I need to push a 180g 30cal over 4000fps what are my options

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by ICANHITHIMMAN, Jul 6, 2010.

  1. ICANHITHIMMAN

    ICANHITHIMMAN Well-Known Member

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    Hay guys this question is for my father in law he got me in to this and he is a speed whore! Right now he is pushing some 115 BARNS 30 cal bullets at 3500+ out of his 300 RUM its his thing he likes to go fast.

    He wants a 30 Cal that will push 180g at close to 4000 FPS I did not have any advice for him. I said 30-378 but I know it will not go that fast.

    He wants to go fast so I need sugestions???


    Jon
     
  2. Camshaft

    Camshaft Well-Known Member

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    Its probably going to take some kind of. 308/408ct hybrid. Kirby can probably build it of get you headed in the right direction
     

  3. Broz

    Broz Well-Known Member

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    I have pushed a 168 gr over 3700 in a 30-378. But the brass life was short.

    This is something Longtimelongranger can help you with I bet.

    Jeff
     
  4. ICANHITHIMMAN

    ICANHITHIMMAN Well-Known Member

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    Thanks alot guys Im hoping Kirby Will chime in or anyone for that matter who can give me help. He works 24/7 and has been out of the loop for some time.
     
  5. Broz

    Broz Well-Known Member

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    Thats good!! Because if he had very much time to shoot he would go broke buying barrels for this thing...:D


    Jeff
     
  6. ICANHITHIMMAN

    ICANHITHIMMAN Well-Known Member

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    Another veary good point and Im trying to talk some sense into him but I haven got there yet he is stuck on speed I dont get it but oh well he has money to burn I guess.
     
  7. phorwath

    phorwath Well-Known Member

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    I've never read of muzzle velocities reported near 4000 fps with a 180 gr .308 bullet. Of all the members of this Forum, Kirby comes to mind as the best source for the lowdown on such an ambition. I'd send him a PM.

    To my knowledge, Kirby never marketed a .300 Allen Magnum. He jumped from his 7mm Allen Mag up to the 338 Allen Mag. IIRC, he wasn't able to design or conceive of a practical 300 Allen Mag that substantially improved upon the 300 RUM.

    My guess is that 4000 fps with a 180gr .308 will not become a reality with any shoulder-fired weapon that's practical for hunting, at least with the use of brass casings. The college effort might involve the use of casings with screw on steel case heads that allow much higher pressures to be employed without blowing gases out around the primer pocket. The first point of failure would likely then be from the equivalent of a pierced primer. I knew of a guy about 20 yrs ago that was having steel case heads custom built for his .338-.378 Wthby Magnum. He was able to run the case pressures substantially higher than with brass casings. The overall casing length was increased from the standard brass casing, and each custom manufactured casing was very expensive. He had to have a custom reamer built for the elongated cartridge case. The steel case head more or less screwed onto the meaty portion of the .378 Weatherby case heads. This guy was a doctor with plenty of money to burn. I don't know the details on the velocities he was getting. My information was 2nd hand from my brother who's a local gunsmith and gunshop owner. I think the effort was rather short lived, because I only heard about these steel case heads for about a 1-2 year time period. There were probably some safety and cost-effectiveness issues that brought the experimentation to an end.

    At the elevated pressures, barrel life would likely be significantly reduced.
     
  8. bassin93

    bassin93 Well-Known Member

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    I ran 168 grn barnes tsx at 3730 out of my sendero 300rum with 105 grns of retumbo. shot 75 of these before I smartened up. Went to the 208 Amax at 3150. Now with only 450 rounds down the tube it is trashed. I bought it to build an edge anyway so I really didn't care about the barrel at first, but, it shot so damn good I wished I wouldn't have done it. Brass only lasted two loadings before the primer was too loose to stay in.
     
  9. Varminator 911

    Varminator 911 Well-Known Member

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    You're going to need a 36-48 inch barrel and probably 140+ grains of powder. Even with the highest BC bullet it still won't equal an Edge with 90 grains powder and a 300 SMK past 1000 yds for energy or wind drift. It will be way behind in smack down power.

    But out to 500 yds it would be a blast.
     
  10. Camshaft

    Camshaft Well-Known Member

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    I'm guessing that if you started with a .30.378 and ai'd the shoulder and ran a 34"+ barrel you might get some very impressive speeds. And drop to a 170gr solid. You might come close.
     
  11. BountyHunter

    BountyHunter Writers Guild

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    RPMs will tear jacketed bullets apart unless you go to a 1-15 or higher twist I would bet also.

    Figure 400-600 rounds for barrel life, but other than that sounds reasonable:D

    BH
     
  12. MachV

    MachV Well-Known Member

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    I've pushed the 250 grain Barns bullets to 4350fps but that was by necking the 50BMG down to 375....Never did hit anything with it though as accuracy was poor!! Like others have said it could be done but finding a 180 grain bullet that will take the RRRs is gonna be tuff,barrel life is gonna be extreemely short and accuracy will be very challengeing.
    Have had some luck getting the 55 Nosler past 4k out of the 243 and the little 39 grain Sierras fly great out of the little 20PPC past 4000fps but a 180 30 cal???
     
  13. ICANHITHIMMAN

    ICANHITHIMMAN Well-Known Member

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    great guys thanks i will pass on the info i enjoyed all the responses and I agree with all of you. I just have no practical experience with this I like heavy bullets at a safe speed.
     
  14. RockyMtnMT

    RockyMtnMT Official LRH Sponsor

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    If he runs the 177g GS HV bullets out of his RUM he can get to 3500fps. I am running them out of my 30-338 Lap imp @ 3660fps. That is with a 30" barrel. As far as I know he is not going to get much faster than that.

    At .638 bc this will out run the big heavy bullets out past any practical distance for drop and drift.

    He will need at least a 10 twist to run this bullet. If he is planning on hunting past 500 yrds 10 twist is just right. If he is hunting under 500 yrds then he would be better served with a 9 twist. This has to do with the bullet tumbling on impact. I have not experienced the bullet tumbling on shorter shots but they say it could happen with out the faster twist. I think that the RUM will run them fast enough with a 10 twist to work at any distance.

    4000 fps is fun to think about, but I don't think he is going to make it with out going to smaller calibers. GS Custom built a 22-06 Easling that they are running @ 4700 fps. They hunt Afican game out to 400 yards or so with it, and claim good barrel life using the HV bullets.

    My .02, Steve