.300 RUM loads, pressure signs?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by 300 Rem, Sep 27, 2008.

  1. 300 Rem

    300 Rem Member

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    Sep 23, 2008
    Shooting Rem 700 SS .300 RUM, 26" barrel and I'm interested in other shooters' favorite loads. I've read about quite a few and it seems I'm using a fairly mild load (92.5gr Reloder 25, 180 gr Swift Scirocco, 3100 fps). Even with this load I get slight ejector marks on the case head (small circular imprint), which on some cases is hard to distinguish. Is this sign alone reason to be concerned? I've probably shot 100 rounds of this load, and it shoots well.

    I'm trying to work up a load using 180 Nosler Accubonds and thinking about giving Retumbo a try. I tried several "mild" loads using this projectile and IMR 4350 (80 and 81 gr) and also the same 92.5 gr RL-25. All of these case heads show the same faint ejector mark as my Scirocco load. I haven't had any trouble shooting sub-MOA groups, just curious about the possible pressure signs. At these charges I'm already not reaping the true benefit of the .300 RUM, trajectory-wise.

    I guess the question is, are these marks common on most other shooters' loads? Or is this just my bad luck with my particular rifle? The cases I'm using are Rem, full-length resized, trimmed to 2.843", cleaned primer pocket, deburred flash hole, COL 3.603", using Fed 215 primers.

    Interested in favorite loads (with 180 gr) and other reloaders' experiences.

    Thanks in advance
     
  2. mrultramag

    mrultramag Well-Known Member

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    Jun 9, 2005
    Usually its no big feat to achieve 3300 fps MV out of stock mod 700 rem 26" bbl 300 rum. in my experience 94-96 gr RL25, Fed 215, most any jacketed lead 180 bullet--ab, partition, etc. not barnes all copper. OAL max to fit magazine-usually 3.650 or so. You may have a rather sharp edged ejector hole in your bolt. If you use a chrono, I would try edging the load up in small increments to increase velocity if you want keeping watch for other pressure signs as well. My experience with rem brass in the 300 rum is that when you are running too hot the primer pockets don't last long (primers seat loose after 1 or 2 firings). I don't run 180's anymore out of my 300. I like the 200 ab better at about 3150 using rl25. It seems to me that you are running a pretty darn mild load to be getting ejector plunger marks on your brass. My favorite load is 92 gr RL25, rem brass, fed 215M, 200 gr AB, OAL 3.650, 3150 fps ave @ 15 ft. My most accurate 180 gr load was 96 gr RL25, rem brass, Fed 215, 180 gr SST, Oal 3.650, 3380 fps. That 180 gr load was plenty warm. A lot of guys use retumbo in their 300 rum. I couldn't get the accuracy in my gun.
     
    Last edited: Sep 27, 2008

  3. dogdinger

    dogdinger Writers Guild

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    Dec 1, 2007
    my pet load is 95 grs of H-1000 w/180 gr AB....3250 fps in a stock 26"BBL. it shoots .5".....AJ
     
  4. 300 Rem

    300 Rem Member

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    Sep 23, 2008
    Thanks for the input. Based on my low velocities and mild charges, I am inclined to think my loads are not over-pressure, even with the ejector plunger marks. I've tested hotter loads and the cases always look the same, so maybe it is a sharp edge on the ejector. I'll head out to my range in tomorrow and test again.

    Thanks again.
     
  5. WYO300RUM

    WYO300RUM Member

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    Mar 23, 2011
    I know this is a reply to an old post but this weekend I shot some loads in my 300 RUM and thought I'd share. For a long time now I've been shooting a Barnes 180 gr. TSX and last two yrs the TTSX. I use 100.0 grs. Retumbo with eathe a Nosler or Federal case and Federal mag primer. I have gotten 1/4 to 3/8 in. centet to center 3 shot groups. The 4th shot always opens the group up on all my sporter weight barrels even when cooling between shots. I wanted to try some Federal Match mag primers to see and difference. Still shoot a 3/8 in grp. my 4 shots averaged 3419 fps out of 26 in. barrel with std. dev. of 18 fps. I've tried a lot of different bullets including Accubonds,Interbonds,Sciroccos,E-Tips,etc. and none have shot ass good as the Barnes TTSX and TSX . Wanting to try some Berger hunting VLD's. My 7mm Rem Mag loves Barnes TTSX w/69.0 grs. of RL22 for 3/8 in grps. and ave. 3303 fps. out of 24 in. barrel. Hope you get this and can try the load if you haven't already since this post is 3 yrs. old !
    Don:D