Set-back and rechamber

[Charlie-NY]

I'm finally getting around to rechambering a heavy bench rifle in 6.5x284. The rifle was built off a Remington single shot 40X action. The current bbl is a 28" Lilja with a heavy bbl (forgot the profile but it has plenty of full diameter barrel shank.)

I opened a new box of Lapua 6.5x284 brass and sunk a Berger 140gr Elite Hunter into the neck with the boattail/shank junction just above the case's shoulder/neck junction. I measured the neck near the case mouth and get a consistent .290". Measurements lower on the neck are smaller by a few .001s.

My smith has the following reamers in the shop:
6.5 - .284 Norma / .295 neck / .220 fb
6.5 - .284 Norma / .291 neck / .210 fb

I really don't want to neck turn but could if there was a compelling reason to do so. Which reamer would you recommend and why?

 

[WSnyder]

Simple. With your two choices.
No turn =.295nk reamer
Turn =.291nk reamer

 

[SKWERLZ]

I’d go with the no turn reamer.

 

[Charlie-NY]

I normally look for .003" of bullet release, that's why I'm uncertain as to which way to go. Any issues with a .005" of bullet release?

Do necks tend to get thicker, thinner or remain the same after multiple firings?

 

[Tommie]

I normally look for .003" of bullet release, that's why I'm uncertain as to which way to go. Any issues with a .005" of bullet release?

In theory (and maybe reality) a reduction in case neck life.
Meh.

 

[WSnyder]

Any issues with a .005" of bullet release?

No, not at all. I’d rather have extra in a no turn rather than too little. IMO .003” is too tight in a larger cartridge.

Do necks tend to get thicker, thinner or remain the same after multiple firings?

Brass tends to migrate into the neck shoulder junction. Larger neck can’t hurt here either.

 

[Charlie-NY]

Thanks for the feedback guys. I'll take your advice and get the .295" neck. I've neck turned for a few rifles but believe that high quality brass negates the need to turn necks for my needs. I only compete against myself, as I'm primarily a hunter with an interest in precision reloading/shooting.

 

[284winner]

Reamer #1

 

[Clancy]

Thanks for the feedback guys. I'll take your advice and get the .295" neck. I've neck turned for a few rifles but believe that high quality brass negates the need to turn necks for my needs. I only compete against myself, as I'm primarily a hunter with an interest in precision reloading/shooting.

I shot this about 9 am with some 6BR brass turned for a .268 chamber……. In a .272.

Sleep well with the .005 clearance.