7mm rum 7mm rm 180 vld velocities

Discussion in 'Long Range Hunting & Shooting' started by linksmechanic, Nov 19, 2009.

  1. linksmechanic

    linksmechanic Well-Known Member

    Messages:
    668
    Joined:
    Jan 16, 2007
    Guys with these calibers what are you getting in velocity with the berger 180 vld and 168 vld? I just picked up a 7 rum sendero 2 and am wondering what to expect compared to the 7rm. I was getting an honest 3000 fps with the 180 with no pressure signs. Fast barrel maybe? Also it seems hodgdon's data seems to be very conservative. Does this sound right to you guys? I remember the first can of retumbo I bought(around 4 years ago?) at 68 grains the velocity was near 2900 on the bottle and now it's 2800. My chrono(ced m2) is giving me right at the 3000 range. I have a very, very faint ejector mark in the middle of the summer. Thanks for any input.
     
  2. liltank

    liltank Well-Known Member

    Messages:
    4,158
    Joined:
    Nov 3, 2008
    I can speak for the powder load part. Most if not all manuals are going to be conservative. The reason being is the lawyer setting at the desk at the company telling everyone it has to be safe. To many different rifles hand max loads at different pressures. So they post a max load that should be with in the original design of the pressures listed by the creator of the caliber. Hope this helps with the load info. I generally put loads together that are 1 to 1.5 grains over max without any problems.

    I like your numbers for the 180's out of the Rem Mag. That is encouraging.

    Tank
     

  3. linksmechanic

    linksmechanic Well-Known Member

    Messages:
    668
    Joined:
    Jan 16, 2007
    Anybody else?
     
  4. montana_native

    montana_native Well-Known Member

    Messages:
    565
    Joined:
    Oct 4, 2008
    I was barely breaking the 2800 fps mark with 180's out of my 7 RM. That was with Lapua brass and Retumbo out of a 26" barrel. Primers would start getting pretty flat at about 2825 fps.
     
    Last edited: Nov 22, 2009
  5. Limbic

    Limbic Well-Known Member

    Messages:
    320
    Joined:
    Jun 26, 2008
    I've shot 400-500 of the 168's and 180's combined from a 7mm RemMag with a 26" shilen barrel. 1:9 twist. I shoot in warm weather at 250 feet above sea level. Roughly.

    I found that the accuracy for the 168's was best at about 3000 fps. I was using 64g of RL22 I believe. .080 off the lands! Routine 1/2MOA. I could push it faster but accuracy dropped off. Because of this I switched to 180's. .01 off the lands. Near max load of Retumbo (68g) gives me 2950 fps with the same 1/2MOA accuracy out to 300 yards (shooting range max).

    I've run the numbers through my ballistic calculator and at 300 yards this load hits about like a factory 300 win mag with 200g accubonds.

    More than one person has commented that 3000 fps is the magic # for the 7mm VLD.

    BTW where do you get 7mm Laupa brass?
     
  6. linksmechanic

    linksmechanic Well-Known Member

    Messages:
    668
    Joined:
    Jan 16, 2007
    Lapua doesn't make 7rm brass. I think maybe he is thinking norma?
     
  7. montana_native

    montana_native Well-Known Member

    Messages:
    565
    Joined:
    Oct 4, 2008
    No, it's Lapua brass. There was a guy on Gunbroker selling it a while back. He had 250 pieces of it, I bought 150 of it.
     
  8. linksmechanic

    linksmechanic Well-Known Member

    Messages:
    668
    Joined:
    Jan 16, 2007
    That's interesting. Is it stamped "7 remington magnum"?
     
  9. BIG MO

    BIG MO Well-Known Member

    Messages:
    142
    Joined:
    Jul 20, 2009
    I'm running 66.8grns RL22 in 7mmRM with norma brass, 180 berger, .120 from lands. My crono is reading 3000fps and its printing submoa @1000yds. I went through a box of bullets before finding the sweet spot .120 from the lands. I could not run this much powder with the bullets seated closer to the lands without amping up the pressure.

    This is the third time I have loaded this batch of brass. I have only neck sized the brass and they still chamber with just a slight bit of press and the primer pockets are still tight as a drum. Primers show a little crater and no extractor marks on the brass. I did fire lapp the bore with the tubbs before load development.

    I feel this is close to max in this rifle and no reason to push it further. I shot a big Mo buck in the shoulder with this load last week @ 150yds. It was a big bang flop DRT.
     
  10. linksmechanic

    linksmechanic Well-Known Member

    Messages:
    668
    Joined:
    Jan 16, 2007
    Thanks for the info. I was wondering if I was the only one obtaining these kind of velocities with this combo. My load is super accurate. I really want to know how far people are pushing the 7rum with this bullet. On your seating depth did you mean .012"? Just curious.
     
  11. Coyboy

    Coyboy Well-Known Member

    Messages:
    2,132
    Joined:
    Jan 30, 2005
    My 7rum is pushing 180 bergers around 3250 fps with retumbo. Brux barrel 27"
     
  12. linksmechanic

    linksmechanic Well-Known Member

    Messages:
    668
    Joined:
    Jan 16, 2007
    Is this a "hot" load cowboy? Are you seated at or in the lands? Thanks. Oh and what powder? I have retumbo but was thinking us869
     
  13. Coyboy

    Coyboy Well-Known Member

    Messages:
    2,132
    Joined:
    Jan 30, 2005
    Off the lands, don't remember how much. Not a hot load it is with-in book max, may-be 1-2 grains under. 869 gave higher velocities than that within book max.
    My cronograph reads it at 3225, but balistic calcs compared to actual drops says it's at 3260.
     
  14. linksmechanic

    linksmechanic Well-Known Member

    Messages:
    668
    Joined:
    Jan 16, 2007
    That's funny you mention your ballistic program #'s have to be fudged higher. This is the same experience i have had with my 7rm with bergers. I thought it was nuts when they lowered there b.c. because I have found the opposite. I'm a little bummed with the 7rum I just got because it has the most freebore I have ever seen. My sendero 2 in 7rm is perfect. The bullet enters the case plenty and I am free to seat to the lands if I want. Not so with this gun. I can't even get to the lands. Way too much freebore. My experience with the bergers in many calibers is that they like the lands and I guess I'll see if they work way off the lands.