neck tension help

mikeman20

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Im having trouble i just noticed with too much neck tension, im using 180 gamekings and the copper is getting shaved off when i seat them! this is after deburring the neck and everything.
Heres an example:

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is there a way to set the neck tension on very old (atleast 20 years) lyman "ideal" dies? if not then am i going to have to buy new dies?
 
You say you're deburring them- are you chamfering the inside of the neck as well? The boattail helps to make seating easier, but if you're leaving the inside edge sharp, that could account for some of that.
I'm not familiar with Lyman "Ideal" dies, but I'm wondering also whether the expander button is worn or the wrong size? Have you had any problems before? Are the 180 Gamekings a new bullet for you?
 
Doesn't look like a tension issue. You say "deburring" - that's knocking off the burrs from the outside of the neck. You need to "chamfer" the inside of the neck. You might also try using a piece of steel wool on a turning case to polish after chamfering, if the bullets are still getting scraped up.
 
You say you're deburring them- are you chamfering the inside of the neck as well? The boattail helps to make seating easier, but if you're leaving the inside edge sharp, that could account for some of that.
I'm not familiar with Lyman "Ideal" dies, but I'm wondering also whether the expander button is worn or the wrong size? Have you had any problems before? Are the 180 Gamekings a new bullet for you?

sorry for the bad terminology but what i did was chamfer them, not debur them. I am brand new to loading, so i have no experience to fall back on. heres a picture of the expander button thing and it says .308 on it.

img22991.jpg



it does look well used, but is there anything else to this equation that would cause the problem?


edit: will get pics up of prepped brass, you guys posted before the pic uploaded
 
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I don't see a problem with what you're experiencing. How does the ammo shoot? That is what I'd be worried about...

havent gotten to shoot any of these yet, so i couldnt say. i figured a big gash out of the sides would effect accuracy in ways that i dont want
 
its not actually as bad as the picture makes it look because of the lighting, but its definitely not a razor, ill try something sharper and see if that works
 
checked the bullets, almost exactly .308, then realized i should check the sized cases (duh!) and they were all about .304. this is too much tension? or would it be the chamfering.
 
Try a VLD chamfer tool. Puts longer chamfer on the case and helps reduce the peeling you are experiencing.

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If this is for a Match Rifle then you can lighten up the neck tension to about .001-.002
 
It looks as though a chamfer tool with a lower angle on it may solve your problem, as suggested above.

Different brass may behave differently or annealling this brass should help too.

A little bit of shaving won't hurt much but it definitely isn't desireable.

Worst case you might need a slightly larger expander button but I would try a different chamfer tool and/or brass first.
 
If you are new you don't have a drawer full of bits and pieces.

I have loaded several hundred thousand rounds of match ammo in brand new cases. I cannot champfer each case, and I know a virgin case mouth would scratch the bullet.

I set my Dillon up with a 303 Brit sizer die in the first position. the die is backed out a long way and the neck sizing button just comes down enough to kiss the case mouth and bell it out (much the same was we do with pistol cases). The bullet seats without ever touching the case mouth and the seating die uses a taper crimp to smooth out the belled mouth.

You can buy a M die to do this, our use the expander die on a 32ACP die set, if you happen to have that laying around. I think a 8mmMauser decapper die would do it too.

Lee Valley sells 11 degree reamers that chuck in your drill. I put the drill in a vice, and then champfer all the case mouths for my own brass prep.
 
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