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lee bullet seating die mod

Posted: 20 Jun 2019 20:42
by chet
this mod totally eliminates bullet seating concentricity problems, take a 223 full sized brass case, insert a bullet in the case upside down seat it flush with the neck, put it in a drill press or a hand drill will work, tighten the chuck good, make sure there is no primer in the case, take the top of the lee die out of the die, you will notice it is hallow, file the base area of the 223 case about 5/8 up from bottom till it slips in the hallow area of the lee seater top, make it real shiny no burrs, i finished with 600 grit, cut it off around 5/8" long, deburr inside of case well and check to see that it slides easy in the lee die, take a spring about 1 1/2" long that fits in the case my spring is about 5/16" dia, had to file it a little to slip in the case, put the spring in the lee die and the case, assemble, you will now see that the bullet starts to center the moment it contacts the floating seater, before this mod the bullet has to travel around 3'8" to start centering, by then its too late, you will get shavings and the bullet runout will be at it's worst, this mod works slick, i have done all my lee seaters rifle and pistol, make a huge improvement.

chet

Re: lee bullet seating die mod

Posted: 21 Jun 2019 03:46
by GasGuzzler
I like the concept but some of the details I'm sketchy on.

Re: lee bullet seating die mod

Posted: 21 Jun 2019 04:26
by Ranch Dog
Pictures or videos of the work?

Re: lee bullet seating die mod

Posted: 21 Jun 2019 06:02
by RBHarter
If I'm visualizing correctly he's replacing the floating seating "ball" with a fitted slip collar and the spring forces it down enough to hold the bullet straight in the case and die .

Re: lee bullet seating die mod

Posted: 21 Jun 2019 08:23
by chet
i am not replacing anything, i will get a pic later, one thing i want to add, if you take a allen wrench or a pencil and insert it in the bottom of the die you will feel play up and down on the floating bullet seater, when the mod is done the minute you try to push up on the seater it is spring loaded

chet

Re: lee bullet seating die mod

Posted: 22 Jun 2019 10:37
by Macd
Looks interesting. Is the original seating plug still used?

Re: lee bullet seating die mod

Posted: 22 Jun 2019 11:47
by horseman
Alright, I'll admit it, I'm a dummy. The picture shows a piece of brass (assuming the "shortened" 223 case mentioned) with a spring in it going into the top of the bullet seating die (?). So, wheres the rest of the case with the bullet that we seated upside down and flush with the neck? Why? Also why did we place said item on our drill press (hand drill will work)? What are we drilling and for what purpose. I believe I'm missing something or something is missing from description, but like I said I'm a dummy.

Re: lee bullet seating die mod

Posted: 22 Jun 2019 15:31
by chet
Macd wrote:Looks interesting. Is the original seating plug still used?
yes it is, i made a few different ones on my lathe, one for flat nose bullets, it controls the overall length more precisely.

chet

Re: lee bullet seating die mod

Posted: 24 Jun 2019 09:19
by chet
horseman wrote:Alright, I'll admit it, I'm a dummy. The picture shows a piece of brass (assuming the "shortened" 223 case mentioned) with a spring in it going into the top of the bullet seating die (?). So, wheres the rest of the case with the bullet that we seated upside down and flush with the neck? Why? Also why did we place said item on our drill press (hand drill will work)? What are we drilling and for what purpose. I believe I'm missing something or something is missing from description, but like I said I'm a dummy.
hi horseman
not a problem, only reason for chucking the case in a hand drill or drill press is to file down the lower area of the 223 case to slip in the top area of the lee die, no drilling and after the lower case is fitted to slip in the top of the die, then cut the case about 5/8" up from the bottom, debur inside and outside and you done. ya got it


chet

Re: lee bullet seating die mod

Posted: 24 Jun 2019 09:42
by larryw
Yea, I'm a bit fuzzy also??
Why are we seating a bullet upside down when only the bottom of
the case is used??? Very interesting... +1