Lapua case necks too thick for my rifle

[Mikecr]

If your barrel was chambered as tight neck, that is usually engraved on the barrel.
Like "260Rem (.290 neck)"

After firing the factory ammo, what do those unsized necks measure?
What do loaded necks with your unturned Lapua brass measure?

 

[lancetkenyon]

I know all that. What I must have dilly danced about was, does Lapua make .284 brass thinner than 30 cal brass?

Not that I am aware of. If you want thinner, get .260 Rem brass and neck UP.

 

[MagnumManiac]

My 260AI is a custom reamer 'no-turn neck', but my own Lapua brass requires turning to fit comfortably. If I don't turn, clearance is less than .002" by a couple tenths. I measured with Remington brass…
If you ever want thinner brass in the necks, neck smaller brass up, I do this with several of my custom cartridges to avoid turning necks, .003" chamber clearance is absolute minimum and should never be less than .002".

Cheers.

 

[setter]

If your barrel was chambered as tight neck, that is usually engraved on the barrel.
Like "260Rem (.290 neck)"

After firing the factory ammo, what do those unsized necks measure?
What do loaded necks with your unturned Lapua brass measure?

Nothing engraved on the barrel to suggest a tight neck. That doesn't mean it isn't of course. I will be measuring the necks of fired brass, and loaded factory brass, and hopefully figure out what would be a reasonable clearance. However, I hope to find out if there is high quality brass that I can get that doesn't need to be neck turned to fit in the chamber, and that was the main reason I began this post. But I will deal with the Lapua brass I have so I can be able to use it, and learn more about another aspect of reloading that is all new to me. If I can't get good information on other brass that doesn't need to be neck turned, then I will just stick with the Lapua (although it appears to be the most expensive) and find a better neck turning tool. I don't want to have a bunch of different brands of brass with slightly varying dimensions to mess with and keep track of.

 

[Mikecr]

I will be measuring the necks of fired brass, and loaded factory brass, and hopefully figure out what would be a reasonable clearance.

Factory fired/unsized necks
Lapua unturned/loaded necks

 

[Varmint Hunter]

You need to KNOW the chamber's neck diameter. Ask the gunsmith for the reamer specs. Your loaded ammo could fit and still be unacceptably tight. Normally, a loaded round should have .003"-.004" of clearance in the neck for proper bullet release.

 

[Kimber7man]

What is the neck diameter of a fired piece of brass?

 

[cape cove]

What is the neck diameter of a fired piece of brass?

That is what I would do. Add appx .0005-.001 for spring back and it should give you a decent sense of your chamber neck size. JMO

 

[setter]

That is what I would do. Add appx .0005-.001 for spring back and it should give you a decent sense of your chamber neck size. JMO

I will measure the fired piece of brass and do as you suggest. Once I get a bullet puller I may also see if I can try turning the brass in very small increments, seating a bullet (no primer), and see if it will fit in the chamber; if not, pull the bullet and turn again, until it goes in.

 

[setter]

Appears this rifle does have a tight necked chamber.
SAAMI for 260 Remington neck diameter is 0.297 loaded

Brass neck outside dia.:

Barnes loaded 0.2920
Barnes fired 0.2930
Lapua loaded 0.2945 (would not chamber into rifle)
Lapua fresh, empty case 0.2925

 

[Mikecr]

I would not like necks so thick, either 14thou for Barnes, nor over 15thou for Lapua.
And the barrel finisher should have engraved "Tight Neck .292" on there..

 

[setter]

I would not like necks so thick, either 14thou for Barnes, nor over 15thou for Lapua.
And the barrel finisher should have engraved "Tight Neck .292" on there..

Mikecr, I assume you did the math and I thank you for that! I was curious and actually measured the thickness of the brass at the neck for two individual cases. Barnes: 0.0143, Lapua 0.0153. What case neck thickness would you recommend?

 

[Mikecr]

I accept 12-13thou, and turn necks to and within this range.
Here I get reasonable tension with low variance.
That's just me. I turn necks for everything -provided it does not contribute to excess neck clearance, which I consider >3thou.

Turning necks to 13thou would give you .290 loaded necks for 2thou clearance.
Turning necks to 12.5thou would give you .289 loaded necks for 3thou clearance.
Turning necks to 12thou would give you .288 loaded necks for 4thou clearance.