Matter of opinions

JWFilips

Well-Known Member
Hi Folks,
I have about 400 pieces of .243 Brass that has been 8x shot in my 1980's Ruger 77V ( Thumb Safety) with only cast bullets ( no loads exceeding 2000 fps)
On first firing, cases were annealed and FL resized in RCBS dies. After that they were only neck sized. Now they are getting hard to chamber because the case body has expanded enough that it become difficult to chamber in this rifle because of a slightly out of center chamber.

Back in the 80's shooting jacketed at 3500 fps + I could never neck size because of this! So I adopted the practice of partial FL sizing ( sizing with the RCBS FL die until 2/3 rds of the neck was sized and that brought the body back to chamber-able tolerance! ) My concept was that the unsized 1/3 rd of the case would help center the cartridge in the chamber and the case body would fit in the out of round body of the chamber.

So my plan is to do the same with this Cast bullet shot brass....anneal the necks and partially FL resize!
My buddy however seems to disagree and said I either have to completely FL size this brass or get a Body sizing die!
Matter of opinions!....Looking for some more opinions on this!
:headscratch:
 

Brad

Benevolent Overlord and site owner
Staff member
If you partial FL size and it chambers fine then all is good.
I bet the shoulder has pushed forward a little. This is where the Stoney Point headspace gauge is so nice. You can measure head to datum line on shoulder of a once fired case. Then you can measure cases when they get difficult to chamber. Aneal and push should back .001 to .002 below the recorded measurement.
 

Brad

Benevolent Overlord and site owner
Staff member
Oh, and opinions?
You won't find many of them here and certainly not closely held opinions. :rofl:
 

Rick

Moderator
Staff member
My opinion is that Brad is right. If you don't have such a headspace gauge you could smoke the NK and shoulder of a round with the bullet seated and see where it's tight and if it's hitting the shoulder before the bolt is fully closed. You could also F/L size all the brass once and then most likely go back to your NK sizing as you have been doing. Was always my practice with NK sized bottle neck brass to F/L size slightly bumping the shoulder every once in awhile just as an insurance policy of the shoulder not moving.
 

Ian

Notorious member
I'm also of the opinion that Brad is exactly right, paricularly since he does headspacing the way I do:p

Bump .001" every single time you load them amd uour groups willbe a little more consistent from batch to batch. Honing out a resizing die in both the neck and body area so it minimally resizes brass to fit that ONE rifle's chamber and give neck tension desired for the size of cast bullets you shoot in it is the best scenario....and make sure you only bump back the shoulder a thousandth or so each firing, which will take a slightly different die setting foe each lot of cases.
 

Intheshop

Banned
The Stony point gage above is sort of S.O.P. for checking base to datum "line" measure. It's availibity has brought it into focus,IMO.

There are other ways of checking this measure.First find the prints for your case,there it should spell out or define where the industry bases their measures.BUT,it can be argued/discussed that you don't "have" to use that specified "datum line"...... meaning,you really only need a repeatable way to measure case growth for that particular chamber.

I think the datum line is checked at .400" on the .243 shoulder ( check the prints)..... but that could be .375 or .450. No,you won't be at the industry std. But it's more important that it's understood this is a comparison measure vs and industry "absolute". So,any convenient and hopefully, HIGHLY repeatable way to measure case length will suffice.

One test,is check the same load (tune) with old/er cases vs fresh cases,for accuracy. Old vs new can also check or confirm other areas of your handloading.Good luck with your project.
 
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Brad

Benevolent Overlord and site owner
Staff member
Even 1/16 of a turn moves the die down .004” so very small adjustments are required.
As the brass gets harder from firing/sizing cycles it will rebound more after sizing. This means the should might be pushed back initially but bounce right back after sizing. After maybe 4-6 cycles you might need to move the die down a little to get the same set back. Annealing would reduce the need for this.
Best thing about a gauge like I use is that I can repeat the movement every time. Tells me a bunch about my brass and how it is changed with firing/sizing cycles too.
 

JWFilips

Well-Known Member
OK,
I can tell you my problem is only about 1/4" above the head in 1 quadrant of the case (It is quite obvious...since that is where the witness marks show!) No reading problem in the shoulder area. If I index each case I would have no problem but I don't want to go that route.
& yes my sizing die is honed out to shoot cast bullets ( that to a lot of time on RCBS dies)
 

waco

Springfield, Oregon
Hey Jim. I have a sweet Vortex Bench Source annealing machine and would gladly anneal that brass for you at no cost.
 
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Ian

Notorious member
Someone mentioned dwell time at the top of the stroke....something I think is often overlooked. Also, when setting up the die, realize that you get one shot on each case to bump and measure the shoulder, if you need to make an adjustment, do so and check it with a "fresh" case.
 

Intheshop

Banned
For you guys with idle lathes N mills,look up a Redding instant indicator(bump gage).Then pare it down to the fewest parts/ops in a,I can name that tune in __ moves,foryee.Another of the 3 or 4 ways to check shoulder bump.
 

JWFilips

Well-Known Member
waco,
Thank you for you generous offer, however, i am trying for a range trip this Friday so I think I will just plod trough the annealing as I usually do to make sure I have brass ready by then.

BTW where does one get a Stony Point gauge? All the places I have looked say product is no longer available?
 

M3845708Bama

Active Member
Another good gauge is the RCBS presition mic. I use mine to match dies to rifle head space. Also found that a lot of presses have spring in frame which can mess up settings. For serious work use old rcbs o frame press to fl size.
 

JWFilips

Well-Known Member
Sorry for the dumb question: but how does one push the shoulder back .001"? What are the steps?
Do you smoke the case neck and shoulder and adjust the FL die down until it just touches the case neck on the top of the up stroke?
 

Rick

Moderator
Staff member
Sorry for the dumb question: but how does one push the shoulder back .001"? What are the steps?
Do you smoke the case neck and shoulder and adjust the FL die down until it just touches the case neck on the top of the up stroke?

What I have always done rather than try to measure .001", I smoke the shoulder, adjust down the die until it barely touches the shoulder & size, try in firearm. If still snug turn the die down again just very slightly, try in gun.
 

JWFilips

Well-Known Member
Oh, Thanks
I guess I actually have have been doing that because I am familiar with that proceedure. I didn't know what it was called ( I just call it partial FL sizing) Most times I only come down so that 2/3 to 3/4 of the neck gets sized and just leave a little fatness in the neck shoulder junction to align the case in the chamber........ I just thought there may be more to it than that