Headspace questions

SL1

New member
How new are the primers?

I had a batch of CCI primers around for about 20 years. When I loaded and fired them, one showed a black ring on a load I was working-up at a charge weight that should not have been more than 25,000 psi. So, it really made me think.

Eventually, I deprimed and took a good look at the primer cup. There was a fine, but distinct crack from the edge up to the radius, which caused the leak. No brass or steel cutting, probably because it was a low-pressure load. The same crack in a full-power rifle load would probably have looked like the OP's pictures.

I think MY primer problem was that they were old, and probably had not been properly annealed during manufacture, so that they embrittled with age. So far, only one has failed. But, I have relegated them to 16,000 psi loads, so that isn't saying much.

SL1
 

243winxb

New member
Neck sizing only, will take about 3 or more firings for the brass to fully form to the chamber. When a bolt action starts to close hard, you know your at maximum cartridge headspace. For Auto, pumps, levers, break actions, always full length resize. :)
 

243winxb

New member
Marks on the Case Mouth?

Jason, did the brass come from new Winchester factory ammo? Or did you buy new empty brass and reload it?
 

Brian Pfleuger

Moderator Emeritus
Those marks look exactly like the crimp on Winchester factory ammo.


(You don't have to always full-length size for break-action guns.... I treat my Encore Pro Hunter just like a bolt gun.;)
 

243winxb

New member
If this is the firearm leaving marks on the case mouth, see the gunsmith that chambered it. If brass came from factory new ammo, then dont bother.
I have a chance to purchase a FnH spr action in a hogue overmolded stock along with a shilen (unattached) select matchgrade barrel unturned. Both are new items purchased by an older gentleman that has lost his interest in this build due to health issues..
Having it fitted to the rifle is going to run around 350-400 I think? Will truing the action and the barrel show a significant difference in accuracy?How much will having the barrel turned cost? What would a fair price be? And, your opinions of potential accuracy from this weapon? I will be reloading the rounds if purchased.
 

wncchester

New member
"For Auto, pumps, levers, break actions, always full length resize."

"Always"? That's a loong time!

I have two boxes of ammo for each of my 336's; .30-30 and .35 Rem. I only shoot them a few times a year for scope check and hunting so they don't get a lot of firing. When one box is empty I go to the next and eventually get around to reloading the empties. I have ONLY Lee collet neck sized my Remington brass for both cartridges for over twenty years with absolutely no chambering problems nor have I yet had a case split.
 

F. Guffey

New member
“Can a casing with excessive headspace be resized back to SAAMI specs?”

Most will spend the rest of the week answering the question, but, I am not most, I am not even in the minority, I am out there all by myself because I still do not know how head space and a case with too much of it are related. My dies and presses have threads, that makes my dies and presses adjustable, I adjust my die to the shell holder in the press to off set the effect head space will have on the case when fired: therefore head space is in the chamber, head space can be off set with the length of the case.

Starting over: To do that I have to ask a question. Why don’t you know the effect the chamber will have on the case? If you have the L.E. Wilson case gage, why didn’t you measure the length of the case from the shoulder to the head of the case before you fired the case the first time?. The length of the case from the datum (shoulder can be measured, in thousands with a Wilson case gage. The instruction say to use a steel rule as a straight edge across the top of the gage to determine the gap, me, I use a straight edge and a feeler gage, Advantage? I measure the length of the case from the datum (Wilson case gage) to the head of the case, I fire, then measure again (a-b=c) when a is length of the case before firing and b is length of case after firing AND IF THE RELOADER CAN KEEP UP With THE LENGTH OF THE CASE is from the head of the case to the datum (shoulder).

Then that brings up the only measurement you listed, 2.491, that confuses most, that number has nothing to do with head space, 2.491 is case length, normally there is a + and –, as in max 2.494 and trim to, for the 30/06 that would be –.010 or 2.484.

You could join the ‘fire form' club, they chamber a round, fire it then extract the case upon which time they become fire formers. Me, I measure the length of the case from the shoulder to the head of the case first, then fire, then determine the effect the chamber had on the case when fired as in A-b=C after firing I then VERIFY by measuring again, and I repeat, I use a straight edge and feeler gage, others use their finger nails , and that puts me ‘out there all by my self’.

And I measure the length of the chamber first to determine the effect the chamber WILL HAVE on the case when fired without a Wilson case gage.

“And in case you're wondering, I failed to check the head spacing on some 30-06 brass before reloading” I believe you should know the length of the chamber before attempting to size cases for your chamber, again, measure the length of the case before firing, fire, then measure again, and do not allow yourself to get locked up in the ‘ol’ snap back, jump back spring back thing. And Sammy's, there is Sammy's chamber and there is your chamber, sizing to Sammy's chamber is busy work.

F. Guffey
 

F. Guffey

New member
And for the length of the chamber, from the bolt fact to the beginning of the throat, it is possible to measure the length, it is possible to measure the length of the chamber from the bolt fact to the shoulder (datum), I will never understand why measuring the length of the chamber is never considered until after the case is fired and the reloader starts reloading.

F. Guffey
 

243winxb

New member
RCBS-Frequently Asked Questions-Sizing

(You don't have to always full-length size for break-action guns.... I treat my Encore Pro Hunter just like a bolt gun.
"For Auto, pumps, levers, break actions, always full length resize."

"Always"? That's a loong time!
Q. I see a Small Base Die Set listed for my caliber. Do I need these or should I buy a Full Length Die Set or Neck Die Set? How does each set differ?

A. The Small Base Die set is intended for use for ammunition to be used in auto, semi-auto, and lever action rifles so that the loaded round chambers and extracts easily. The Small Base Sizer Die sizes the case from the shoulder to the head of the case a couple of thousandths smaller than a Full Length Sizer Die. In certain calibers it also sets the shoulder of the case back a thousandth or two more than the Full Length Sizer Die. The Full Length Die Set or Neck Die Set is not normally recommended for ammo to be used in auto, semi-auto, or lever action rifles. The Full Length Die set is recommended for ammunition used in bolt action rifles, particularly for ammunition to be used for hunting. The Neck Die Set can also be used to produce ammunition for use in bolt action rifles. The Neck Sizer Die sizes only the neck of the case so it will hold the bullet firmly. It does not size the body of the case nor does it set the shoulder back. Neck sized cases will usually chamber for three or more firings, depending on the powder charge and chamber dimensions. However, over a period of time, a slight drag will be noticed when the bolt is locked. At this point, cases will need to be full length sized and the shoulder set back so they will chamber and extract easily.
What RCBS has posted, is what i tell new people just starting to reload. I know from experence that standard dies will load most all firearms, evem M16A1. And yes, neck sizing will work for 1 loading in a machine gun. Others that are neck sizeed will soon or later need FL sizing.
 
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