some Lapua brass hard to extract.

Reload are within Hodgdon data.

I resize them all full length and try again the empty case to see if the problem was fixted but no. Half of the brass are ok and the other half are still hard to extract.

I trim them all and they all look the same with my caliper.

Any idea what could cause this problem?

Thanks for you help.

 

[Mikecr]

You likely have a visible web-line near the extraction grooves, where you can see expansion going on. How much is this expansion measuring from new to fired?
Was this new brass to begin?
What is the action?
How about a little history on the barrel finishing, including the chamber reamer used?

 

[Salar600]

All 100 brass have been shot in this Cooper only. Brass were hard to extract right after first firing.

Barrel is SS. As a production rifle, no information about reamer. Cooper said they use thigt reamer though.

Will have to look closser for a measurment but all brass look the same and measure the same whithin .00005'' I can't say for sure if it's realy the brass or from my skill.

 

[gohring3006]

I ran into this with a Savage.
Remington brass was hard to extract. I put some steel wool on a 20 ga. bore brush with some Remington 40x bore cleaner chucked it in a drill and polished the chamber, (not to mirror finish that is bad..). It helped a lot. Later I learned I should have tried a different brand of brass...

 

[AZShooter]

Can you be more specific on the extraction issue? Is the bolt hard to lift or does the resistance only occur when you try to move the bolt rearward?

Use a sharpie to cover the suspect cartridge's body. Cycle the brass through the chamber. You should be able to determine where the brass is hanging up. It could be the chamber needs polishing or it could be you need a small base die. There may be some strange anomaly to the chamber's shape.

Who made the FL die?

 

[Salar600]

the bolt is not hard to lift. The resistance occur when I try to move the bolt rearward.

Well, polishing the chamber is the next step I was thinking about.

Dies set is a Redding match set. Do you know who make a small base 6.5x284 die?

Thanks guys it all make sens.

 

[Mikecr]

I hope your load is safe

 

[Salar600]

Yap, I am at 50gr of H4831 with sierra 142 and Hodgdon give 50.3gr as max load.

 

[gohring3006]

I assume you did a proper load work up right?
I would make sure you are not over pressure before going forward on your quest.

 

[Salar600]

Good to ask, we never know.

I did a ladder test up to 51gr without any pressure sign. Found and confirm an accuracy node at 50.

 

[gohring3006]

Right! You never know, I personally know someone who thinks book max loads are safe in every rifle.
I would say you are having the same problem I was.
I polished the chamber and it fixed it...

 

[AZShooter]

And the part of the case that is sticking in the chamber is ?

If you need a small base die Redding makes one:

http://www.brownells.com/reloading/...e-6-5-284-norma-sku749005377-35349-68869.aspx

 

[Mikecr]

the bolt is not hard to lift. The resistance occur when I try to move the bolt rearward.

You shouldn't have to pull brass from a chamber, the bolt turn is suppose to do that. Makes me wonder about the bolt timing.
Single firing of new brass should not lead to popping extraction to begin, but even then it should be popping free before bolt turn is completed(even if beating open turn with a shoe).

I would consider communicating with Cooper. They might be interested in this.

 

[Salar600]

I put marker on a brass and there is marks all around the bottum. Will try polishing and small base die.

Thanks,