308 neck sizing
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bigedp51
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This happens with many type dies and I'm not sure exactly why this happens.
But a taper crimp die will close up the case mouth and cure the problem.
Many reloaders use a Lyman type "M" expander die that aids in straight inline seating. And a taper crimp die will close up the case mouth. The RCBS AR Series .308 and .223 dies come with a taper crimp die.
Below are pistol cases showing how straight the bullet is when using a type "M" expander. And the case on the left shows a tilted bullet. And if the seater plug is not a perfect fit on the bullet you will induce bullet runout.
Below just bumping the case mouth onto the step allows the bullet to start straight into the case. And if this causes feeding problems the taper crimp die will streamline the case mouth.
Bottom line, I intentionally flare my case mouths on some of my cases and close them with a taper crimp.
Remove your Lee dies expander and size a case and see if the case mouth is flared. If not you can just use a expander die to bring the necks back up to the proper diameter.
But a taper crimp die will close up the case mouth and cure the problem.
Many reloaders use a Lyman type "M" expander die that aids in straight inline seating. And a taper crimp die will close up the case mouth. The RCBS AR Series .308 and .223 dies come with a taper crimp die.
Below are pistol cases showing how straight the bullet is when using a type "M" expander. And the case on the left shows a tilted bullet. And if the seater plug is not a perfect fit on the bullet you will induce bullet runout.
Below just bumping the case mouth onto the step allows the bullet to start straight into the case. And if this causes feeding problems the taper crimp die will streamline the case mouth.
Bottom line, I intentionally flare my case mouths on some of my cases and close them with a taper crimp.
Remove your Lee dies expander and size a case and see if the case mouth is flared. If not you can just use a expander die to bring the necks back up to the proper diameter.
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6.5-300 BEE
Well-Known Member
Insofar as I know Lee only makes 2 kinds of sizing dies: FL and collet. In the 20 odd sets I have I've never seen a rifle case neck expanded. (except when using a neck expander die as for cast bullets)
bigedp51
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You are correct about the Lee dies and my mistake and brain lapse. But if you read enough posting you will see case mouths problems that are flared or smaller in diameter.
If the OP does have a Lee collet die then my guess is the case mouth is not being squeezed by the collet properly.
6.5-300 BEE
Well-Known Member
Turns out that is intentional. I found this on Lee website. If it causes you any problem chambering, you can use the Lee crimp die for 308 to fix it. The are clever !
"If you're a long-time user of Lee Collet Neck Sizing Die you may notice we have modified the Collet so a small portion of the neck protrudes through the end of the Collet-Sizing portion. This often-requested modification was implemented in 2019.
This change allows the portion of the neck that protrudes above the Collet to remain in its fire formed condition. This provides a natural flare to the case neck allowing easy and concentric seating of bullets. This is especially important when seating cast bullets or low drag coated bullets.
Noted author and cartridge designer M. L. McPherson has suggested this modification for years for its ease of use, better function and improved accuracy."
"If you're a long-time user of Lee Collet Neck Sizing Die you may notice we have modified the Collet so a small portion of the neck protrudes through the end of the Collet-Sizing portion. This often-requested modification was implemented in 2019.
This change allows the portion of the neck that protrudes above the Collet to remain in its fire formed condition. This provides a natural flare to the case neck allowing easy and concentric seating of bullets. This is especially important when seating cast bullets or low drag coated bullets.
Noted author and cartridge designer M. L. McPherson has suggested this modification for years for its ease of use, better function and improved accuracy."
6.5-300 BEE
Well-Known Member
Yeah me too. Have to see if I can get a collet die in 30-30 as I mostly shoot cast and that would avoid the extra step of neck expansion.
My Marlin 30-30 1947 rifle marked "SECOND".
My Marlin 30-30 1947 rifle marked "SECOND".
redneckdan
Well-Known Member
Yeah I noticed this change too. Long time lee collet die user. Most recent die set is 6creed and I noticed the collets leave a larger bump between the fingers (rotate 1/8 turn and size again) and the case mouth has a flare. Didnt like it at first but hasn't been a problem with chambering.
