338 Rum load development

Discussion in 'Reloading' started by D.Camilleri, Jun 1, 2011.

  1. D.Camilleri

    D.Camilleri Well-Known Member

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    OK, playing with my rum again trying to find the perfect load. A little history, new broughton barrel two years ago 27 3/8, 1-9.3, #4 contour ,blueprinted action, sako extractor, , Muzzle Brake, Bell and carlson full aluminum bedded stock, canjar trigger, Sightron S III 8-32x56 worked up a quick load that worked and hunted with it. Load was 97 grains of RL 25 with a velocity of 3300 using federal cases with federal primers and 225 accubonds. Well, this was a great load until I started to reload some of the cases. Every other one had a loose primer pocket after only one firing. Well, with the cost of brass and the availability problem of brass, I decided to work up a different load.

    Went to the range a couple of weeks ago and loaded up some rounds with 100 grains of H 1000 and very suprised that I was getting over 3300 and some pressure signs. In the past with H-1000, I would be lucky to get 3100, so powder has gotten hotter.

    So, I loaded up some rounds with 99 grains of H 1000 and shot them over the new chono today. 225 barnes tipped tripple shocks shot about 3/4 inch @ 3300 and 225 accubonds shot about 5/8 @ 3250, not bad, but had a few more to try. 94 gr of RL 25 with 225 accubonds shot about 3/4 @ 3130, 95 gr of RL 25 had 3 shots in 3/8 with a flyer on 4th shot of about an inch @ 3200 and very low deviation.

    I also decided to try a load that another member was having good luck with, so I loaded a few with 86 grains of IMR 4350 with 225 accubonds and had 3 cutting same hole and 4th 3/8 off and hoovering around 3200. Very promising, but some ejector marks on the cases. Then I tried the same powder charge with some tipped tripple shocks and some definate pressure on the first shot and blew out a primer on the second shot around 3250, but definately high on the pressure.

    To keep all of this in context, I shot 3 federal factory rounds loaded with 225 accubonds, very low standard deviation, but lousy accuracy around 3 inches. I got home and pulled a bullet on the factory round and found 91 grains of some kind of powder, maybe h4831 sc, but not sure, doesn't match anything I have.

    I am temped to pull a few more of these factory rounds, neck size and reseat the bullets to magazine length the same as the rest of my reloads.

    Just throwing this info out there, the gun shoots well, probably a lot better than I do. I am leaning to the H 1000 load to get away from the temp sensitivity of the rl 25, since most of my hunting is when it is cold out.

    I have also done some testing with 225 hornady interbonds and the three of these bullets seem to be flying about the same @ 700 yards. It was a little too windy today to try and shoot any distance for load development, maybe tomorrow.

    Any comments?
     
    Last edited: Jun 1, 2011
  2. rscott5028

    rscott5028 Well-Known Member

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    I'm surprised nobody ever replied... I am completely unfamiliar with 338 anything. But, I'm thinking about building one. So, I was hoping to learn something.

    I see no point in altering factory loads. They're great to establish a baseline. But if you handload, you might as well build your ammo from the ground up.

    It also sounds like you've got a lot of variations going. Either you're shooting a lot or perhaps not spending enough time with one set of components?

    Are you using the Fed gm215m primers?

    How many rounds have you fired over 2 yrs? And, how's the barrel life?

    Might the throat be erroding forward? Do you need to check your COAL again and adjust your seating depth?

    In any case, 3/4" @ 100yds with a cannon like that will handle most people's hunting requirements. If it was me, I'd take one of the better loads and start fine tuning seating depth while paying close attention to brass prep. ..also, measure, weigh, and sort everything.

    Let us know how it turns out.
    -- richard
     

  3. GNERGY

    GNERGY Guest

    I started my testing with RL-25 and found out that every week it got hotter out so did my loads. I found out that testing at 300 yds instead of 100 was recommended by LRH members and it did work out better for me. Gives the bullet a chance to go to sleep and you might just get better results.
    Tarey
     
  4. royinidaho

    royinidaho Writers Guild

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    I don't understand why one would load hot a 225 grain bullet when a case full of 50 BMG and a 300 grain offering will out do it all the way around at LRH ranges? And cases last for more than several shots.

