Come on bullet makers!!!

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by load, Jan 29, 2011.

  1. load

    load Well-Known Member

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    I mean really! when the heck are bullet makers going to make a really good 30 cal projectile?
    Dont get me wrong the h 208 and b 210 are good and can shoot past a mile even in 300 wm however they do not bring out the full potential of the 30's! smks really are not a vld design and don't preform as such (still a good bullet) but what I/we as long range shooters really need is a secant ogive bullet like the burger 210 and hornady 208 with a bearing surface that makes jump easier to deal with! something in the 225 to 230 range would be premium! It should have just as high or slightly higher bc than the 240smk but still get better volocity!
    Enouph catering to the pansy little cals or the over bored big daddies and build one for the all American favorite the .308!!!!!:):cool:gun)
     
    Last edited: Jan 29, 2011
  2. groper

    groper Well-Known Member

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    The problem lies within the standard twist rate barrels in 30cal. Its not the projectile makes fault... The standard 1:10twist barrel would not be able to fully stabilize a 230gr VLD shape bullet. It would have to be very long in order to have a secant, large radius nose and 230grains in weight.

    And whilst your asking for something in .308win, how fast do you think you can safely push a 210gr bullet, let alone a 230gr???

    The 308win is already flat out pushing a 210gr @ 2600fps if your lucky... There is nothing more to be gained by going to a heavier bullet because what you gain in BC, you will loose in velocity and time of flight. This is no longer true for the big 30`s, as they have plenty of velocity already, they are simply lacking a bullet with a higher BC.

    Its the BIG 30cal cases that would benefit from a heavier VLD... but again, its only possible if people suddenly start buying faster twist barrels to shoot them... but why would you buy a faster twist barrel when you dont have the bullets available...? chicken or the egg, catch 22, conundrum...
     

  3. Moman

    Moman Well-Known Member

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    I've wondered the same thing and have looked for other options for my 300 RUM. I've ran data comparing the 200 AB (which I shoot now) against the 210 & 220 SMK as well as the 210 Berger and don't see a lot of difference.

    Now, check out Hornady's website. They are showing a new match bullet that will be available this spring. It is a 225 grain with a .670 BC. I know Sierra doesn't recommend a 9 twist until you get to the 240 so I would assume with proper velocity a 10 twist should stabilize this. I am looking into this new Hornady and trying to find any info on how well it would perform as a hunting bullet.
     
  4. JeffVN

    JeffVN Well-Known Member

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    No doubt 30 cal has been kicked to the curb when it comes to high BC projectiles, as compared to the 7mm and probably even the 6.5mm bullets.

    I know that a couple of the lathe turned manufacturers are producing solids that are designed to work in standard twist barrels, but the BC gain so far does not seem to be worth the price paid.

    But its still a good goal, standard twist, higher BC, nominal price.

    JeffVN
     
  5. James H

    James H Well-Known Member

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  6. load

    load Well-Known Member

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    I saw that earlier and its a good start. I like the expected 6.7 bc however its a copy of their 208 match bthp which is pushing lower bc's than than the 208 amax series.
    If they build one off their 208 amax it should show close to .7!
    i am excited to test out these new bullets when they do hit the market!
    when i ran theretical numbers based off of current 225 volocities the comparable volocities and bcs put the 225 and 208 nearly identical @1760 however if you take the difference from the 208 bthpm @ .62 (expected)and its brother at .67 (expected)you have .05 then add that to the .648 (advertised) of the 208 amax you'd .698 wich would give a good edge to that weight selection! the velocity/bc of this combo would also out perform the monster 240smk
    weres berger on this one?
     
    Last edited: Jan 29, 2011
  7. Michael Eichele

    Michael Eichele Well-Known Member

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    I maybe off base here but I am not sure how much more bullet weight the 308 can handle than the 208. You cannot get enough powder in a 308 to make anything heavier than a 208 have any significant velocity. At least not enough to make the higher BC worth while. If the 308/208 AMAX isnt enough for you then you should most likely be looking to another cartridge. The 308/208 combo is nothing to sneeze at as it is.

    My idea of a perfect 308 winnie bullet is 175-190 grains with a .6 to .625 BC that will expand on game as low as 1400 FPS and hold together on a shoulder shot at 2800 FPS. A 190 with a .625 BC would be about the best overall balanced bullet between speed and BC. Typically from a 26" barrel a 190 can be driven any where from 2600-2750+ with the right powder. Even at that, the 190 with a .625 BC would only have a very small benefit in wind and energy over the 208. The real difference here would be a combo near that of the 308/208 with a bit less recoil and a bullet that will hold together a bit better at close range.

