This is a great thread! Especially since I got a new 7RM Sendero and am working up loads. I shoot 1000yd IBS matches with 7mmSTW and 6.5x284's but wanted a "tactical gun", I love the Sendero. I put on a Jewell trigger and a VAIS muzzle brake (it took the sharp kick out and sends the sound toward the target (I had a Browning A-Bolt with BOSS, the BOSS sent the sound sideways and sounded like a fifty)) Both additions highly recommended.
So far, after several rounds of testing, I have found the following...
Today at the range (2/25/09) Incremental Test of 15 rounds 68.0 to 70.8gr H1000, GM210M with JLK 168 .020" into lands = Groupsize = Scattergun
Got most consistent velocities with Sierra MK 168's, AR-25 (67.0gr) GM215M seated .020" off of the lands. (1 MOA)
I noticed that if I moly the inside of the necks with the NECO Case Neck Lubrication setup (BB's in a little jar smothered in moly dust, stick case neck into BB's and a little graphite gets inside the neck)) I get much less velocity spread and better bullet release (.002" neck tension)
I tried 72 gr. Retumbo but velocity was all over the place with 5 different types of primers (GM210M, GM215M, WLRM, CCI, ???).
I'm still sifting thru this thread and have found several good loads to try. According to my Bullet Stability Calc, the Berger 180's are unstable in our 1 in 9.5 twist barrels yet some on this thread are having success with them.?? I have a few Bergers laying around.... I'll try it..
So, so far no loads that are consistent and repeatable. I'm certain I can get under a 1/2" MOA. I'm going to try some Berger 180's, Sierra 1975's, and also try to shoot these VLD bullets off of the lands (which is not what VLD's typically like) It's off to the range....