Dusty Stevens said:Mine is a .273 and i still turn necks. You need to at least skim cut em to get em consistent if youre talking about a competition rifle
IMO you're clearance is perfect. I think what Dusty was saying is that he turned for concentricity..not to create more clearance. I don't like to run any tighter than .002" clearance, but some do.Ram said:What is the minimum neck clearance for a no-turn chamber. A loaded round I'd like to use is 0.270", but the only in stock reamer I can find is 0.272". Is this sufficient clearance, or should I order another reamer?
Ram said:
What is the minimum neck clearance for a no-turn chamber.
mikecr said:For me, 2thou is plenty of clearance, and not excessive.
I would go with the .272, no problem.
For you:
If concerned about safety in it, any neck clearance at all is enough. Of course it's on you to verify this & keep your chamber/ammo clean.
If concerned about accuracy in it, well that's always a balance.
Where you make crooked ammo, tighter clearances lead to chambered tensions. So you could open the clearances to alleviate this and maybe shoot better. Depends on how well you can maintain consistent brass with larger clearances.
On the flip side, where you make straight ammo, you can get away with tighter clearances and brass that lasts a long time with little effort.
That's the balance, and it tips toward the cartridge design and your reloading abilities.
So what's the cartridge?
Ram said:What is the minimum neck clearance for a no-turn chamber. A loaded round I'd like to use is 0.270", but the only in stock reamer I can find is 0.272". Is this sufficient clearance, or should I order another reamer?
.276 I would think is the absolute minimum for a no-turn chamber.
I assume you're talking about a .243. Normally .003 neck clearance is considered the bare minimum for proper bullet release, anything less will give you problems. So .243+.015+.015 +.003= .276 and you're still running the risk of some of the thicker necks that are around .016-.017 .
You're right at the point where you can buy a new reamer for around $140 or a new neck turner for about $110 https://www.youtube.com/watch?v=ZFkV2thFL5U
Good luck,
Joe
Thank you Mike! I knew you would.mikecr said:I use fitted necks in a 6.5wssm. That is, 1thou total clearance(max)(fully within springback of my brass). No problems at all.
A chamber doesn't cause high pressures, or pressure 'problems'. We do.