Fireforming 6mm BR Lapua brass


Feb 13, 2016
I purchased 200 pieces of Lapua brass recently, the same lot on both boxes. Did not want to use the expensive Bergers to fireform, so I am trying out 105 grain Vapor Trails for the first time, used Varget in .3 grain increments from 27.5 to 29.3 grains. I currently use 30 grains of Varget on the fireformed cases with 105 Berger Hybrids at my 600 yard matches. I tested the new Hybrids, since its a new lot and used 30 grains Varget, with seating depths of .005" jammed into the lands, .010" and .020" off the lands with fireformed old brass. No chrono was used this time. First picture is a cold bore, 3 fouling shots using .020" off the lands before testing.

Testing, .005" jammed, .010" and .020" off, not sure why the .020" off is not a one hole group like the 3 foulers since seating depth is the same, could have been me. Can restest another time at 600 yards.

Last picture is Vapor Trails 105 grain using new lot of Lapua virgin brass, 27.5, 27.8, 28.1, 28.4, 28.7, 29.0 and 29.3 grains.

Will choose at least three of those loads and retry at 600 yards. Why not try to fireform them while shooting at the match was my idea. Hopefully there is no vertical spread at 600.
Swapped out the seating stem for the VLD stem, package arrived yesterday. Let's see if the Hornady Match does not deform when seating using new brass which is a bit tighter than the fired brass. Will post the results later after testing at 600 when weather cooperates.
Ran a few tests yesterday evening @100 with the P 35 to verify velocity. Winds variable at 10-12 mph right to left. I chose 28.2 grains by what the previous target tells me and used 4 different seating depths.
Vapor Trails was bullets used, 3 rounds was jammed .005" into the lands, 3 at the lands, 3 at .005" off and 3 at .010" off. Seems that it likes .005 ( 3rd target) and .010" (last target) off with .005" as the best using Lapua virgin brass . 5 ES with the .005" off and 1 ES with .010" off. Velocity averages 2730 fps which is a mild load, my previous loads using 105 Bergers was 2825 fps with fired Lapua brass. For now my goal is to find a good load using virgin brass for the 600 yard match in March until all are new brass are fired before I'll tweak using Bergers. I'll be heading out tomorrow to test 600-700 yards using virgin brass. Will post results soon. I dusted off my old Caldwell, tied a small bull bag on it and packed the sides in tight using the L brackets, and the McMillian A-5 sits on it like a charm, snug and tight and It feels more stable than the Atlas bipod, I'll be using this Caldwell in future matches, been feeling comfortable with it yesterday.
By the way, I think I have put a little over 1200 rounds down the tube, did not keep a log which I should have. My thoughts are once the barrel is shot out, I'll have a Bat Machine custom action and a new heavy Bartlein barrel dropped in. Bat actions are a beast.
Overall the Lapua virgin brass seems pretty consistent to me.


  • test8.JPG
    65.4 KB · Views: 9
  • test6.jpg
    115.2 KB · Views: 9
  • test7.jpg
    111.7 KB · Views: 9
Last edited:
Last test today at 725 yards, I planned to do 600 yards, but chose a spot in the middle of the field, and ranged at 725 yards to the berm and i was like, oh heck, I'll just do that from here. I adjusted the fps on the Kestrel from 2825 fps which was 30 grains for the Berger Hybrids I had used before, and changed it to 2730 fps for the Vapor Trails using 28.2 grains, calibrated the weather values on the Kestrel, dialed the elevation and windage on the ATACR, sent a couple downrange, but no hits on the plate, left me scratching my head and the two shots was hitting to the right of the plate, just off the edge and a little low, I had just figured out why and it was that I forgot to adjust the BC values for the Vapor Trails on the Kestrel o_O and I was using the Berger Hybrid values, so corrected that and redialed elevation and windage again, sent a round and it contacted, and sent 3 more, each one contacted. Cluster of hits, probably measured 1.7 MOA at 725 yards roughly. Nice and consistent group using virgin Lapua brass. I'm going to fireform those brass in next month's 600 yard match. Repainted the plate and followed up with the 6.5 Creed and the .308 that I haven't used in a while. Overall they also averaged about 2 inches for the Creed using 147 ELDM and 3 inches for the .308 using Lapua 175 Scenars. Was a good day to kill the boredom.


  • plate1.jpg
    178.7 KB · Views: 8
  • plate2.JPG
    129.7 KB · Views: 8
VT are a good bullet.
I would find the one your barrel liked the most between the 105 hybrid and the VT, and compete with said bullet.
Smart call on using your fireforming load for comps!