Is the number of times fired all that important with cases?

[Laurie]

Ed,

I do love your posts. Actually, I've rather a lot of HXP 303 brass, some new and with original staked-in primers from demilled Mk7 ammo. (Good stuff!), but no 303 rifle for many a long year. Shame that we're on opposite sides of the Atlantic or you could have it.

I think the other factors in keeping 303 brass alive and healthy is neck sizing and keeping pressures nice and low, like under 40,000 psi. I don't think I ever wore 303 brass out until necks split, and I'd usually got myself another rifle and started with new brass before that happened. That was in chronological order a pre WW1 BSA match version of the long 'Territorial Pattern' rifle with both service and folding twin-zero target aperture rearsight; an Ishapore WW2 SMLE; Fultons built inter-war era target SMLE with heavy BSA barrel and all the bedding tricks (for the old Service Rifle (b) discipline); ordinary WW2 No.4; and a very good shooting Ross MkIII.

 

[Laurie]

Not sure I understand that correctly. I would have assumed those that get chambered close or to the same position would have a LOWER failure rate.
In a .222 Rem (easy on brass) I have a shell holder bolt face. I position every cartridge the same way 'Headstamp Up'. Or as close as my eyes can determine. I have no idea if this has added to the longevity or not. [M61]

My thinking here is that if the case bends the same way each firing, it puts more stress on one particular area. As Bigedp says, separation results from the same process as bending a thin sheet of metal repeatedly at one point. But ... maybe not in a cartridge case / chamber situation?

I don't know if you'll improve case life by indexing your 222's cartridges in the chamber, but it certainly won't harm precision as any slight deviation from 100% concentricity in the chamber / fireformed case will be negated.

 

[savagedasher]

I read and hear all the time about how shooters keep their cases segregated by weight, volume, times fired, etc.

I've been wondering how important the "times fired" factor is if the others are equal. If cases are all of the same head-stamp, weight, volume, and have been annealed, does it truly matter how many times they have been fired?

I realize that firing work hardens the brass as well as a certain amount of thinning in the body but for accuracy, does it matter if there's no sign of case head separation (measured thickness)?

Just curious.

I segregate my cases by volume and times fired. Weigh of the case and head stamp has no bearing on volume.
The dies I use don't work the brass .I have shot them 27 times without annealing.
Two weeks ago I was the first to hit 15 5'' gongs in a row at 600 yds. Last weekend I shot my two personal best IBS type targets at 600yds one was 1.625 the other was 1.059 .
So my answer is no to what you ask. Larry

 

[artbosco]

A lot of national short-range Benchrest competitors throw their brass away at the end of the week following the matches. Usually about 15 pieces.

 

[savagedasher]

A lot of national short-range Benchrest competitors throw their brass away at the end of the week following the matches.

With practice and if they use the same gun in light and heavy gun they could have as many as 20 reloading on the brass . I never seen any annealing. Larry

 

[Laurie]

A lot of national short-range Benchrest competitors throw their brass away at the end of the week following the matches.

With practice and if they use the same gun in light and heavy gun they could have as many as 20 reloading on the brass . I never seen any annealing. Larry

But take into account that the brass working per firing / sizing cycle is minimal on a typical short-range PPC bench gun. 0.001-0.0015" neck expansion in the chamber and 0.003 or 0.004" reduction from that point before bullet seating. For ammo loaded on the firing point, necks are only under tension holding a bullet for minutes before firing unlike cartridges loaded at home for other disciplines, some of which may sit around under tension for weeks or months before use. (A different if related subject.)

 

[M-61]

QUOTE FROM LAURIE:

...For ammo loaded on the firing point, necks are only under tension holding a bullet for minutes before firing unlike cartridges loaded at home for other disciplines, some of which may sit around under tension for weeks or months before use. (A different if related subject.)....

To take this to an extreme: Due to the recent shortages I found myself digging deeper into closets, shelves and drawers. Found 40 Rem cartridges loaded in the late 70's I had loaded. 222 Rem brass, necks turned, 52 gr Sierra HPBT, 20.2gr. 4198
All 40 rounds had their necks shrunk so tightly around the bullets one could EASILY see the depth the bullets were set into the neck. Of course this distinct line disappeared where the BT started. No splits but that line was very obvious. There was no corrosion involved (nothing growing out of the necks). I elected not to fire them and pulled the bullets. Other than that visual super squeeze I saw nothing unusual. The bullets pulled the same as any others.( meaning no high amount of effort that I could feel....but NO way for me to measure)
Laurie, I think I took your weeks-months to decades. Funny (odd), in old ammo I have collected, some from the late 1800's I have not seen this line at the neck....splits sure....but no visual line.

 

[Laurie]

Interesting (re 30 odd year old handloads)! If you'd fired any, I wonder if some would have failed at the join? (Maybe taken the top of the neck into the barrel still wrapped around the bullet? Wise choice to pull them, I'd reckon.)

Old 303 Cordite charged military cartridges often have a high percentage with split necks due to tension on bullets. But they weren't annealed before loading as is the norm in nearly everything else. (Cases were formed and primed as per normal but without the shoulder / neck top section. The charge which was in the form of a bundle of case length rods was inserted, then the shoulder + neck cold swaged before bullet seating took place.

 

[243winxb]

Primer Pockets - How many firings?

It would be good to know how many firings , if primer pockets are getting loose. Case primer pockets getting loose in five reloads or fewer = High Pressure or Soft Brass.

 

[bigedp51]

Interesting (re 30 odd year old handloads)! If you'd fired any, I wonder if some would have failed at the join? (Maybe taken the top of the neck into the barrel still wrapped around the bullet? Wise choice to pull them, I'd reckon.)

Old 303 Cordite charged military cartridges often have a high percentage with split necks due to tension on bullets. But they weren't annealed before loading as is the norm in nearly everything else. (Cases were formed and primed as per normal but without the shoulder / neck top section. The charge which was in the form of a bundle of case length rods was inserted, then the shoulder + neck cold swaged before bullet seating took place.

Laurie, you forgot the best part, you didn't tell them what cordite was made of when it first came out, 58% nitroglycerin, 37% nitrocellulose and 5% petroleum jelly. And the reason you kept using it was because you didn't want to pay royalties to Alfred Nobel, now you tell them what a spag bol is and why you put it in your ammunition.

 

[Juma]

Annealing your brass and not stoking super hot loads.Amazing how many times you can use your brass. Some dudes get 20+ from 22 cases. Annealing is the secret because it delays brass hardening . You notice it when you FLS.