Need loaded neck diameter of 6.5x284 (140 class bullets and new unturned Lapua brass)

[ccooper]

New rifle coming soon and I would like to go ahead and order my bushings. Thanks

 

[VaRandy]

Maybe .2945. You should know your neck side in your new gun first.

 

[johnfred1965]

My old brown box Lapua measures right at .292. Happened to have some that weren't trimmed. They are usually very consistent, but I tend to shave a thou or so off to make sure! Wish I could help with the blue box, but I bought enough of the old stuff to shoot out 2 more barrels.

EDIT:that was with a Lapua 139 scenar, they might run a few tenths small

 

[hogpatrol]

I'm using Lapua, unturned with Berger 130 HVLDs and using a .292 bushing. Loaded round is .2940.

 

[Tucker65]

New Lapua brass with a Berger 140 vld hunting measures .2932 on my loaded rounds. These are new unturned necks also.

John

 

[VaRandy]

These guesses mean nothing until the poster gives us the chamber neck size.

 

[johnfred1965]

These guesses mean nothing until the poster gives us the chamber neck size.

Perhaps the OP has a no turn neck, and is simply looking for the right bushings for neck tension. He did mention he wanted the measurement on unturned brass.

 

[Autoverminator]

.294 with a 142 smk stuffed in the hole.

 

[VaRandy]

You do understand the neck tension can be perfect and you still blow the gun up if the chamber neck is not known?

 

[ImBIllT]

You do understand the neck tension can be perfect and you still blow the gun up if the chambered neck is not known?

Hopefully a person asking for a measurement of unturned brass does not have a tight-neck chamber. If his neck is not a tight-neck, then his neck diameter does not matter, and all he needs to know is really diameter of the loaded round.

If he has a tight-neck, then the diameter of someone else's loaded round is immaterial. He only needs to know what the neck diameter of his chamber is, and how far under that measurement he wants to go.

 

[VaRandy]

"Hopefully" is not good enough to me. For him to be asking the question does not give me confidence he knows his weapon.

 

[ccooper]

Hopefully a person asking for a measurement of unturned brass does not have a tight-neck chamber. If his neck is not a tight-neck, then his neck diameter does not matter, and all he needs to know is really diameter of the loaded round.

If he has a tight-neck, then the diameter of someone else's loaded round is immaterial. He only needs to know what the neck diameter of his chamber is, and how far under that measurement he wants to go.

Thanks. This ^ was my thinking exactly.

Perhaps the OP has a no turn neck, and is simply looking for the right bushings for neck tension. He did mention he wanted the measurement on unturned brass.

And this ^!

"Hopefully" is not good enough to me. For him to be asking the question does not give me confidence he knows his weapon.

VaRandy...I wouldn't have ever asked for other peoples neck sizes if my gun was for turned brass. It's no turn with .297 neck and I ordered a .292 bushing for now to get started. Thanks everyone for the help.

 

[T-shooter]

Just because it's Lapua, doesn't mean the neck wall thickness will be consistent. If you start turning them, you will see that most will have a thick and thin side. It could vary .002-.003". Here are some that I turned and you can see that there is not 360° contact with the cutter using a light cut. Even if they don't cut 100%, at least the heavy side is trimmed and much closer to being concentric.

 

[6MMsteve]

I just turned some brown box65284 and I had to go down to .0142 to clean them up my fired neck od is 297 more like I would say 298 the 262 bushing that you are starting with sounds like a good start. that be where me startin but I will not be shootin comp just plinkin and maybe steel maybe some paper at 1000

 

[6MMsteve]

I may have to go down to 290 I don't know but It's no big deal to me, if your planning on bein in Comp ask alot of questions on here someone will help you I'm sure, It's nice to have help good help, myself I need help because I have a disorder cannot focus but I fight thru it

 

[Clucknmoan]

I turn my lapua necks down to .0145 to clean them up, neck down with a .290 bushing, then expand out to .0015 tension. Loaded necks are .2935

 

[Shynloco]

I turn my lapua necks down to .0145 to clean them up, neck down with a .290 bushing, then expand out to .0015 tension. Loaded necks are .2935

Cluckn,

May I suggest you add a step prior to turning the brass and that is to running the brass through an expander mandrel (if you aren't doing that already). I've found that step helps overall concentricity and that any chance of a slightly fat side is removed. But I will say I do not agree with an earlier post that suggested Lapua brass has a fat side. Just a thought.

Alex

 

[Clucknmoan]

Cluckn,

May I suggest you add a step prior to turning the brass and that is to running the brass through an expander mandrel (if you aren't doing that already). I've found that step helps overall concentricity and that any chance of a slightly fat side is removed. But I will say I do not agree with an earlier post that suggested Lapua brass has a fat side. Just a thought.

Alex

Completely agree, push the inconsistencies to the outside. I didn't mention this but I do it before turning

 

[T-shooter]

I had to go to .0125" on the Lapua necks to get most at a 85-90%+ cut. They are expanded with a K&M mandrel and I use the K&M neck turning tool. I found one of the boxes, .308 Lapua #4PH7217 and the lot number is #P00729001. The last Hornady Match .308 I bought cleaned up at .014". Yet again, I had some before that wouldn't at .0125". The lot before these were crooked and had to be annealed to eliminate most of the runout. Lapua is better quality than most but it depends on a lot of things, how long they run the dies before tolerances run too high and they are replaced. For instance, the same part number #30501 of Hornady Match .308 bullets, very different from one lot to another.

 

[jmatters]

Cluckn,

... I do not agree with an earlier post that suggested Lapua brass has a fat side. Just a thought.
Alex

I'm almost through turning 200 blue box 6.5x284 Lapuas to .145, and I have say that 80% of them at least have low spots untouched by the cutter. Does that qualify as a thin side? Possibly a semantic question more than a brass question.