larueminati
Member
- Joined
- Oct 25, 2017
- Messages
- 58
Very nice groups, some of the best i've seen from a Kimber. Nice work.
Nature Boy said:You give up some BC with the tangent ogive but you get seating depth flexibility for loading for short throat chambers and magazines.
According to Barnes these are the optimal velocity "windows" for the .30 cal bullets. Going with a MV of 2,750 fps and the 1,800 fps minimum, the 165gr should be effective in terms of expansion from 0 to at least 550 yards which is about as far as I'd want to shoot an elk or deer with a .308 Win.
.30 cal 150gr TTSX 2,000 fps > 3,000 fps
.30 cal 165gr TTSX 1,800 fps > 3,000 fps
.30 cal 180gr TTSX 1,500 fps > not tested
.3MOA said:1. Barnes' recommendation ... is that max for Varget is 44.5 gr (compressed) but you went a fair bit beyond that. Did you compensate for the shorter barrel ?
Is there info from Barnes I'm not aware of for shorter barrels ?
.3MOA said:2. I just got some Lapua 308 brass and it comes consistently at 2.007". I think (and I may be wrong) that the SAAMI spec
is at 2.015" but I think you mentioned sizing Lapua brass down .002" to meet SAAMI. What am I missing ?
The C.O.A.L listed by Barnes for the 165gr TTSX is 2.735" but I used 2.810" which is .075" longer so the pressure is reduced. Also, for the 84M, the bullet is way off the lands so lower pressure too. Barnes recommends at least .050" off the lands for their solid copper bullets to prevent a pressure spike as the bullet is engraved. The theory is that the bullet moves out of the case far enough to allow pressure to drop before it makes contact with the lands in the leade where the pressure can start to increase due to higher resistance.
I was referring to the location of the .400" datum (diameter) on the shoulder and not the overall case length. Trim length for .308 Win brass is 2.005". SAAMI lists the case length as 2.015"-.020" but most reloading manuals suggest a nominal dimension of 2.005" which makes a lot of sense.
.3MOA said:For the 0.002" case resizing, do you use a full length sizing die or a bushing die ?