Full length sizing
#1
Thread Starter
Join Date: Feb 2003
Location: gully mn USA
Posts: 93
Full length sizing
I have read on a few post where people suggest putting a washer or something between the ram and the die when full length sizing brass. What is this for? I didn't see this written in my reloading book, is this a trick or standard practice?
Thanks.
Thanks.
#2
Guest
Posts: n/a
RE: Full length sizing
Maybe they are talking about squaring the dies setting up. check out this link. Tells alot about it. Very imporant for seating die setup. But using a plain ole washer isn't good. It has to be uniform by .0005" I think to be of any use. A home depot washer ain't that. I had my machinist here at work just mill me a nickel size piece of steel.
http://www.sierrabullets.com/xring/i...l1no1#loadtip1
And
http://www.sierrabullets.com/xring/i...ol1no2#loadtip
http://www.sierrabullets.com/xring/i...l1no1#loadtip1
And
http://www.sierrabullets.com/xring/i...ol1no2#loadtip
#4
Join Date: Sep 2004
Location: Southern California
Posts: 323
RE: Full length sizing
If you screw your die all the way down so that it contacts the shell holder before tightening the locking ring on the die, you will be squared up. You will also ensure that you are full length sizing your brass, as the stroke forces the shell all the way into the die until it is stopped by the shell holder. If you put a washer between the shell holder and the die, you won't be full length sizing the brass.
The "squareness" problems arise when you try to use a full length sizing die to neck size your bottle necked rifle cases. This can be done quite satisfactorily if you back the die away from the shell holder a bit so that it does not contact the shell holder on the stroke. However, you DEFINITELY need to square the die up first before locking it in place. This is where the washer or shim comes into play.
I personally use a Starret thickness guage to do this rather than a wsher, because I share the other guys' concerns about the flatness of an inexpensive washer. I use this guage because I happened to own one; however, these are rather expensive, and you can use a piece of shim stock and get the same results. I have gotten satisfactory results by leaving my shell holder at the top of the stroke, then screwing the die in with the guage betwen the shell holder and the die, until the die is tight against the guage or shim. The reason for doing this is that the outer threads on the die are coarse enough that you may not be exactly square with the shell holder; there is a fair amount of "play" in these threads. I then tighten the locking ring on the die, lower the shell holder and remove the thickness guage. This sizes the neck perfectly, does not contact the shoulder, and provided I use care in centering the expander ball each time, I get good concentricity, measuring about 0.001" runout.
The "squareness" problems arise when you try to use a full length sizing die to neck size your bottle necked rifle cases. This can be done quite satisfactorily if you back the die away from the shell holder a bit so that it does not contact the shell holder on the stroke. However, you DEFINITELY need to square the die up first before locking it in place. This is where the washer or shim comes into play.
I personally use a Starret thickness guage to do this rather than a wsher, because I share the other guys' concerns about the flatness of an inexpensive washer. I use this guage because I happened to own one; however, these are rather expensive, and you can use a piece of shim stock and get the same results. I have gotten satisfactory results by leaving my shell holder at the top of the stroke, then screwing the die in with the guage betwen the shell holder and the die, until the die is tight against the guage or shim. The reason for doing this is that the outer threads on the die are coarse enough that you may not be exactly square with the shell holder; there is a fair amount of "play" in these threads. I then tighten the locking ring on the die, lower the shell holder and remove the thickness guage. This sizes the neck perfectly, does not contact the shoulder, and provided I use care in centering the expander ball each time, I get good concentricity, measuring about 0.001" runout.
#5
Nontypical Buck
Join Date: Feb 2003
Location:
Posts: 3,516
RE: Full length sizing
jmfa1957:
According to my Redding Full Length sizing instructions after you screw the die down touching the shellholder with the ram at its highest point, one is then to back off the die half a turn and tighten. Since the die will not touch the shellholder one cannot square the die that is why you place a washer/spacer between the die and shellholder to take up the difference of the counter half turn. While keeping the ram raised and every thing in contact, you can now tighten the set screw on the lockring and your die is squared, and you will be full length sizing because you followed the Full Length instructions.
With RCBS dies using a washer/spacer is not necessary because one screws the die down a quarter turn after the shell holder is reached, so applying pressure with the ram and tightning the set screw will square the die. If you are using a RCBS Rockchucker press, one can cam it over making it easer to tighten the die's lock ring set screw.
With Forster Dies one screws down the die till it hits the shell holder firmly, so the die is squared after the lock ring is tightened.
I square all dies my dies (full length , neck sizer, seating, and case mouth expanding).
I don't own any other dies, so I haven't squared them.
Good luck.
According to my Redding Full Length sizing instructions after you screw the die down touching the shellholder with the ram at its highest point, one is then to back off the die half a turn and tighten. Since the die will not touch the shellholder one cannot square the die that is why you place a washer/spacer between the die and shellholder to take up the difference of the counter half turn. While keeping the ram raised and every thing in contact, you can now tighten the set screw on the lockring and your die is squared, and you will be full length sizing because you followed the Full Length instructions.
With RCBS dies using a washer/spacer is not necessary because one screws the die down a quarter turn after the shell holder is reached, so applying pressure with the ram and tightning the set screw will square the die. If you are using a RCBS Rockchucker press, one can cam it over making it easer to tighten the die's lock ring set screw.
With Forster Dies one screws down the die till it hits the shell holder firmly, so the die is squared after the lock ring is tightened.
I square all dies my dies (full length , neck sizer, seating, and case mouth expanding).
I don't own any other dies, so I haven't squared them.
Good luck.