proper adjusting fl sizer die for headspace?

S

skidooracer_99

New member
okay guys i am a new reloader. i thought i had my stuff figured out but now i have a headspace question thrown into the equation. gun is a remington 700 vls in .243. ive finally had warm weather to try out some of my first batch of work up loads i made. i sized all my once fired factory loaded brass with the rcbs instructions of threading in die till it touches shell holder and then 1/8 turn more to cam over. all seemed well and simple. after firing [beeep], i noticed primers backing out, some of them were starting to flatten, and my cases were looking buldged in the web area from stretching which is my guess. these loads were minimum to about 2/3 of max and i didnt want to go any further.
the more i read up im believing those instructions of setting up my sizer die is pushing the shoulder back too far creating too much headspace for my chamber. its overworking the brass and could be a safety issue which is why im greatly concerned!! im curious if this is common and normal to have the die backed off the shell holder and by how much? and what is the best way to check and get the fl die set up properly for each guns chamber. what do you all do?? any suggestions at all would be greatly appreciated. thanks!
 
I think it might be wise to take your rifle to a competent gun smith and have him check your chamber specs...before going farther...

If your cases are expanding too much at the web and pushing out primers with moderate charges, your chamber may have been cut too short at the factory...and causing a headspace problem that is unrelated to your loads...

How do your cases from factory loads compare to your reloads??

I'm sure there will be more experienced reloaders chime in on this one..
 
You will need a tool to measure your fired cases to "know" how much the shoulder has expanded forward and to know how to set your dies for proper headspace. I have and like both of these tools for measuring cases and setting my sizing dies.
The RCBS Precision Mic is a great tool but is for one caliber while the Hornady Headspace gauge set will work with most rifle calibers. Here is a couple good articles using both tools:

http://www.inlandshooters.net/index.php?contentid=99
http://www.realguns.com/archives/035.htm
 
Last edited:
I think OldTurtles right.
and
If you have headspace issues, you'd probably be complaining about black soot marks all the way down the sides of the case. It's ok to have black round the neck but not down the sides.

Give us the rest of the data. What load did you use in this 243?
Case----
Primer--
Powder--
Bullet--
 
thanks RG! after reading those 2 links it makes quite a bit more sense to me. i need to be setting the sizer die to only push the shoulder back .002". so one of those gauges is the only way to tell? i have been noticing heavy sizing marks on the shoulders of my sized cases, i may have been right suspecting i was resizing way too much and giving me too much headspace. i didnt notice these stretching or primer signs on once fired factory rounds. only after i have resized them and fired for the second time. and oddly enough that buldge only appears on the winchester cases and not remington ones.
 
It's common on a lot of rifles to have swelling on the case wall just in front of the solid head of the case. The brass expands to fit the chamber and the solid and thickest area of the head of the case does not expand. There's a difference in swelling and stretching in this area of the case. Too much headspace will cause stretching and possible case separations. Bolt action Remingtons I'm familiar with usually have between .002 to .004" headspace. If you are pushing the shoulder back to zero or, depending on your die and shellholder, maybe a thousandth or two more, then you can have a little too much sizing of the shoulder. The firing pin pushes the case shoulder up to the front of the chamber, pressure causes the case to grip the chamber, pressure will push the primer back out of the case and hard against the bolt face. It can cause the primer to flatten a little or a lot. Pressure can also cause the front of the case to grip the chamber and the rear of the case will stretch back to the bolt face. By setting your sizing die to minimally push the shoulder back will extend the life of your brass and prevent possible case separations. Use the bent sharpened wire feeler method to feel inside the case wall for a depression or ring around the inside of the case. You can sometimes see this ring by shining a light inside the case. Sometimes Win brass shows this bulging more than RP or vice versa. Depends on the brass.
 
ski...kinda unrelated to your topic...if your not using it, try a tin of imperial sizing die wax - marketed by Redding-....makes re-sizing easier putting less on brass,press and you....a tin will last darn near forever.
 
okay so what im calling the bulging is more likely the case swelling as RG described. so this is fairly normal then? im gonna pick up an rcbs precision mic this weekend to check everything out. is the rcbs mic the better tool for measuring headspace than those gauges that mount to calipers? now if only i could get those damm set screws to stay put on my rcbs die lockrings once i finally get a proper setting. i never had to worry about that stupid setscrew because i was just setting my die to touch the shell holder and in 1/8 turn more, every time.
 
Last edited:
would the hornady set work with .243 and .204? that would save me buying two mics. basically i wanna know whats easier to use, more accurate and less finikey to measure with? cost doesnt really matter [beeep].
 
