Case Neck Run-Out

AtownBcat

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Ok guys I will try to give you all the details you may need without killing you with the ones you dont.
My Dad had a Rem 700sps in 300WM. We got tired of trying to get it to shoot so we bought him a sendero. We had 100 pieces of WIN brass (shot twice) I had just learned of the value of checking for neck run out then bullet run out. Since we changed guns i had to FL size the brass. Had FL all the pieces when they were brand new then had just used the lee collet neck die after that.(the FL die is also a lee) The problem is when i FL sized the brass the neck came out in way worse shape than it went in. It was +/- .002 when it went in and came out .005-.007 out of round. I made sure the die was set up according to the directions even tried running them back through the neck sizer and some were corrected a little but never where they needed to be. It may just be the quality of the lee die. I trimmed this brass so that is not the problem. What do you guys think?
 
My guess would be the expander ball is causing you some problems. Try resizing without it and see if that helps. However, this might change your neck tension, so take some measurements as you go.
I don't check runout on any of my ammo, and I never use an expander ball on my dies.
 
"... when i FL sized the brass the neck came out in way worse shape than it went in. It was +/- .002 when it went in and came out .005-.007 out of round."

Not real sure I understand what you mean about being "out of round". But, with that die, it sure ain't because of the Lee Collet's expander. Nor is it likely to have anything else specific to the die, IMHO. Sounds more like a problem with the cases themselves.

No seater can make straight ammo if the case necks are bent. No sizer can make staight necks if they were originally formed improperly, at least not without some preperation work. Sounds to me as if you need a bit of light neck turning to even things up so the die has a chance!

I believe the Lee Collet neck die is the best available, at any price, for factory chambers.
 
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"... when i FL sized the brass the neck came out in way worse shape than it went in. It was +/- .002 when it went in and came out .005-.007 out of round."

Not real sure I understand what you mean about being "out of round". But, with that die, it sure ain't because of the Lee Collet's expander. Nor is it likely to have anything else specific to the die, IMHO. Sounds more like a problem with the cases themselves.

No seater can make straight ammo if the case necks are bent. No sizer can make staight necks if they were originally formed improperly, at least not without some preperation work. Sounds to me as if you need a bit of light neck turning to even things up so the die has a chance!

I believe the Lee Collet neck die is the best available, at any price, for factory chambers.
You must have misread my post. I did not say it was the collet neck die that i was having trouble with, I said it was the standard lee FL die. I have a RBCS case measuring tool. I measured the consintricity(sp) of the necks before i FL sized them +/- .002 and then again after +/-.007.

Trueblue you be on to something. And I realize you dont measure case or bullet runout. But if i remember correctly you are a fan of checking neck wall thinkness for consistent neck tension by correcting any problems in wall thickness aren't you also addressing any problems with neck run out?
 
It was +/- .002 when it went in and came out .005-.007 out of round.
Presume you're speaking of run-out. If eliminating the expander hasn't located the problem, try another die. If the expander is the problem, use your run-out gauge and straighten the stem. Since you're getting good results with your collet die, I doubt that the press is causing the problem. Some type of lube inside of the case neck will reduce somewhat the expander's influence, but it won't correct your problem.
 
My advice would be to buy a new lot of brass. My favorite in this caliber is Norma.
I'm a little confused by this suggestion. If my brass was in good shape before i FL resized it and it came out messed up, why would new brass be any different?
 
"You must have misread my post. I did not say it was the collet neck die that i was having trouble with,"

Not really. I was trying to suggest that using the Lee Collet neck die would avoid potential expander problems. Poorly worded, I had 3 visting small grandkids playing around me!
 
"You must have misread my post. I did not say it was the collet neck die that i was having trouble with,"

Not really. I was trying to suggest that using the Lee Collet neck die would avoid potential expander problems. Poorly worded, I had 3 visting small grandkids playing around me!
I follow you. The brass had been shot in my dad's other gun. It was to large to close the bolt on is new gun so they had to be FL sized. I prefer the collet sizer i would have rather done it that way.
 
I'm a little confused by this suggestion. If my brass was in good shape before i FL resized it and it came out messed up, why would new brass be any different?

A couple reasons for this.

#1: You already got rid of one rifle over this. May have been a bad one but my experience is that most 700's shoot pretty well. Yes, there are the exceptions but for the most part they are decent. I would have tried a different lot of brass before giving up on a gun.

#2: All brass stretches upon firing. Fire forming new brass is the most important stretch that it will have in its life. To some extent, it even forms a memory. Not to say that the dimensions of it can't be changed by FL sizing it.

#3: If you did have a bad chamber in your last 700, who knows how much tweeking this did to that brass.

#4: A chamber on the larger side allows the brass to stretch upon fire forming. I've had 300 WM's that would stretch .014 while fire forming. That's a lot of pressure on brass trying to get it back to minimum tolerances. Have you measured your shoulders??

I know a lot of people who use the Lee dies with great success. I doubt if it's the dies fault, unless it isn't set up properly. I am just saying that I would try something new. Mix it up a little. Good luck!
 
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