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    • #30693
      DeadWoodDan
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      Been a while, haven’t had a productive year putting lead down range. Getting back to my “project” gun I last shot in June with jacketed rounds and was able to find a nice load quickly and reproduce same results every time. Now on to lead…I know there are alot of variables, but need to put some holes on paper to begin.

      Just need some guidance on what powder AND why to start with that I have on hand. From the searches I know there are those everyone else uses, but I either cannot find locally, haven’t looked hard enough or not at all. It seems the goal is slower burning powders? I know Larry had a thread recently with a similar build using H4831 and for what ever reason I just can’t find it here in the corn belt.

      Thanks to all that respond!

      Rifle: Sav. M12 BR, .308W, 1:12twist, 30″long tube

      Optics: VortexViper HS 6-24X50mm

      Boolit: 30XCB, Gator GC, sized .311″, Lube2500

      Powders On hand:
      RL15
      RL17
      H414
      IMR 4064
      H4895
      Varget

    • #30694
      lar45
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      I’ve been getting some good results with H4895 in my 30-06XCB with a 14twist barrel and velocities upto 2500fps.

    • #30695
      DeadWoodDan
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      Thanks Glenn. Them are the kind of holes I’m talking about…all touching.

      I am hoping my ignorance on powder selection will take a turn for the better over the next year.

    • #30706
      Larry Gibson
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      This may be some of the information you’re looking for?

      The 12″ twist rifle is a M70 Heavy Varmint rifle with a 26″ factory barrel on it. It has been pillar bedded and a rail put in the fore end for a hand stop. It is a very accurate rifle and shoots ½ moa with 175 MKs. I’ve “cleaned the 600 yard line several times with it and the 1000 yard line a couple. For testing it has a Redfield Ultimate 4×12 scope on it.

      With the M70 with 26″ barrel with 12″ twist I selected 3 powders that worked very well with the Lyman 311466 and LBT 30-160-SP; AA4350, H4831SC and RL22. I also decided on one load (a SWAG) with LeveRevolution powder based on it’s success in the 14″ twist Palma rifle. The attained velocities were about 50 fps less than expected across the board. The psi also never reached 40,000. Thus this bullet could be pushed a little harder in this 12″ twist rifle.

      The 43 gr load of AA4350 gave 2316 fps, 138,960 RPM at 32,200 psi(M43). The 1st shot out of the cold clean barrel went low out of the group as expected. The next 5 shots (2 – 6) went into .85″. The 9 shot group size was 1.15″The ES and SD indicated ignition and burn is borderline efficient.

      The 44 gr AA4350 load gave 2384 fps, 143,040 RPM at 34,100 psi(M43). The group size was 1.3″. The ES and SD was down to the expected norm.

      The 45 gr AA4350 load gave 2433 fps, 145,980 RPM at 35,700 psi(M43). The 1st five shots went into .63″ and the 10 shot group was 1.35″. The ES and SD were very good. I need to test this powder at 46 and 47 gr in this rifle. The Oehler M43 PBL for the 45 gr AA4350 load;

      The 43 gr H4831SC load gave 2159 fps, 129,540 RPM at 27,100 psi(M43). Nothing spectacular at 1.8″ group.

      The 45 gr H4831SC load gave 2289 fps, 137,340 RPM at 30,800 psi(M43). Another ho-hum group at 2″.

      Now the 47 gr H4831SC load was getting there at 2415 fps, 144,900 RPM and 34,500 psi(M43). The 1st five shots went into .7″ with the 10 shot group at 1.34″. The ES and SD were very good at 33 fps and 11 fps. This powder also needs to be tested at 48 and 49 gr in this M70 12″ twist rifle. The Oehler M43 PBL for the 47 gr H4831SC load;


      The 43 gr RL22 load gave 2153 fps, 129,180 RPM at 26,800 psi(M43). The 1st five shots went into .93″ with the 10 shot group at 1.7″

      The 45 gr RL22 load gave 2273 fps, 136,380 RPM at 30,200 psi(M43). The group was 1.4″

      The 47 gr RL22 load gave 2398 fps, 143,880 RPM at 34,100 psi(M43). The 1st five shots went into .55″ with the 10 shot group in 1.6″. This powder also needs to be tested at 48 and 49 gr in this rifle. The Oehler M43 PBL for the 47 gr RL22 load;

      The last test was just 1 load with LeveRevolution powder. I took a guess and figured 40 gr with a .3 gr Dacron filler should give around 2500 fps. I came pretty darn close! The 40 gr load gave 2510 fps, 150,600 RPM at 31,900 psi(M43). The 1st five shots went into .8″ with the 10 shot group at 1.5″. The ES and SD were outstanding at 21 fps and 7 fps.

      Larry Gibson

    • #30707
      Larry Gibson
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      Some other groups with H4831SC with the 30 XCB bullet in my M70 Target .308W w/12″ twist.

      Larry Gibson

    • #30708
      WCM
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      What year is your model 70 heavy varmint?
      I have one from the late 90’s with the factory barrel, and it is the most accurate rifle I own.
      I put a Jewell trigger on it, but other than that it is stock.

    • #30709
      Sgt. Mike
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      Dan you asked why here are some of my observations on the internal ballistics of why the results are so different with differing powders.

      I’m not talking external ballistics like the RPM th as some call it. Which effects the group size, rather I’m referring to launching the bullet within the chamber and bore as gently as possible.