    Just my way of thinkin'. . .
     
  5. Topshot

    Topshot Well-Known Member

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    I would give the Hornady 225 grain Interbond bullet a try. They are very good on game. I use a load of 99gn H1000.
    Here is a photo of one pulled from a deer and an unfired one for comparison.

    [​IMG]
     
  6. JD338

    JD338 Well-Known Member

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    I have a M700 LSS 338 RUM factory stock except fpr the Pachmyer Decelerator recoil pad and a Mark 4 4.5-14 scope. Shooting the Nosler 250 gr AB with Retumbo.
    [​IMG]
    [​IMG]
    JD338
     
  7. rscott5028

    rscott5028 Well-Known Member

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    What twist does he have/need in order to stabilize the 300gr bullets?
     
  8. GNERGY

    GNERGY Guest

  9. royinidaho

    royinidaho Writers Guild

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    10 twist does just fine
     
  10. D.Camilleri

    D.Camilleri Well-Known Member

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    I got a chance to load some more and headed to the range today and shot only at 300. Nothing shot very well, with the exception of pulling some bullets from the factory federals, neck sizing and seating the bullets out to my max magazine length. These shot about 3 inches. I put both of my chonographs in line for the shots and found that there is about a 60 fps difference between my pro chrono and my new chrony, with the chrony reading faster.

    This barrel only has about 200 rounds down the pipe, and is a great barrel, but the new variable is the new stock. It is full length pillar bedded and I free floated the barrel, I checked it again today and I can slip a piece of paper down the length of the barrel channel. I didn't check the toque on the action screws yet, but I will.

    I didn't try any loads with 4350 today, just the h-1000 and rl 25. Velocitities were averaging between 3200 and 3250. I did clean my barrel before shooting today and it is soaking again now for the next set of tests. I am not really sure why the groups opened up so much going from 100 to 300 yards.

    I am not seating out as far as Tarey, because I want loads that will fit in my magazine.

    When I installed my new stock, all I did was relieve the barrel channel to remove any pressure, and torque the action screws. Is there anything else I should address as far as the bedding?

    After pulling bullets from the factory federal loads, I weighed the powder charge and they have 91 grains of powder, I wonder if the powder is h-4831sc, but I don't have any to compare too.

    My loads are all using cci 250 primers, some were with federal nickle brass and others were with remington brass, each set of loads was specific however. Kind of scratching my head right now, thinking I will make sure the barrel is very clean and then try some more loads with faster powder like Tarey did.
     
  11. D.Camilleri

    D.Camilleri Well-Known Member

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    Loaded some more rounds and shot today and I think I finally have a winner! 98 grains of H-1000 is giving me about 3220 ave, 1.25 group @ 300 and about 3 inches @ 500. I also had good luck today with factory federal ammo with 225 accubonds shooting almost the same as my handloads. Now for some drop charts.
     
  12. GNERGY

    GNERGY Guest

    That's good, I'm glad it's finally starting to be the laser it is designed to be.
    Tarey
     
  13. D.Camilleri

    D.Camilleri Well-Known Member

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    Tarey,

    My barrel seems to be producing the same velocity as yours, but mine didn't like the h*4831sc very well. I tried 91 and 92 grains and both were about a 4 inch group at 300 with 225 accubonds. 97 grains of h 1000 seems to be working well with the tipped tripple shocks. They seem to build a little more pressure than the accubonds and seem to settle in with a little less powder. I was hitting about 2 inches high at 300 and only dropping 15 inches at 500. 13 clicks had me hitting a bit low and 16 clicks had me hitting high and off the plywood. I had my target set in the top 20 inches of the plywood because the grass is so high due to all the rain we have had. I was really surprised how well the factory Federal loads shot with the 225 accubonds. I just placed an order for another 200 rounds (to good of a deal to pass up on, loaded ammo for the same price as brass)