FINALLY Got to Shoot My 338 Ultra Mag.

Discussion in 'Long Range Hunting & Shooting' started by GNERGY, Apr 14, 2010.

  1. GNERGY

    GNERGY Guest

    I finally got to shoot my new long range rifle.
    I had the Broughton barrel chambered and installed by Jim See @ Centershot Rifles. He also squared up the Rem. 700 action and lapped the lugs. He worked on the trigger and installed one of his 3 port Muscle brakes.
    NOW it kicks less than my Rem. .308 7400 semi auto.
    When I got the barreled action back from Jim, I opened up the scope mounting holes to 8-36 and modified the EGW 20 MOA base to take the larger machine screws. Then I opened up the bottom of the action to accept a longer magazine box. I also swapped out the factory recoil pad for a Decelerator pad.
    Then I bedded the Joel Russo and the factory HS Precision stocks.
    Here is that thread.
    http://www.longrangehunting.com/forums/f17/work-art-its-way-54165/
    I just got done sanding my JR stock with 400 grit and when it isn't so windy I will sprat it with auto clear ( will post pics when done )
    I then mounted a Burris Black Diamond 6X-24X-50 in some double signature rings.

    I plan on using the 250gr. NAB's so I started with 86grs of RL-25 and worked my way up in 1/2 grain increments, cleaning after every shot. That took a while and since I didn't get to the range till 1:00
    I am using Fed mag primers and my COAL was 3.800
    The first shot chrono'd at 2826 fps. ans the last round I got to shoot was 94.5 grains and it went 3153 fps. it was 6:00 and the range closed and they kicked me out, I told them I wasn't done yet :D But I had to leave anyway. The bolt handle was still easy to open.
    What are you guys loading behind 250 gr bullets?
    Here are a couple pics from the range.
    [​IMG]
    [​IMG]

    [​IMG]
    So I still have some more loads to shoot to find the one where the bolt handle gets a little hard to open and drop back 2 grains ( as per the Kirby Allen method of load development )
    I'll keep you posted, going back to the range on thursday gun)
    Thanks for looking and a big 2 thumbs up for Jims Muscle brake, makes it enjoyable to shoot.
    Tarey
     
  2. Long Time Long Ranger

    Long Time Long Ranger Well-Known Member

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    You are right in there where my rem 700 338 ultramag shoots. About 94 grains and 3150 fps is where I get my best accuracy/velocity ratio. With that you can flatten elk size critters at a half mile easily.
     

  3. GNERGY

    GNERGY Guest

    LTLR, thanks for the advice. So did you find that going any heavier started to show signs of high pressure? Flattened primers or hard to lift bolt.
    Tarey
     
  4. midwesthunter

    midwesthunter Well-Known Member

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    Very nice, I cant wait to get my RUM done.
     
  5. freebird63

    freebird63 Well-Known Member

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    Very nice. Not to sound too stupid here, but why the double scope rings?? is it because of the recoil or the size of the scope?? I know my gunsmith reccomended daul dovetail mounts on my 300RUM.
    Can't wait to here more details.
    Chuck
     
  6. bigbuck

    bigbuck Well-Known Member

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    Nice Rifle GNERGY. Youre going to love that Broughton ! If it breaks in like my 300 RUM did you will see some tight groups at around 80 Rounds Tim said around 100 but mine showed up at 80 . Then I moved out to 200 and had little Clover leaf groups :D.

    BigBuck
     
  7. Long Time Long Ranger

    Long Time Long Ranger Well-Known Member

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    I went back over my notes and 95.5 with re25 is the highest I went. Pressure signs started there with my rifle. 93-94 grains at 3100-3120 fps was where I hit my best loads. Mine is a standard 26" stainless remington barrel with brake.
     
  8. Oliveralan

    Oliveralan Well-Known Member

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    Very nice rifle! Looks exactly like my 308 set up actually. Same stock, rear bar, and my barrel contour is just a little heavier. Hope it shoots as good as it looks for ya!
     