      Kj/Kg and VMD values is one of the things that plays in powder selection as well as twist for stability and accuracy potential:

      Looking at what Larry recommends H4831 Kj/Kg is 3870, VMD is .0725 (H4831SSC is exactly the same just shorter kernels for meter ability)

      Glenn just showed a target with H4895 Kj/Kg is 4060, VMD is .0725 ok, notice that the density is the same the Kj/Kg is a little more but what is Kj/Kg??

      Well kJ/kG is described as
      a. Kilojoules per Kilogram
      b Heat of combustion
      c. specific kinetic energy

      Joule:

      It is equal to the energy transferred (or work done) to an object when a force of one newton acts on that object in the direction of its motion through a distance of one metre (1 newton metre or N·m).

      A netwon can be described as

      F = mâ‹…a = wâ‹…a/gF = mâ‹…a/gc = wâ‹…a/gF = mâ‹…a = wâ‹…a/g
      w = m⋅gw = m⋅g/gc ≙ mw = m⋅g
      ft/s2m/s2ft/s2m/s2ft/s2Galm/s2m/s2
      slughyllbmkglbgtkg
      lbkplbFkppdldynsnN
      lb/in2atPSIatmpdl/ft2BapzPa

      We know that kilo equals 1000

      For us the kJ part of the description is basically the amount of force and heat that occurs with 1 kG (=15432.4 grs)

      So what does 4080 Kg (H4895) mean for force in pounds force per foot 3,009,253.5 for each kG (194.9 pound of force per foot per grain) so x 38 grs should produce 7,409.8411783 pounds of force per foot.

      But I mentioned heat, well 4080 Kg equal 3,869.6 BTU (thermal).

      Kj value of 3870 (H4831/H4831SSC) = 2854365.5 pounds of force per foot divide by 15432.4 = 184.9 per grain x 38 = 7,028.452457323 pounds of force per foot. 3670.5 BTU (thermal)

      But let’s look at the case capacity

      VMD is Volume Measured Density in cc. This method of measure has served Lee very well with the Lee Loader system using certain bullet powder combinations.

      Looking at the two powders we see that both have the same exact VMD so using Glenn’s 38 grs X .0725 (VMD Value) = 2.755 cc
      Well what does that really mean? The 308 win case is at approx 56grs of H2O, the 7.62mm NATO case is 54 grs H2O but what is the cc of these cases?
      So take the 308 with the average of 56grs of water divide by 15.432 ( weight of 1 CC of water) =3.628cc so 38grs of H4895 or H4831 will be a 75.9% case fill for the average .308 Winchester case.

      For the 7.62mm NATO 54grs divide by 15.432= 3.499cc using the same weight of the powders 78.7% fill as this is a more confined area than the average 308 Win case the pressure drives higher.

      H414, Kj/Kg = 3880, VMD = .0661 use the same 38grs (2.5118 cc 69% fill)

      2861741.139979 divide by 15432.4 x 38grs = 7,046.6 pounds force per foot

      3679.9 BTU Thermal.

      Now there are factors that I have not covered that effects this even more. Actual chamber shape, leade length, configuration angle, throat diameter. Alloy, type of gas checks, lube properties, these are just a few.

      But really how does this affect us as shooters it will fall in the same category as the burn rate charts., Which is a guide to allow us to compare to, in order to find powders that will somewhat act the same if we can’t find exactly what we are looking for. What will drive what gives the best results one has to try, as the Kj/Kg value is the powder potential. The shape of the cartridge will determine the outcome (CUP / PSI that drives the velocity of the bullet as the confines of the chamber / bore increases the pressure).

      Bottom Line H4895, AA4350, H414 would be some of my prime choices for trying.

      Larry has shot probably more types of powders in the 308 win than most of us while having a Ohler shoot lab hooked up, his experience will out weigh what is listed on this page of theory based on newton’s law (my post). Larry’s method is a lot easier to understand and digest. What I have described explains bullet base damage, obturation, as well as barrel erosion theory.

    • #30710
      Sgt. Mike
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      The real take away is now you know how that kJ/kG value in Quickload relates to.
      Also just seen / noticed that Glenn posted data for a 30-06 which the case capacity is more that a 308 win. but the method to determine percent fill is the same regardless of case being used.

    • #30711
      Larry Gibson
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      WCM

      Mine is one of the early ones (mid ’70s?) With a Schneider barrel. It’s a very accurate rifle for sure but easy to duplicate these days.

      Larry Gibson

    • #30724
      WCM
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      Larry Gibson;n10583 wrote: WCM

      Mine is one of the early ones (mid ’70s?) With a Schneider barrel. It’s a very accurate rifle for sure but easy to duplicate these days.

      Larry Gibson

      Seems as though I remember my old State Trooper shooting buddy saying that they had an old Win Model 70 sniper rifle at the station that had a Schneider barrel.

      Thinking back I believe I bought my rifle in 93 or 94 . We instantly recognized that it had a great barrel on it.
      He bought one just like mine, but his was never as accurate as the rifle I have.

      My son has such great eyes,and he was recently getting just under 1/2 MOA at 200 yds with both the Sierra 168 and 175 MK bullets.

    • #30726
      Larry Gibson
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      I used to have eyes like that…..sadly I wasted them in my youth……

      Larry Gibson

    • #30727
      WCM
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      My biggest disappointment is I have no one to shoot with much anymore.

      I love shoot with my son, but he works so much he rarely has time .

      My old shooting buddy died, and there is no one much around here that likes to handload , cast and target shoot.

      So I shoot by myself most of the time.

      I really don’t need to buy any more guns. Just work with the ones I have with the time I have left.

    • #30743
      WCM
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      Thanks for posting you loads and results.

      Great information and test.

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