body die vs. fl sizing

[2433006300]

what is the benefit of using a body die and what does it do compared to a fl sizing die.

Thanks For your help

[hotbrass]

Whats a body die?

[stevec]

body die does not do the neck. only time you need a body die is if you have a necking die only.

Steve

[2433006300]

so mostly it main purpose is to improve the brass life.


thanks

[dolomite_supafly]

By using a body die you add a step to the process of reloading by seperating the neck sizing and FL sizing. On a positive note your brass will generally last longer. A FL sizing die contracts the neck then opens it back up while sizing the body. This leads to a lot of working of the brass. This working hardens and stretches the brass which makes trimming needed more often. I would get split necks after 3 reloads the old way but the new way has definitely exteneded that.

I switched to using a Lee collet sizer and a Redding body die. Since then my brass lasts longer and needs less trimming. Even though there is one added step the actual sizing is a lot easier.

Just my observations
Dolomite

[Tightgroups]

Dolomite, is correct. When you neck size over and over, sooner or later the case body will become to fat, and not want to chamber. At this point you have two choices, you could FL size the case, or just bump the case body in just enough to fit back snug in your chamber. And thats what the Redding body only die is for. And to my knowledge Redding is the only Mfg of this type of die.
Think about how much your moving brass around when you FL size it, the more, the shorter its life will be, and Lapua BR brass is not cheap, about $0.75 ea, and going up.
I dont know how many times some of my brass has been reloaded, but its some where around 12 to 14 times, or until the primer pockets start to get loose.
Mike.

[BrentWin]

I switched to using a Lee collet sizer and a Redding body die. Since then my brass lasts longer and needs less trimming. Even though there is one added step the actual sizing is a lot easier.


+1 And I only body size about every 3rd reloading.

[Moosetracker]

Same here, Lee Collet, Redding body die and Forster benchrest seater. I use the body die every 2-4 sizing depending on caliber. I set up the body die to bump the shoulder .002", using Larry Willis' Digital Headspace Gauge.

[Bark]

Same here, Lee Collet, Redding body die and Forster benchrest seater. I use the body die every 2-4 sizing depending on caliber. I set up the body die to bump the shoulder .002", using Larry Willis' Digital Headspace Gauge.
Yep Moose,going to use the EXACT same die set-up,just waiting for the Redding body die and Forster inline to come off backorder.Would appreciate it if you would describe how you set-up the body die to just bump the shoulder and not size the rest of the case. Thanks. Old Grumpy

[Tightgroups]

The Redding body only die, if used to bump shoulders, will also move the case body in, as much as if you had used a LF sizing Die.
I have a Redding body only die, but use it with a Forester neck bushing, shoulder bump die. This Forester die sizes the neck with a bushing, and will bump the shoulder back as much as you have it set for, but does nothing to the case body. That's where the Redding body only die comes in. Sooner or later the case body will get to wide for your chamber, (4 to 8 re loadings?) and this die will move it back in, but its only set to move the body in the minimum amount necessary to maintain a snug case to chamber fit.
I'm talking about reloading BR cases.
M.

[Moosetracker]

Same here, Lee Collet, Redding body die and Forster benchrest seater. I use the body die every 2-4 sizing depending on caliber. I set up the body die to bump the shoulder .002", using Larry Willis' Digital Headspace Gauge.
Yep Moose,going to use the EXACT same die set-up,just waiting for the Redding body die and Forster inline to come off backorder.Would appreciate it if you would describe how you set-up the body die to just bump the shoulder and not size the rest of the case. Thanks. Old Grumpy


As mentioned by TG, the body die only sizes the body a minimal amount. To set it up for a .002" bump on the shoulder I use the following procedure.

1. I take a case fire formed in my firearm. The case should be a tight fit so that it's as close as possible to chamber dimensions.
2. Set the case in the Digital Headspace Gauge and zero the gauge. Here's the link: http://www.larrywillis.com/
3. Insert a .003" shim on the redding body die and screw the die in the press till it's snug on the shellholder. Here's the link for the set of shims:
http://www.sinclairintl.com/product/6170/s
4. Resize the case with that set up.
5. Place the case in the Digital Headspace Gauge and get a measurement of the amount of shoulder bump.
6. If the bump measures .005" all you need to do is replace the .003" shim with a .006" shim and you get a .002" bump.

The beauty of this set up is that you don't need to touch the die even if you have multiple guns of the same caliber - you just change the shim in accordance with the bump you need. Also you can use another shim if you want more or less bump.

Occasionnally, you get a minimal dimension chamber where you can only get .001" or less with the body die. When this occurs, I use a dedicated shell holder which I sand on a flat surface to take off .001" or so.

Finally it's a good idea to keep a tight fitting fire formed case in your die box to test your setting with the Headspace Digital Gauge occasionnally.

Good luck.

[Moosetracker]

One more point. From my perspective, the fact that the Redding body die resizes the case slightly is a good thing. Not only is it needed occasionally, but by so doing, you're certain that the case is well lined up when you bump the shoulder, thus minimizing potential run-out in the upper part of the case.

My opinion.

[MikeCTX]

Thanks for the detailed write up, Moosetracker. Found it informative and simple and a great step by step method.