    Kind of sounds like the 177 GS bullet except I cannot bring myself to believe that the published BC is any where near reality and I would need a new barrel to stabilize it. I would gladly get a new barrel if I thought the BC was close.

    M
     
  8. 3006savage

    3006savage Well-Known Member

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    I cannont understand why there is not a better selection of high BC heavy 30 cals out there either. It is the most popular caliber for big game hunting and there is certainly enough market for that niche.

    Take berger for example their heaviest 30 cal only requires a 1:11 twist while the vast majority of rifles are 1:10 twist. Why not at least make a projectile to take full advantage of the standard 30 cal twist rate.
     
  9. load

    load Well-Known Member

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    Stabalization depends on what gun your shooting it out of i.e. velocity. Take the .308 win and your probably right but the 240 grain smk WILL stabalize when shot out of a 300wm at 2650+ its all about rpm a vld design in the 225 to 230 range should stabalize in a 1/10 in any magnum rifle possibly even the good old .30/06. berger recomends a 1/11 fo their 210vld.
     
  10. groper

    groper Well-Known Member

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    Increasing velocity only has a very small effect on increasing gyroscopic stability. The primary factor effecting a bullets ability to be stabilized is its length.

    The berger 210vld would have a stability factor of around 1.4xx from the 11 twist barrel and you dont want to make it any less than this or you will run into stability problems when shooting in cold conditions at low altitudes. Bullet makers must have sufficient safety margin when quoting required twists for conditions like this.

    The new hornady 225gr bullet will be about as good as you will get from a 1:10twist barrel, and its only a small improvement from the 210grainers... if you want more BC than this in 30cal, you have no choice but to design a significantly longer bullet which means you have to goto a faster twist barrel.
    BC is not just gained purely from increasing mass alone, its only half the story. The rest of the equation comes from the drag of the bullet which is governed by its shape. Aerodynamically efficient shapes with low drag, are very long pointy shapes and due to their volume, a pointier bullet with a longer secant nose will be lighter for the same length. so in reducing aerodynamic drag your also reducing its weight for the same length and you end up chasing your tail with regard to BC... so you very quickly run out of room for improvement which is exactly what has happened in 30cal due to the common 1:10twist barrel.

    So designing a bullet for a significantly higher BC than whats already available in 30cal, just isnt feasable when your limited by a 1:10twist rate. Sure berger could design a slightly heavier bullet of 225-230grains and specify a 1:10 minimum... but dont expect the BC to be much better than their 210gr nad youll be running them a bit slower so youll loose most of what you gained anyway... go down to a 1:9 or 1:8 twist and then we can push the designs to much higher BC`s well above 0.7... same goes for alot of calibers tho... but whos gonna make bullets for barrels that dont exist, or are only able to be stabilized above 7000ft altitude and 60deg temps?
     
    Last edited: Jan 30, 2011
  11. elkaholic

    elkaholic Well-Known Member

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    This is EXACTLY why I started making my own! In the first place, making a super long range HUNTING bullet without a ballistic tip makes no sense. My 190's have a B.C. of .616 so I can start them a lot faster than the heavier bullets and because of the higher B.C., they have enough residual velocity at extended ranges to properly expand the bullet (which is a big problem with the high b.c. bullets presently being used). I can make the same bullet up to 260 grains with a B.C. that is off the charts but you would need an 8 twist and a huge case to get adequate velocity for long range expansion. Say a 30-378 8 twist. If someone wants to build one, I will supply the test bullets:D....Rich
     
  12. RockZ

    RockZ Well-Known Member

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    Rich,
    Don't temp us with that offer. I'm already building a new 7mm rifle!
     
  13. elkaholic

    elkaholic Well-Known Member

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    I'm dead serious! Build one and they will come!:D...rich
     
  14. Jon A

    Jon A Well-Known Member

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    I hope you don't mind, I'm holding you to that! RIGHT NOW!

    I am currently shooting a 1:8 twist 300 RUM:

    [​IMG]

    It will push 260's to the 2850 fps range easily. With a BC that beats the 300 SMK, that's plenty fast.

    I can test for BC, I can do penetration tests in gel.... Just make the damn things and send them my way!