Neck length

[Jcub]

I've been reloading for a .280 Ackley for the last few years, book trim length is 2.525".

I used a sinclair chamber length gauge and determined my average overall case length of 2.665".

So with that is my new trim length 2.662"?

That just seems really long.

 

[Rich Coyle]

If your loaded rounds go into the chamber easily, I wouldn't trim them shorter than they are or any shorter than absolutely necessary. Hornady did extensive testing and discovered longer necks give longer barrel life.

 

[Mikecr]

Forget book lengths, or the common notion of trimming all to shortest.

There are prices for everything, so best comes down to what you can manage. Heavy FL sizing will lead to lengthening that will have to be trimmed away as you go, and you don't want to run into chamber end.
On the other hand, tight clearance reduces carbon sooting/ES.
I like 5thou under chamber end, 10thou max.

It's not about barrel life. There is really no reason neck length would affect barrel life.

 

[Rich Coyle]

Mikecr,

Forget book lengths, or the common notion of trimming all to shortest.

It's not about barrel life. There is really no reason neck length would affect barrel life.

Apparently you have not heard the latest info. Loney, at Hornady, did lots of testing. Longer necks reduce barrel burning.

 

[Mikecr]

Would love to see how 'barrel life' was even defined, much less isolated to a single factor.
Do you have a link to the test?

 

[Bart B]

And barrel life calculations mean nothing unless they're all tested with the same objectives, conditions and standards. Match barrel life is often 1/10th to 1/20th that of combat service barrel life for the same cartridge.

 

[FearNoWind]

"Barrel life" ... a curious subject. First, you have to define "barrel". Is it the back of the chamber to the muzzle. Perhaps it's the free bore to the muzzle. Or, perhaps it's the portion of the barrel that is rifled. I define it as the portion of the barrel that controls the alignment of the bullet. So I consider nothing behind the free bore. I scope my bore every time if shoot and clean. I've never found excessive barrel wear resulting from OAL case length. So I'd suggest you not be concerned with a case that might have been trimmed a bit shorter than usual. Shoot and enjoy.

 

[Rich Coyle]

Would love to see how 'barrel life' was even defined, much less isolated to a single factor.
Do you have a link to the test?

You might check with Hornady. I talked to a retired company shooter.

 

[AZShooter]

According to your measurement, the end of the chamber is .140" longer than the brass. I would suggest your Sinclair tool is passing the end of the chamber and you are getting a false measurement. I think you are actually into the tapered part of the throat with the Sinclair tool.

I have seen some long chamber ends in some factory rifles with some as much as .050". Custom reamers are far shorter. Is this a factory rifle or a custom?