I have owned a lot of FL dies in my life and I have never had the problem your talking about. My first stop would be a gunsmith and have the headspace checked. If it does have a headspace problem it can be remeditied with parcial resizing.
 
well i didnt get to the city this weekend to pick up a rcbs case mic for .204 and .243 but i will next weekend. i think i might also pick up neck sizer dies too. i have a question with unfired new brass? once i get my fl sizer die set up to bump the shoulder back only .002 from a fired case, should i run my new brass through that "set up" fl die? just neck size the new brass? or fully fl size the brass with the fl die all the way down to the shellholder??
 
I had a probblem with pressure like you...only mine was flattened primers and under direction from the fine people of this forum i corrected the shoulder and pressure probs went away.Your pressure problems are severe to me take it to a smith to be sure why gamble with your life or body parts.good luck.
 
Last edited:
FIrst use starting loads in a reliable manual always. then try this method.

Take a your fired case. Remove the expander ball from the die. Start out with with the die about a nickels space above the shellholder. Resize the case, stick it in the rifle and see if it will chamber. Your are looking for a little bit of feel when the bolt closes. If it won't close at first or is too tight, lower the die in the press in small amounts until you feel the pressure change from hard to just a feel.
Then replace the expander ball, resize some cases and try again.
you have a minimum SAAMI sized chamber and were pushing the shoulder back too far.
I have used my method for years and no problems.
Hope this helps
Greg Harrison
 
Originally Posted By: skidooracer_99 okay guys i am a new reloader. i thought i had my stuff figured out but now i have a headspace question thrown into the equation. gun is a remington 700 vls in .243. ive finally had warm weather to try out some of my first batch of work up loads i made. i sized all my once fired factory loaded brass with the rcbs instructions of threading in die till it touches shell holder and then 1/8 turn more to cam over. all seemed well and simple. after firing [beeep], i noticed primers backing out, some of them were starting to flatten, and my cases were looking buldged in the web area from stretching which is my guess. these loads were minimum to about 2/3 of max and i didnt want to go any further.
the more i read up im believing those instructions of setting up my sizer die is pushing the shoulder back too far creating too much headspace for my chamber. its overworking the brass and could be a safety issue which is why im greatly concerned!! im curious if this is common and normal to have the die backed off the shell holder and by how much? and what is the best way to check and get the fl die set up properly for each guns chamber. what do you all do?? any suggestions at all would be greatly appreciated. thanks!

I seriously doubt that setting up the die the way the manufacture recommends is the problem. The reason is the die returns the case to SAMMI specs. In other words it's just like a new case, if it's not, RCBS will replace the die for you. In 40+ yrs of reloading for most everything from 22 Hornet to 338 Win Mag, I have never seen a die cause headspace, never! What happen's is that the die shows headspace problems in the chamber afer two or three loadings by the presents of a bright ring around the head of the case. That can be corrected by setting the die other than recommended or by going to a neck size die. Then you would have to re-set your FL die to better fit the fired case, particial re-sizing.

How do you throw powder gharges? You might be getting some loads to far under a min chg and not getting the pressure up. I have one powder measure that I have to watch to be sure powder doesn't hang up in the drop tube. Light chg this time, heavy next if I don't watch. I see primer's backed out in my light cast rifle loads all the time. If it was to much headspace what would happen is that the case and the bolt face would re-seat the primer but after a couple firings the case would show a bright ring around the case head where sepertaion is starting. If you see a bright ring, believe it is headspace. I've tried the bent paper clip a bunch of times and can't feel the seperation yet I knew it was there, I can see the ring! You don't say what case this is either. If it's a belted or rimmed case, it could be a sloppy chamber. In that case particial re-sizing will fix the problem. But it is probably still not headspace. Belted and rimmed cases do not headspace on the shoulder of the case and what may at first appear to be headspace is really a sloppy chamber with correct headspace.
 
well the more im reading around i think neck sizing is the way to go for me. both my guns im reloading for are bolt actions. one in .204 and the other in .243. neck sizing should get rid of my headspace and overworking the brass issue anywyas. until its time for a fl size after a few firings. then i will worry about setting up my fl die with a case mic. but neck sizing should get me by quite nice for a while right? or im not sure now if i even have a need for the case mics anymore if just neck sizing? next question, should i be neck sizing or full sizing new brass out of the bag, usually winchester brass.
 
I have a Lee collet neck sizer for my 243 and like it real well.

Your hung up on maybe having a headspace problem. Go to a gunsmith and have it checked! I can't really see a need for a case mic at all. Have one in 25-06 that I don't use. It was a gift. I had a terrible time with it probably because I couldn't find a need for it! If the shell fits the chamber properly I don't care what size it is. If I start seeing indications of head seperation, I know I have a head space problem and can fix it with neck and particial sizing. What I can't do is measure the inside of my chamber other than to measure a shell fired in it. Then if you got the shell out in the first place, it's not exactly the same size anyway, it's something smaller.

It's kinda like pressure. As long as it's safe, who cares what it is? You can't measure it anyway!

EDIT: Oh oh, I forgot. You could cast a chamber to measure it.
 
Last edited:
Back
Top