Help With 300RUM

Discussion in 'Reloading' started by Winkfish, Aug 7, 2017.

  1. Winkfish

    Winkfish Member

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    I got a question for you guys that reload the 300 RUM.

    I just picked up a Rem 700 long range, so I figured that I would try and work up a load for it. My results were quite poor and I am wondering what your thoughts maybe.

    -The rifle was brand new. I shot 10 rounds through the barrel before I started. I don't know if that is part of my problem. Is the barrel too new and has not settled down yet, and therefor driving accuracy issues?

    There were 3 shots at each charge weight:

    I started here: New Nosler Brass, Retumbo, Hornady EDL-X in 178gr.
    The grouping was poor at best. The only semi reasonable one was the 94gr load.
    [​IMG]
    I cleaned the barrel with Hoppess #9, patch cleaned, and then fired 5 rounds before moving on.

    The next load was: New Nosler Brass, Retumbo, Nosler Accubond LR 190gr.
    [​IMG]
    The Accubonds were better than the Hornady. It looks like 91.5gr is ok.

    I have not had a load development set where they have had such poor groups in general. I am wondering where I should take this. Different charges, different bullets? I have 8lb of Retumbo so I would like to stay with that if reasonable.

    Thank you for your input.
     
  2. eshorebwhntr

    eshorebwhntr Well-Known Member

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    If it is a bone stock factory rifle the 91.5gr 190 LRAB combo is better than "ok" in my book. It looks like around .5moa or so. It may be that the best accuracy is with the bullets seated a little closer to the lands.

    I've loaded for a friends 700 LR in 300 RUM and it shoots really well but it's a single shot. Retumbo should be a good choice and get good results. I've only used H1000 to date but have had good luck with it.
     

  3. Barrelnut

    Barrelnut Well-Known Member

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    I agree with 91.5. I would at least revisit it and maybe try some seating dept adjustments with it before trying other bullets, etc.
     
  4. Dosh

    Dosh Well-Known Member

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    IMG_0650.JPG Wink, best load we found for my friend's 300RUM was Retumbo and the Berger 215 hybrid in his Montana rifle. Mag length, Nosler brass and 215M primer. This is the load Broz made popular. .35" at 200 yds. H1000 shot almost as well. Was very easy to find an accurate load for this bullet. I'm shooting them in my 30/378 also.
     
    Last edited: Aug 7, 2017
  5. rcol317

    rcol317 Well-Known Member

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    I shoot a custom built 300 Rum, found that Retumbo works great with Berger 210 VLD's but not as accurate with 180gr Nosler Accubonds. I use H-1000 with 168's and 180's for best accuracy and Retumbo for 210 VLD's. Found the same to be true with my 7mm Rem. Mag. 180's Retumbo, 168 and 140's H1000
     
  6. Winkfish

    Winkfish Member

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    Thank you for all the information. I will try an load up some additional 190 Accubonds at the 91.5 and I will have to get some Berger rounds on order. It may be a week or two before I can get it out again to test and I will give you all an update.
    Thanks again.
     
  7. AZShooter

    AZShooter Well-Known Member

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    Before you continue your load testing, I suggest you use other cleaning agents besides Hoppe's #9. You don't mention any other cleaner so if I am mentioning other cleaners that you already use forgive the following: You are going to have a copper buildup that won't be addressed with #9. Readily found Barnes CR-10 or Sweets 7.62 will work but don't let either cleaner sit in the bore for very long. Continue to push wet patches through bore till all traces of blue are gone. Neutralize either ammonia based cleaners with #9 followed by some dry patches. (I use CRC brake clean in green can to remove all traces of ammonia, same as what Tye at Barnes uses) My personal favorite cleaner, which is usually purchased on line, is bore tech eliminator. Eliminator can be left in the bore for extended soaks to remove the fouling that RUM will create.

    Also before you continue your load testing be certain the rifle is sound.
    There are quite a few things that should be addressed:

    Most rifles respond to being bedded with most or all of the barrel floated. If there is a front pressure point in the stock remove it.

    Check front action screw hole for bedding material or possible bottoming out (not all actions have a blind hole)

    leupold windage style base windage screws not tight

    Front scope base screw touching threads of barrel..

    imperfection in crown

    action screw hole in stock too small, drill larger so sides of action screw won't touch

    Bolt handle touching stock

    Mag box must not bind in stock

    Recoil lug making early contact in bottom of bedded slot
    causing the action to sit off bedding

    Front of trigger group must not touch stock

    Trigger guard must not touch trigger

    Uneven bedding--- tightening one action screw to see if the action pulls up at other end.

    I know having to deal with all these possible issues can be frustrating but that is the difference between a custom and a factory rifle, we have to sort out the minor flaws to ensure it will shoot.

    I look forward to hearing how your rifle responds to your load testing.
     
    RockyMtnMT likes this.
  8. RockyMtnMT

    RockyMtnMT Official LRH Sponsor

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    ^^^^This is very good advice.

    I would spend time doing a barrel break in until the copper fouling stops. Shoot clean 1 shot at a time until the copper fouling stops. Then 3-5 shots clean until copper stops. This could take quite a few shots. Factory barrels are notoriously bad for copper fouling.

    We picked up 5 of the Remington long range rifles that we will be doing everything on the list that AZ provided and then turning around and selling them. Plus we will be adding muzzle brakes to them and aftermarket triggers.

    Good luck. I think the long range rifle is the best buy out there, they just need a little love to get them in line.

    Steve
     
  9. Wedgy

    Wedgy Well-Known Member

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    And feed them the right bullets !
     
    RockyMtnMT likes this.
  10. Buckskinner

    Buckskinner Well-Known Member

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    You can up your powder loads quite a bit, which might help as well. Mine likes 200 AB's and use Rem 9 1/2M and 95 gr of Retumbo.
     
  11. Ksmirk

    Ksmirk Well-Known Member

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    I'm new to the big 30's so take it for what it's worth but I've read several things that mention to not use Retumbo on the 180 class bullets or lighter, I'm working up loads now in my 300wm with Retumbo with the 215 Berger and besides some odd velocity numbers or at least I feel they are odd the groups have been ok and seem to be getting better. Later,

    Kirk
     
  12. Wedgy

    Wedgy Well-Known Member

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    If you are using magazine length you will find that some bullets do not like that far of a jump. Try using the Hammer Bullets or the Berger hybrid type or as they are not sosensitive to seating depth.
     
  13. Triple BB

    Triple BB Well-Known Member

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    My favorite gun is a stock factory Rem 700 300 RUM. I shoot Retumbo with Nosler 180 grn accubonds. The only thing I did was bed the action and have the trigger adjusted down to 3 lbs. This was last fall. 180 Grn Accubonds.JPG
     
  14. Lefty7mmstw

    Lefty7mmstw Well-Known Member

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    both of my 300 rum rifles act like that with the 200gr eld-x. I frankly think the eld-x is not really up to the task of getting launched from the bigger rifles (my 7stw also sucks with the 1275 eld-x, even though she is a 8" twist and should be fine). try 180-200gr accubonds or go with the 225 hornady or 230 berger; whichever suits you. I shoot the 180 hdy flat base or 225 hdy hpbt in my 300 rum rifles, but they also shoot the 200 sierra bt decently.