Rcbs FL question.

[nmbarta]

This might help you out a bit.
Your rcbs die has 14 threads per in.
Here's the math.
1÷14=.0714 per turn
.0714÷360 degrees = .00019 (.0002 for this)
.0002x10=.002
10 degrees = .002
360÷36=10 so 1/36th of a turn = .002

Most people move their die way too much when trying to set up for bumping the shoulder back.

Until you actually touch the shoulder, you won't get consistent results. The shoulder will move because of the pressure on the neck, sometimes even slightly grow right before you actually bump it back. The datum line can be pushed out slightly as the neck is being sized, and is then corrected when it makes contact with the die.

Good luck, hope this helps.

 

[WildRose]

I was kinda thinking the same thing. I pulled some out of the tumbler and re measured them. Not sure if there was still some lube on them or what but now that they are clean it's looking like it's only .001 some even as little as .0005. They still chamber fine. I'm probably going to load maybe 5 or 10 and see how the shoot.

Ahh, the lube can leave a deceptively short ring. I see it pretty frequently hence asking if you had miked them or just going off of visual observation.

 

[Grizzhunt]

This might help you out a bit.
Your rcbs die has 14 threads per in.
Here's the math.
1÷14=.0714 per turn
.0714÷360 degrees = .00019 (.0002 for this)
.0002x10=.002
10 degrees = .002
360÷36=10 so 1/36th of a turn = .002

Most people move their die way too much when trying to set up for bumping the shoulder back.

Until you actually touch the shoulder, you won't get consistent results. The shoulder will move because of the pressure on the neck, sometimes even slightly grow right before you actually bump it back. The datum line can be pushed out slightly as the neck is being sized, and is then corrected when it makes contact with the die.

Good luck, hope this helps.

I may have to lower it back down a little to get it to hit. I think I will still load what I have done and just see if anything changes. Thanks!!

 

[Grizzhunt]

Ahh, the lube can leave a deceptively short ring. I see it pretty frequently hence asking if you had miked them or just going off of visual observation.

I wiped them all down when I checked but I must not have gotten everything off. After running the tumbler with brand new media they look like new cases.

 

[azarcher10x]

It sounds to me like you might need to try a separate body die and neck sizing die along with a case gauge. The chamber on my 300 RUM is minimum spec, so I usually only neck size. I started having case extraction issues when neck sizing only. Decided to body size, and the shoulder grew .002- .003. Had to remove a bit of the bottom of the die to get shoulder where it needed to be. Now I body size, then neck size and trim.

 

[25WSM]

Grizhint I was the Smith trying to help you out last time. I am so happy you got the tools you need. On the 243 you said it was a little to deep on the shoulder so you backed out a full turn. A full turn is around 71 thou or .071 this is why you don't see it coming down the neck to the junction. I bet you only needed to come up about .005 tops and that's a guess because I didn't see any mention of how much to deep you were. If you were to put 2 dots on your lock ring about 1/8 of an inch apart you will move about .003 thou per dot. Once you are close like just touching the shell holder close you barely move the die at all to get correct bump. You 243 is basically neck sizing 3/4 neck right now. But it isn't at all resizing the body. If you call me I will go over anything you want to about it. It is a very important adjustment that the factories don't even tell you. Die companies want you to be able to get that piece of brass in a chamber and bolt closed and boom. They don't care about your accuracy or case life. Biggest reason for cracked necks. Dies squeeze your neck way to tight and then expand them back big to fit the bullet with the right grip. Why. Because different brass neck thickness means you can't have one diameter neck on a die and get the same tension. That's why we buy bushing dies. Crush the neck to the right size one time it's done. No over working the neck to make it hard and brittle. With proper anealling you will lose primer pocket tightness before you crack a neck. Personally msg sent I hope.
Shep

 

[Grizzhunt]

It sounds to me like you might need to try a separate body die and neck sizing die along with a case gauge. The chamber on my 300 RUM is minimum spec, so I usually only neck size. I started having case extraction issues when neck sizing only. Decided to body size, and the shoulder grew .002- .003. Had to remove a bit of the bottom of the die to get shoulder where it needed to be. Now I body size, then neck size and trim.

In the title I put FL for full length die, I've never used a neck die but I read a lot of people just set a full length to just bump the shoulder somewhere around .002 to .005 for a hunting rifle. I'm guessing all my guns have a Sammi spec chamber I've always just told the smiths the caliber I want it chambered in.

 

[fmuguira]

25 WSM is right on about a full turn of the die being like .070 .... something in your measurements is amiss if you went from .009-.010 to .003 of shoulder bump with a FULL turn of your die!!

