What 284 Freebore?

[accuracyman]

I need a 284 reamer that will shoot either a 180g Berger VLD or the 180g Berger Hybrids. I have researched and found answers between .188" to .235". The most common answer for 180g Berger VLD's is .220". My confusion is looking at a reamer print it shows a dimension for the LEAD or Freebore which is the area in front of the neck AFTER the 45 degree taper from the case neck dimension to the freebore dimension that accepts the straight portion of the bullet before the 1.5 degree taper. When folks talk about having a .220" freebore are they including the 45 degree gap where the chamber tapers down from the neck portion of the chamber to the lead portion. According to most prints for a 284 that amounts to .016" extra "lead or freebore". So is the actual lead or freebore .220" or .236"? See the confusion? In my mind that extra .016" is truly more freebore but I'm uncertain that people are adding that in when stating they run a .220" freebore. I just want to make sure the VLD's stay above the neck/shoulder junction.

Thanks and look forward to your reply.
Kris

 

[furmaster]

Get a .220 for those bullets and don’t look back. I know a gunsmith who has a .220 freebore, .313”neck cut for Lapua Brass. He bought it from me when he chambered mine. If you are interested in a turn neck.

 

[furmaster]

Oh, to answer your question on lead and freebore print stuff, not sure. I just know .220 will nut those bullets.
Call dave Kidd at ptg and ask

 

[ShootDots]

My .284 Reamer has a .313 neck and a .235 freebore.. It handles everything but the 180 Scenars and the Berger 195's..

 

[Rogmay]

I also have a 284 with a 317 neck and a 231 freebore shoots the 183mk’s and the 180vld’s very well!

 

[Keith Glasscock]

To answer your question:

No, we are not considering the tapered section when we speak of freebore. The freebore that we are talking about is only the cylindrical section (about .2845" diameter for a 284).

Hope this helps

If it is of any value to you, I've been using a .218" freebore for 180 hybrids with good results.

 

[Grant G]

Another consideration when figuring freebore length is the freebore diameter, and lead angle down to the lands. If one person is using a .2850 freebore diameter, and a 0_-47-35 lead angle with a .200 freebore length, and the other is using a .2845 diameter with a 3_-0_-0_ lead angle with the same freebore length, then the two will be quite different in what they will chamber, and shoot.

 

[accuracyman]

Thanks for the reply guys....I didnt think the 45 degree area was considered when speaking about freebore. Thanks again...220 freebore it is.