6.5-284 to 6mm-284 sizing problem HELP!!

[nmkid]

So, today I got my RCBS sizing dies from a fellow member. The set included a 25-284 die. So, I ran 10 Lapua 6.5 brass through it first and then through the 6mm-284 die with the stem removed. Went slicker than snot. However, I then noticed that all the reformed brass had a, "bell" or maybe more correctly it had flared out at the mouth of the case. Now what?

 

[SHootSTraight22]

I don't know if it would help any but if I ever step cases down I would make sure I anneal the snot out of it plus size in multi steps..

 

[SHootSTraight22]

So, today I got my RCBS sizing dies from a fellow member. The set included a 25-284 die. So, I ran 10 Lapua 6.5 brass through it first and then through the 6mm-284 die with the stem removed. Went slicker than snot. However, I then noticed that all the reformed brass had a, "bell" or maybe more correctly it had flared out at the mouth of the case. Now what?

Are you saying the cases flared back out at the mouth from memory??

 

[ed k]

When i had mine i simply ran them thru the 6-284 die and shot away. These were lapua brass. Have you tried this? ED K

 

[nmkid]

So, today I got my RCBS sizing dies from a fellow member. The set included a 25-284 die. So, I ran 10 Lapua 6.5 brass through it first and then through the 6mm-284 die with the stem removed. Went slicker than snot. However, I then noticed that all the reformed brass had a, "bell" or maybe more correctly it had flared out at the mouth of the case. Now what?

Are you saying the cases flared back out at the mouth from memory??

Well, I guess. The rest of the neck is properly sized except for the flare right at the mouth of the case.

 

[nmkid]

When i had mine i simply ran them thru the 6-284 die and shot away. These were lapua brass. Have you tried this? ED K

No. I don't even have the rifle yet. The action was just sent out a week ago.

 

[LRPV]

Is second die you used a standard 6/284 full length die or is it a bushing die? If it is a standard full length die, you have sized the necks down way more than you needed to since you took the expander out. You'll be lucky to get a bullet seated in it. Put your expander back in it. If it was a bushing die, it may or may not let you get the brass chambered. If the bell isn't too excessive, it won't be a problem as long as they chamber and will be gone after the first time you shoot them.

 

[nmkid]

Is second die you used a standard 6/284 full length die or is it a bushing die? If it is a standard full length die, you have sized the necks down way more than you needed to since you took the expander out. You'll be lucky to get a bullet seated in it. Put your expander back in it. If it was a bushing die, it may or may not let you get the brass chambered. If the bell isn't too excessive, it won't be a problem as long as they chamber and will be gone after the first time you shoot them.

You got it!! I put the stem back in and sized them again. I had to lube like crazy, it was tough going but, it worked! OK. First episode over with the new gun and it's still getting re-barreled!! LOL.

 

[nmkid]

Well, this is getting to be a real b****. Got the flare problem taken care of so I decided I would just slightly clean up one of the cases as most were reading about .017 after resizing. Ran a case through the expander mandrel. Then...The neck was so tight no way would it go on the turning mandrel. Ran it in the expander again, no go on the turning mandrel. NOW WHAT???

 

[CJ6]

I wouldn't use the carbide expander button on the F/L die to due too much "EXPANDING" with the newly reduced neck diameter (brass is too thick/neck inside diameter too small)for that size of button. A solid mandrel expanding die from K&M/Sinclaire will do a much better job, and not damage the stem in the F/L die which will happen soon trying to push/pull it through with thick/undersized (ID) necks.

 

[noload]

If you know anyone with a lathe, they could make any size mandrel you need to expand the case neck. Or any size mandrel for your neck turning tool.
I also would be using a Sinclair sizing mandrel to do this.

 

[nmkid]

Well, good or bad here is what I finally ended up doing. I annealed all the cases and then ran all of them through the Sinclair expander again. I would say at least 80% "loosened" up. I seated a bullet in one of the cases that still felt pretty tight. To my surprise it seated much, much easier than I would have thought. So, at this point I'm done until I get the gun put together and fire all the cases one time. The case should expand more than enough and at the point I will use my bushing die. Hoping anyway. Thanks for all the help guys.