THE HANDLOADING BENCH
308 Winchester Rides Again Part 4 By Laurie Holland
Seating dummies for the five ‘heavies’ shows the 2010/11 barrel was throated a bit too short. The bullet base positions are marked on the cases. Left to right: 200gn SMK; 210gn SMK; 208gn A-Max; 210gn Berger BT and VLD.
Twist rate and ‘freebore’ permutations are almost endless but I reckon there are four basic forms: two ‘specialised’, two ‘multi-purpose’.
The specialised versions are 1-13 or 1-14 twist rate plus a short throat optimised for a single or small group of 155gn bullets. That’s what you get in a TR, Fullbore or Palma sling-shooting rifle and some F/TR competitors have stuck with the format.
The other extreme is a 1-10 twist rate barrel throated out to suit 215 and 230gn Berger Hybrids. Other, shorter bullet designs may still work in it, but have to make a long jump into the rifling.
In between, multi-purpose configuration #1 uses 1-12 rifling twist and is throated for the more efficient
75
155gn bullets seated shallow in the case and longer bullets up to and including Berger’s 185gn BTLR and 190gn VLD seated near optimally, likewise the 190/200gn SMKs. (Change the twist rate to 1-11 and you can handle the 210gn bullets too, but they’re seated a bit deep.)
Multi-purpose configuration #2 has a 1-11 twist rate barrel throated to suit the 185gn Berger BTLR seated shallow, the 200-210s optimally. Opt for 1-10 rifling twist and this set-up handles the 215gn Berger Hybrid / 225gn Hornady HPBT set a little deep, and might just cope with the 230gn Berger Hybrid. My old barrel, used for the test loads shown below, had the ‘multi- purpose #1’ throat but allied to 1-10 rifling twist rate.
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