Optimal Bullet Placement in Case?

As cases are shot the thicker shoulder area gets pushed into the neck which can create a " donut"
Unless....
You are shooting Remington or Winchester brass. They use the same thickness at the shoulder as the neck.
Which is why the 6SLR and 6.5SLR suggest using R-P or Win brass to avoid the nasty donut and absolute NEED to turn necks.
 
Weatherby has all kinds of 'jump' and it seems to work well for almost 80 years.

#1 is always the better choice JMO

Here is a pic. of the freebore on my .300Wby Mk V. Gobs of room to experiment with.
 

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I do my best to set my reamers up so that #1 is touching, giving me my max length at ~ 50% bearing surface in the neck.

I also don't typically size the full neck, only 50-75% depending, so the effective neck hold of #1 is also what I normally get even if the bullet is seated deeper like #2.

Case capacity change is usually negligible for me, load densities pushing 100% can be hard to get for my powder choices in my larger cartridges where OAL can be an issue, ie 300 RUM.

If you're committed to F-TR then find a smith that has the spec reamer designed for the particular bullet you want to run, or order your own even so your chambers will all be cut much more similarly. Neck/leade/freebore dimensions will be set for exactly for your bullet and brass.

 
I do my best to set my reamers up so that #1 is touching, giving me my max length at ~ 50% bearing surface in the neck.

I also don't typically size the full neck, only 50-75% depending, so the effective neck hold of #1 is also what I normally get even if the bullet is seated deeper like #2.

Case capacity change is usually negligible for me, load densities pushing 100% can be hard to get for my powder choices in my larger cartridges where OAL can be an issue, ie 300 RUM.

If you're committed to F-TR then find a smith that has the spec reamer designed for the particular bullet you want to run, or order your own even so your chambers will all be cut much more similarly. Neck/leade/freebore dimensions will be set for exactly for your bullet and brass.

I did just that recently!
thumbnail_image3 (3).jpg
 
Unless....
You are shooting Remington or Winchester brass. They use the same thickness at the shoulder as the neck.
Which is why the 6SLR and 6.5SLR suggest using R-P or Win brass to avoid the nasty donut and absolute NEED to turn necks.
Nice tip. Now to find them. Horrible brass. Just aweful ;)
 
Nice. What specs did you use on the reamer/ what bullet are you going to use?
It was the only 308 WIN reamer in stock. JGS tactical match with a short freebore of .070. SAAMI is .090. Neck .342. I plan to use Berger 155.5 FB in this barrel. 600yd FTR.

My CBI is a 308 match chamber. Berger 200.20X seated at 3.025. .003" off touch.
 
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