Point Blank Range sight in

Discussion in 'Long Range Hunting & Shooting' started by rufous, May 23, 2011.

  1. rufous

    rufous Well-Known Member

    Messages:
    174
    Joined:
    Jul 17, 2001
    In the past I have always zeroed my big game rifles at either 250 yards (for my 300 Win Mag) or 275 yards (for my 7mm Rem Mag) in order to have the bullet no higher than 3” at its highest point which comes at about 150 yards. I am considering zeroing my 300 Win Mag for 300 yards but am wondering if I might mess up and wound an animal by hitting too high at mid ranges.

    I have over 20 years of big game hunting experience and have taken deer at 450 yards and 508 yards, black bear at 530 and 540 yards (as well as many deer and bear at closer ranges) along with 2 mountain lions at 330 yards and 400 yards so I am not blowing smoke when I say that I am good with my rifles in the field. No doubt there are many here who are much better than me but I am no newby to this longer range hunting.

    I am likely going to switch loads in my 300 Win Mag. I have been using the Barnes 180 TSX at about 3000 fps but I think I will switch to the Barnes 200 LRX. I am getting an average of 2985 from my 25” Broughton 5C barrel using the F215 primer, WW case and Ramshot Magnum powder. I have a Leupold VX3 3.5-10 reticle with their Boone and Crockett reticle. Assuming the ballistic coefficient is truly 0.546 as Barnes claims and elevation is 3000 feet if I zero this 200 grain LRX load at 300 yards my bullets trajectory would be within 1” of point of aim at 400, 500, 550 and 600 yards using the B&C reticle's additional aiming points.

    So far I have only fired one group at 500 yards with this new 200 grain load. I got a 3.65” 3 shot group in breezy conditions. My old 180 TSX load was similarly accurate. I decided to try the 200 LRX partly for the fun of it and partly to reduce wind drift at longer ranges.

    If I zero this new load at 250 yards the bullet will hit 3” higher than point of aim at 550 yards (42” of drop instead of 45” that the reticle expects). I know that is not a huge difference and that if I think about it I could aim 3” low at 550 in order to account for that but I wonder if I would be better off zeroing at 300 yards. What do you all think? Thanks, Rufous.
     
  2. silvertip-co

    silvertip-co Well-Known Member

    Messages:
    1,131
    Joined:
    Jun 20, 2007
    Just zero it for 300yrds if you are west of the Big Muddy. That 'point blank range' stuff is a lot of hooey.
     

  3. J E Custom

    J E Custom Well-Known Member

    Messages:
    7,309
    Joined:
    Jul 29, 2004

    I would recommend sighting in at 200 yards and having a drop chart for 300,400,500,ETC.

    I use a small piece of paper on top of the scope ocular lens with the drop chart printed on it
    covered with cellophane tape for protection.

    Longer zeros present problems at close ranges and at longer distance time is not as important
    to acquire targets.

    Point blank ranges are OK for chest shots but not very precise. If someone wants to use this
    system I recommend 5" total PBR, 2.5" high and 2.5" low.

    Shots over 300 yards should be milled or ranged for best results .

    Just my opinion.

    J E CUSTOM
     
  4. fj40mojo

    fj40mojo Well-Known Member

    Messages:
    392
    Joined:
    Jul 25, 2009
    I use MaximumPoint Blank Range to calculate zero for all of my rifles and use the same ballistics calculator to generate drop charts for them too for ranges beyond MPBR. You have to go to the field and prove that your zero is correct and test your drop charts too, but you should be doing that if you are dialing dope into your scope too. Fact of the matter is that the majority of shots on game are within 350yds unless you are specifically looking for a long range shot, and for most modern cartridges MPBR for a 8" tall vital zone (elk and deer) is right there around 350yds. By using MPBR you simplify the process of harvesting game at most common ranges to just hold on the vitals and squeeze. I know many who read this will scoff at what I say, most probably don't think I belong here, but you don't always have time to range the animal, dial in your dope and get an ethical shot off, so why not simplify the process for the ranges where the majority of those shots are going to come. Longrange is how I increase the number of opportunities I have to fill my freezer, not the end goal. Smart, logical, practical-Hardly "hooey". Oh, and I've hunted my entire life west of the Big Muddy.