Throating reamers why and what for.

[Alpha1]

Throating reamers.
Why would you use a throating reamer is it to accommodate a particular bullet. What would prompt you to use a throating reamer. What advantage if any is there in having a longer throat as apposed to a standard reamer.
I looked at a 6.5x55 standard reamer side by side with a throating reamer. The throating reamer is nearly three times longer than the 6.5x55 neck. That's quite a long bullet.

[FredB]

Stop ring bullets or breach seating
Fred

[The Gun Pimp]

The 'throat' on a custom rifle/chamber can be adjusted with a throating reamer.

Example - take the 308 Win.chamber throated to suit a 150gn bullet. If you wanted to use a 200gn bullet, it would have to be seated much deeper into the case - thus compromising powder capacity. So increase the throat with a throating-reamer.

I tend to spec my reamers for the bullet I intend to use but a working gunsmith would need half a dozen reamers to cover all possible bullet combinations so a throating reamer and one short-throat reamer will do any job.

On factory rifles, the throats are usually long enough to take any bullet