7mm/08 AI vs 7mm RUM

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Jason, Jun 21, 2007.

  1. Jason

    Jason Member

    Jul 20, 2001
    I know this may sound like an odd comparison but I have a 7mm/08 Ackley Improved. I shoot Berger 168 gr vld bullets at 2748 fps. I was doing some comparisons on the computer the other day with a 7mm RUM.
    Shooting the same bullet at 3175 fps the RUM is only 15% faster and with 30 % more energy and 20% less wind drift at 1000 yards than the 7mm/08 Improved. (Less drop too obviously)
    What I would like to know is would you notice that in the real world? You would have to shoot quite a few animals at long range with both calibres to get fair data would'nt you?
    What I'm getting at is you pay a big price in terms of recoil etc for not a huge gain in power, Would this gain be consistently noticable on deer sized game at say 600 yds or so. (1000 yds only for camparison)
    Taking the 1000 yds energy figures as an example the 7mm/08 AI has 922 foot pounds left at that range, the RUM has 1314. Would that kill when 922 fpe would not. Assuming everthing else was exactly the same. ( animal size , bullet placement etc )
  2. dbhostler

    dbhostler Well-Known Member

    Sep 12, 2002
    As I read your post, sounds like you've got your mind made up allready. However, if you can find a 7 RUM, take it hunting and then you'll know. At 600 both will be supersonic, but the RUM will get there faster and flatter. Nothing wrong with the 7-08, I've loaded and shot both.

  3. Hired Gun

    Hired Gun Well-Known Member

    Apr 21, 2003
    Elk come to mind.
  4. James Jones

    James Jones Well-Known Member

    Jul 1, 2002
    first off if I walk up to a bull elk with my 45 ACP and shoot him in the ribs point blank the bullet is going to kill him no doubt right? that less than 500 lbs of KE. Now if I shoot him with a 200gr Speer Gold Dot as opposed to a 230gr FMJ ball round he is still gonna die but the rapid expansion of the Gold Dot will cause more internal damage and he will most likely die a good bit faster.

    The same goes for rifle rounds I firmly believe that more stress should be put on the bullet performance on game and shot placement than shear power. I have seen more deer "knocked down" with a 243 than a 7mm Rem mag simply because the bullet in the 7mm was desgined to shoot big game like elk and moose so the bullet hit the small 125lb class deer and simple zipped through not expanding much but the deer shot with the 243 if not dropped in their track they diden't go very far because the bullets used expanded and caused massive internal damage.

    Now from what I have heard the 168gr 7mm Berger is a fast expanding bullet that does its job very well , and at 1000yds assuming that is does expand fast even at those velocites I would say that a deer would never know the differance , if anything the extra velocity of the RUM would make it penitrate less because it would expand faster so which one would kill better? , its a toss up.

    Like it was mentioned though the less time the bullet is in the air the less chance the wind has to move it around and the less critical your yardage guestimation and wind doping skills have to be.

    If I were a guid I much rather see a guy show up with a 7-08 that he shoot well cause hes not scared of it that a guy thats shooting the latest greatest super mag that he scared of
    the 7-08 will kill deer at 1000yds , it will kick less have longer barrel life cost less to shoot and help to improve your shooting skills and apperciate the LR shooting skills more than a super flat shooting magnum.
  5. Buffalobob

    Buffalobob Writers Guild

    Jun 12, 2001
    The difference between the 7-08 and the 7 RUM is that the 7Rum will be at its best with the 180 grain bullets and will be capable of breaking the heavy bones of an elk at 1000 yards.

    Put differently, the 7 Rum with the 200 grain bullet will deliver nearly 50% more killing power at 1000 yards than the 7-08 with the 168 grain bullet.
  6. kevinh1157

    kevinh1157 New Member

    Aug 19, 2009
    First of all, 30% increase in energy is hardly a small increase. That said, I don't beleive the deer will be able to tell the difference from the 7-08 AI and the 7 RUM. The difference will be in the ability to hit the deer. The 7 RUM is more forgiving in terms of small range errors in long distance. Further being said, I sold my 7 RUM and my 7-08 is my go to gun for deer hunting. The reduced recoil helps with concentration and making shot placement at whatever distance.
  7. azsugarbear

    azsugarbear Well-Known Member

    Sep 20, 2005
    Dead is dead, and the 7mm/08 AI will get the job done at most of the ranges we are talking about under normal conditions. I believe the reason most of us go to the big magnums is the greater margin for error they provide. The longer the shot, the more the shooting gremlins come in play. If I am off a little on my wind or ranging estimates, the magnum with the heavy vld bullet is more forgiving. If the only shot presented to me on a trophy elk is through the front shoulder of an elk quartering towards me at 800 yards, then again, I want all the weight and juice I can muster to punch through and down that animal quickly. In most hunting situations, either caliber will get the job done. But in tough situations, where I have worked long and hard to bring a shot opportunity together, I want to be able to bring as much power to the table as I can to ensure the highest chance for success. The price of this insurance is more recoil, and more throat erosion. It's the ante in the high stakes poker game that some of us prefer to play in.
  8. phorwath

    phorwath Well-Known Member

    Apr 4, 2005
    I can't be sure from your post if you're satisfied with deer at 600 yds or if you also plan to harvest deer at 1000 yds.

    At 600yds either cartridge will be fine. At 1000yds the 7mm RUM is the only choice, if limited to these two options. You won't be able to maintain bullet expansion velocity at 1000 yds with the 7mm/08 AI. For that reason, I wouldn't even consider using it at 1000yds for any large game animal. Varmints and targets - yeah.
  9. AlbertaAl

    AlbertaAl Well-Known Member

    Feb 11, 2008
    MY 308 loaded with 168 Berger VLD's averages 2735 fps
    The accuracy is phenomenal and consistent.
    Using compnonents like BERGER , Lapua brass and Varget with CCI BR-2 primers is my guarantee for top performance.

    So what's the 7mm-08 Ackly or Rum advantage, if any ?
  10. spinlite

    spinlite Member

    Nov 30, 2013
    I know this is a little off topic, but what is the performance differance between the 7mm-08 and the 7mm-08AI, and is the barrel life shorter on the AI?