Used brass in new barrel

[lapua]

And another

[No i deer]

4 or 5 times fired brass used in a new barrel,5 shot group with 184gr hybrids

 

[baldie]

Lets de bunk a few myths shall we ?

Virgin brass is NOT SAAMI spec. Its smaller than it. Thats so it will fit in ANY rifle.

Most dies won't size back to "SAAMI spec" either. Even the best makers seem to have trouble even getting them the right length, never mind to spec these days.

Brass will spring both ways.

Using brass fired in a factory rifle, then sized to fit a custom barrel is asking for trouble. Factory chambers are never concentric, nor minimum SAAMI spec.

I've seen it so many times in the shop. People coming back with an expensive custom rifle i've made them. " Its won't chamber these cases, there must be summit wrong with the headspace"

No, you shagwit....youve put your old ten times fired brass from from your Howa/rem/CZ through it...

You put that which promotes growth and vigour in, you will get that which promotes growth and vigour out.

New barrel, new brass.....every time.

[baldie]

15 hours ago, redding said:

No I did not specify any chamber, its a Lowther Walther barrel and is being made to fit a Tikka T3 in .308.

My thinking was that a FLS case would be the same dimensions as a case from an unfired factory round!

No. Most definately not.

The unfired round will be made from brass that is smaller than SAAMI spec, ensuring it will fit in any chamber.

FLS will only take it back near to SAAMI, or on it, if you are lucky.

Brass work hardens, which is why we anneal the necks.

You can only push the webs back as far as the dies will allow, and sometimes that isn't enough to chamber the case.

[ds1]

tell me about it Dave.......just bought 340 pieces of new Lapua 338 ammunition for my new barrel........my wallet is now on a defibrillator......the kick in the nuts is the 500 or so pieces of once fired 338 Lapua cases sitting on the shelf that won’t chamber in that barrel (Krieger). 

The cunning plan in future is for Craig to order a reamer from Mr. Kolbe so we can both use the same reamer and hopefully avoid future jam doughnut ups.

[Ronin]

Dave- If Craig needs a 338 reamer I have one he may borrow when the time comes 

 

 

[Catch-22]

It is precisely for this reason that I own all my reamers.

[ds1]

Hi Andy, many thanks for the kind offer to lend me a reamer . Atb David 

[redding]

No I did not specify any chamber, its a Lowther Walther barrel and is being made to fit a Tikka T3 in .308.

My thinking was that a FLS case would be the same dimensions as a case from an unfired factory round!

No. Most definately not.

The unfired round will be made from brass that is smaller than SAAMI spec, ensuring it will fit in any chamber.

FLS will only take it back near to SAAMI, or on it, if you are lucky.

Brass work hardens, which is why we anneal the necks.

You can only push the webs back as far as the dies will allow, and sometimes that isn't enough to chamber the case.

Hi Baldy

Thanks for the help, I know you re an expert, just tried once fired FLS brass in new chamber and it fits without any resistance, so I reckon I had a bit of luck!

Regards

Redding

 

Edited September 25, 2019 by redding
missing words

[redding]

Thanks to all for the helpful comments

Regards

Redding

[baldie]

Thanks Andy, i have a SAAMI and also a CIP .338.

This problem rears its head more in the .338 than any other cartridge.

Usually because the "once Fired" Mil stuff is RUAG, and its very hot. The brass is also very thick, which usually means you can't shove it back far enough to chamber [web thickness]

Dont get me wrong, a lot of fired brass WILL chamber in a different gun, but its very dependant on the cartridge, and just how thick/long the web is.

A good example being my own 6.5 creed. The norma brass i'm using, has seen 3 barrels now, lord only knows how many cycles its had, but I did chamber all the barrels, and know they were all absolutely true, which helps.

[No i deer]

That's why then Dave.

Neil Mckillop did both mine so thats why my brass was good for both chambers

[redding]

What does this mean?

On a new Hornady unfired factory .308 round, the case measured 1.617 from head to datum line on the shoulder.

After firing in new barrel the case measured 1.618

Is the fact that the case only stretched by 0.001 a good or bad thing, this once fired case still chambers without resistance.

[ds1]

My 2p. In basic terms what you described is good. 1 thou expansion is good in a bolt gun - Ideally resizing would return it to 1.167” again ( or 2 thou below that in a semi-auto). 

To muddy the waters however, what the measurement gives you is one linear measurement that try’s to describe case expansion in the chamber and subsequent contraction that happens in all directions.

Arguably its the most important measurement as if the shoulder is pushed back too far ( say  1/10”) you can start getting into case head / web separation  and all the nasty consequences as the case tries to expand linearly beyound it’s failure point ( on firing first pressure shoves the primer back from the primer pocket to the bolt head until pressure shoves the case back against the bolt head - this is why some importance is given to reading ejector marks, flat primers etc - sort of like tea-leaves).

 

 

[redding]

57 minutes ago, ds1 said:

My 2p. In basic terms what you described is good. 1 thou expansion is good in a bolt gun - Ideally resizing would return it to 1.167” again ( or 2 thou below that in a semi-auto). 

To muddy the waters however, what the measurement gives you is one linear measurement that try’s to describe case expansion in the chamber and subsequent contraction that happens in all directions.

Arguably its the most important measurement as if the shoulder is pushed back too far ( say  1/10”) you can start getting into case head / web separation  and all the nasty consequences as the case tries to expand linearly beyound it’s failure point ( on firing first pressure shoves the primer back from the primer pocket to the bolt head until pressure shoves the case back against the bolt head - this is why some importance is given to reading ejector marks, flat primers etc - sort of like tea-leaves).

 

 

Thanks

2 out of the 3 rounds fired have very slight (horseshoe) extractor marks

The 3 fired case measurements are: 1.619, 1.619 & 1.617.

The rounds are factory Hornady .308 150grn SST.

[KABOOM]

get the barrel home.will the old brass chamber with no pressure? Should it not chamber resize in stages until it does.