Idea for Retumbo in 7mm SAUM. What do you think?

Discussion in 'Reloading' started by JARHEAD1371, Aug 30, 2009.

  1. JARHEAD1371

    JARHEAD1371 Well-Known Member

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    I'm trying to find a starting point for load development for my custom 7mm SAUM. Is a slow burning powder, like Retumbo, a good choice for 168gr Bergers and a 28" barrel? If not, what do you suggest? I was also considering RL-17, but it's faster burning. Any ideas?
     
  2. VTi

    VTi Well-Known Member

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    I spent a good deal of time experimenting with Retumbo in a longer bbl (28") 7wsm with the even heavier bullets - 180gr Berger VLD.

    I arrived at the conclusion that it did not work that well. It was consistent, but I could not push the velocity to the point I was looking for (3100fps +) and still maintain a COAL of 2.860" to easily feed out of AI mags. I got to about 3000fps, no pressure signs at all, but the powder was getting way to compressed for my liking so I didn't want to go any higher with the charges.

    Finally, I stepped down to H1000 and got fantastic results. I shoot several different 7wsm's and strongly believe H1000 is the single best propellant for the 7wsm and heavier bullets.

    Just my opinion, YMMV of course.
     
    Last edited: Aug 31, 2009
  3. Long Time Long Ranger

    Long Time Long Ranger Well-Known Member

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    I have never loaded for the 7 saum but my guess is way to slow for that cartridge. Try something faster.
     
  4. Coyboy

    Coyboy Well-Known Member

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    Ryan, I would think H4831sc and may-be H1000 would give good results.
     
  5. buckbrush

    buckbrush Well-Known Member

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    Another vote for H-1000. 168 Bergers, 2.850" OAL, 65 gr and getting 3065 fps.
     
  6. VTi

    VTi Well-Known Member

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    What's the barrel twist? If it's 1:9 or faster, just go straight to the 180 VLD's. I assume you're taking this rig well out past 1000yds, and the 180's ballistics are much superior at those distances.
     
  7. JARHEAD1371

    JARHEAD1371 Well-Known Member

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    It is a little faster than 1:9, something around 1:8.6 I believe. I was thinking about the 180's but I already had a new box of 168's. I plan on shooting at least out to a grand.
     
  8. saum7

    saum7 Member

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    Been thinking the same thing , I have loaded up some 180 berger's started with 65gr of AR2225 the same as retumbo , But not had the chance to fire them yet ,
    try looking at this site good write up about 7mm
    7mm Cartridge Guide .
    I think there is a person on this site goes by the name of Wild_Bill . Who is tring some loads with retumbo. Maybe he will see this post and reply.
    try looking here Big Stuff -- 6.5mm and Up -

    Cheers
     
  9. MontanaRifleman

    MontanaRifleman Well-Known Member

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    RL 17

    Out of a 24 3/8ths barrel

    3193 with 180 E-Tips seated to fit the mag

    2935 with 210 Bergers seated to the lands

    hard to beat that...

    -MR