  9. Moman

    Moman Well-Known Member

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    Tarey, that thing is bad a$$. I've followed your posts and all the work looks like it was well worth it. Very nice looking rifle. I'll look forward to reading your future posts on your progress and look forward to seeing some pics when you get the other stock on it. Good job.
     
  10. GNERGY

    GNERGY Guest

    Thanks guys for all the nice replys.
    Freebird63 Dual dovetail rings are single rings that twist in and not actually double rings. I used Signature Z rings and you could put as many as you have room for on the rail.
    I thought if 2 were good 4 would be better. I did some mule deer hunting here in AZ this past fall and after hiking in to different places, I found that I had to climb up some treacherous rocky areas, or backtrack a mile or so to get around them. So I figured if I were to ever fall with the rifle strapped on or carrying it, just MAYBE the scope would still be sighted in. I think the rings would be the weak link, if I didn't break the scope.
    Long Time Long Ranger, I loaded 20 rds. with 94grs. of RL 25 to go test on thursday.
    I cleaned it every shot for the first 10 shots and then shot it five times before cleaning it again. Now I have run 20 patches during the course of the day with bore tech eliminator and the patches still come out blueish green.
    How long does it take to come clean or am I over doing it?
    Bigbuck, how is your Broughton barrel to clean and what do you use?
    Thanks
    Tarey
     
  11. freebird63

    freebird63 Well-Known Member

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    All I know is its a sweet looking weapon and now I want one. I think I need to get my sendero 300RUM set up first before I consider a new project. good luck and keep us posted.
    Chuck
     
  12. GNERGY

    GNERGY Guest

    FIRST RANGE REPORT
    The first pic is the 15 shots I used to sight in at 100 yds. and find a load 2grs. less than max. I cleaned it between every shot for the first 10 and then after the next 5 rounds. LTLR said between 93 and 94 grains of RL 25 was accurate for him.
    So I loaded up 20 rounds with 94grs of RL 25 and Nosler 250gr. Accubonds
    3.800 OAL.
    [​IMG]
    The next 2 pics were the 250 NAB's that I shot at 200 yds they were all over the place. It was about 90 degrees out with some breeze and some mirage. I cleaned after every five shot string. They chroned at 3125 to 3160fps at 12 ft. from the muzzle.
    [​IMG]
    [​IMG]
    Any idea why they are all over the place, I let the barrel cool in between shots, at least 15 minutes.
    I thought maybe something was coming loose or the scope was taking a $$hit. So I cleaned the barrel and tried some 180 gr. Ballistic tips I loaded a while back that shot 3/4 inch at 100 yds. out of the factory barrel. I shot them over the chrono and they ran between 3558 to 3581 fps. laoded with 91gr. AA4350. So I know nothing is loose.
    [​IMG]
    So I know it will shoot. Should I try seating the bullets a litle farther from the lands, I am about .010 now.
    Thanks
     
  13. Chas1

    Chas1 Well-Known Member

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    Congratulations, nice looking rig and looks like a shooter as well. I too thought about going with 4 rings.
     
  14. Long Time Long Ranger

    Long Time Long Ranger Well-Known Member

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    Every rifle is different. It doesn't look like your rifle likes the 250's very much. I have a 338-378 that will not shoot the 250's but will shoot the 225's and 200's into 3" groups at 600 yards. The 250's shoot 4" groups at 100 yards. Back when the 338 ultramag first came out and I was testing it against the 338-300 ultramags the 93-94 grains worked well with the 250 grain sierra and it works well in mine now with the 250 accubond. Mine are seated to max length in the magazine which would be well off the lands and I can get them into 4" at 700 yards in a factory rem 700. I would shoot what shoots best and not try and force one bullet through it that it doesn't like. I also got some good loads with 7828 using the 250's. I would adjust the seating depth first and then adjust the charge and see if that helps. Your rifle just may not like the 250's. With that group all over the place another bullet may be the only answer.