I have a Cooper 6.5 x 284, I use Norma and Lapua brass. My question is after full length resizing the bolt is hard to close. When I take a case that has been shot the bolt closes with ease but after resizing it is very tight. My dies are Redding 6.5x284 win and my gun is stamped 6.5x284, Could I have the wrong die? The gun is very accurate and I have had this problem since day one, I'm just not sure how this will affect the gun down the road. I don't have any pressure signs.

Thanks
-Max

Hi!
Sounds like a headspace issue... either the rifle's chamber is too short, or your loading dies are not set to "bump" the case shoulder far enough back.
Other possibility is that the bullet is seated too far forward so it's hitting the riflings, but that shouldn't cause very much bolt "stickiness"... I'd bet headspace.

Is the die set all the way down to contact the shoulder, or shell holder? The case is apparently stretching/not being bumped.

Are you using enought lube?

My Cooper 243 AI is also a tight fit, but way accurate.

Sounds like the neck expander is lengthening the case when it is being pulled back through the neck. To confirm this, take the expander button out of the die and size a couple of cases and see if they still fit the chamber.

You might consider using a separate Lyman "M" expander die to do the neck expansion, or one of the neck bushing dies that only squeeze the neck enough to hold the bullet again, and don't need any neck expansion after they are used.

Two possibilites

CMcDermott has the first thing that I would check

The second thing is to check that your bullet seating die isn't screwed down to far. Sometimes people will screw them down like a sizing die and the die will hit the case mouth as the bullet seats. This will cause the neck to get shoved back and give you a bulge at the shoulder. This is often to small to see but big enough to cause the rounds not to chamber easily.

Thanks for the suggestions, I will try and just neck size with addition lube. The bolt was hard to close without a bullet in the sized case. Now I have a question on neck sizing... how far can I back the die off the shell holder to still be safe? I was thinking one full turn as a starting point.

-Max

Uuuhhh, before you start changing anything, I would get the problems you have on your plate now cleared up. Do you have a reloading manual? It should have a section on how to set up your dies. And a set of set-up instructions should have come with the dies. I think Redding also has a hot line you could call.

6.5X284 used to be a wildcat based on Winchesters 284 case. Then Norma legitimized it with factory made ammo. It is a possibility that your Cooper gun's chamber is mismatched with the Redding sizing die.

I switched to the Lapua brass that I had shot a while ago and all seems to be right. I full length resized and only neck sized (as per the Redding die instructions) and they both worked well. Is there that much difference in Norma brass vs. Lapua?

Thanks
-Max

Maxwell, ther can be a good bit of difference from one case mfg. to the other, but I'm betting die set up. You sound like you might be trying to neck size only, I think it's real simple, you are probably hittin the case body with the die, and actually moving the shoulder forward, or pulling it forward with the expander as someone else mentioned, but I'm betting your shoulder is just a pinch to far forward. It's really easy to tell, just screw your die in a full turn, size a case, and chamber that--bet you it chambers easily.

Good Luck--Don

quote:

Originally posted by maxwell:
I switched to the Lapua brass that I had shot a while ago and all seems to be right. I full length resized and only neck sized (as per the Redding die instructions) and they both worked well. Is there that much difference in Norma brass vs. Lapua?

Thanks
-Max

One of the good dies to have around if your switching brass for the 6.5x284 is this
http://www.sinclairintl.com/cgi-bin/category.cgi?catego...tem=RD74X&type=store

I've used some Hornady,Laupa and necked up 284 brass in my 6.5x284 just to compare.

quote:

Originally posted by Gaillo:
Hi!
Sounds like a headspace issue... either the rifle's chamber is too short, or your loading dies are not set to "bump" the case shoulder far enough back.
Other possibility is that the bullet is seated too far forward so it's hitting the riflings, but that shouldn't cause very much bolt "stickiness"... I'd bet headspace.

I agree that this is a likely cause. As you size your brass, the shoulder will move forward - the brass has nowhere else to go as it gets squeezed by the die. If your die is not set up to push this elongated shoulder back, you'll experience a case that gets more difficult to chamber after sizing.

Try getting a gauge like this:

http://www.sinclairintl.com/cgi-bin/category.cgi?catego...tem=HK-66&type=store

It will quantify any movements of the brass during sizing for you. Measure before and after you size. Eventually, you'll need the shoulder pushed back between .001-.002" to work the brass as gently as possible and avoid brass separation down the line. Cases sized such will chamber with just a hint of resistance.

A die set up for one type of brass will not necessarily achieve the same results for another brand of brass. There are minute differences between the different brands, and making as small an impact as .001" shoulder push back may take slightly different die settings for different brands. Either keep it to one brand of brass for one chamber (best solution), or adjust your die to compromise between the different brands. This is another reason why brass and dies go with one rifle only.

- mike