Good Luck

 

[Grizzhunt]

Grizhint I was the Smith trying to help you out last time. I am so happy you got the tools you need. On the 243 you said it was a little to deep on the shoulder so you backed out a full turn. A full turn is around 71 thou or .071 this is why you don't see it coming down the neck to the junction. I bet you only needed to come up about .005 tops and that's a guess because I didn't see any mention of how much to deep you were. If you were to put 2 dots on your lock ring about 1/8 of an inch apart you will move about .003 thou per dot. Once you are close like just touching the shell holder close you barely move the die at all to get correct bump. You 243 is basically neck sizing 3/4 neck right now. But it isn't at all resizing the body. If you call me I will go over anything you want to about it. It is a very important adjustment that the factories don't even tell you. Die companies want you to be able to get that piece of brass in a chamber and bolt closed and boom. They don't care about your accuracy or case life. Biggest reason for cracked necks. Dies squeeze your neck way to tight and then expand them back big to fit the bullet with the right grip. Why. Because different brass neck thickness means you can't have one diameter neck on a die and get the same tension. That's why we buy bushing dies. Crush the neck to the right size one time it's done. No over working the neck to make it hard and brittle. With proper anealling you will lose primer pocket tightness before you crack a neck. Personally msg sent I hope.
Shep[/QUOTE. Thanks for the info, I did say it was moving them around .01 or .009 when set the factory way. So I back it out in small portions for the first few I tried and then I got ****ed off it wasn't changing anything and put a mark on the die body and spun it clear around. And you have the rest of the story. It doesn't seem to be consistent so I might have to change it again and get it to hit the whole shoulder.

 

[25WSM]

Nmbarta I missed your post perusing down the path here. But you put that so perfect in writing. I am jealous as heck people can write so perfect what their brain tells them. So I basically said what you said again but with some more info from the last thread that was started. I know griz is isn't getting shoulder bump on his die backed out 1 turn. It's still a full length die that is now sizing 3/4 the way down the neck. There is something griz is doing or not doing while measuring his headspace. I can't type a full page comprehensive how to set a proper headspace using a full length die. Well actually I can. I'll see if he calls and I walk him through it, then see if I need
too.
Shep

 

[30BR]

Maybe some of you read through the problem I was having with case head separation a few weeks ago. I bought a comparator gauge and I hope I fixed the problem. But I decided to check how far I was moving the shoulder on all my rifles. My 243 is moving a lot so I backed my die out a fill turn and got it down to .0035 but I noticed that the case neck isn't getting all the way to the bottom. Is that ok to load like that? I assume my 300 did the same thing but I haven't shot any of the loads yet. So I sized 25 I guess I will test it out and see.

Mike the OD of loaded rounds, and order a Forster F/L sizer to yield that OD minus .002". The bushing sizers have some taper, and will always leave some neck unsized. Foster does this for just a few bucks. Make sure you clean the die very well before using it.

 

[Frank Kalisz]

I use the multi-thickness set of Redding "Competition" shell holders so I don't have to move my dies back at all. I like to size my brass with the die making contact with the holder because I believe that gives me more consistent results. I simply choose whichever shell holder that gives me the bump that I want (typically 0.001"). They should work with any brand of FL die

ps - And if one of those shell holders doesn't give you the bump you want, I would say your die is definitely out of spec.

 

[Frank Kalisz]

Mike the OD of loaded rounds, and order a Forster F/L sizer to yield that OD minus .002". The bushing sizers have some taper, and will always leave some neck unsized. Foster does this for just a few bucks. Make sure you clean the die very well before using it.

I also use the custom-honed Forster "Benchrest" FL sizing die, and I use it with the Redding "Competition" shell holders that I discussed above. This Forster die is just a conventional FL sizer die that doesn't use bushings, and Forster factory will do a great job to hone the neck of that die to whatever you want. I had Forster hone mine out to 0.004" inches less than loaded neck diameter (that came out to 0.334" for my 308win). I use my Forster FL sizer without the expander spindle, and then I use a separate expander mandrel die (as sold by Sinclair or 21st Century) to get a very consistent 1.5thou tension as measured with my pin gauges. I like using the separate mandrel die because I get very low bullet runout without needing to turn necks. And of course the Redding shell holders also give me exact headspace clearance that I want.

ps- Down side of my custom honed FL die setup is that it assumes that you will always use brass with similar metal thickness in the neck, and of course you cannot change it once you get it honed. It works well for my 308win because metal thicknesses of my Lapua and my Lake City brasses are very similar. I did find that my die would not size Winchester-brand brass necks tight enough - but fortunately I think that stuff is junk anyway. I still keep my old Lee neck collet die around just in case I get something that doesn't fit, but I haven't had that problem yet with good quality brasses

 

[25WSM]

I talked to griz and found out a little more that helps solve the big picture. First is he has always adjusted dies by the directions. Touch shell holder to die and lock down. Has worked for him until now. This 300prc die must be crushing his brass way more than it should. Easy to fix if you know how to measure case headspace which he didn't have the tools to measure with. He has the tools and knows how to do it now and I believe he will have perfect resuts next set of brass. As far as the 243 brass he was measuring brass that was factory unfired and then measuring it again unfired but sized. That's why it seemed like it was doing headspace and only 3/4 of the neck at same time. I'm pretty sure he is going to nail his die setup next time. He has a very perfect stable of cartridges to work with to. They are all on my favorite list.
If it was only taught to set up dies off of headspace numbers you get from your brass from your rifle this could have been prevented. It's just not the common knowledge gained from manuals and instruction. It needs learned from places like here and from mentors at the range. I know I didn't learn it in a book.
Shep