Excuses for missing antelope

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by D.Camilleri, Oct 13, 2013.

  1. D.Camilleri

    D.Camilleri Well-Known Member

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    So I went 0 for 6 yesterday on antelope with my 300 rum with 215 bergers and I am not quite sure why. I just got back from the range and the first thing I did was verify my 100 yard zero. One inch low and two inches left. Hmmm. My shots yesterday ranged from 450 to 800 yards and two minutes left alone would account for every miss. Add in the minute low and that just made it worse. So at the range, I raised my turret one minute and reset the zero. I moved to the 500 yard target and elevation was good, but first two shots were 8 inches left. The wind was blowing about 10 mph, but I held up a piece of surveyers tape and the wind looked to be directly in my face. I moved the windage turret one and one half minutes right and now I was hitting 8 inches right of the bulls eye. So I moved back 3/4 of a minute and I was still hitting right. I moved the windage turret back to zero and was right on the money. What could cause this? Could the scope have gotten out of sync internally and then moving the windage put it back in sync? I also set up my chrono and checked velocities and I was reading 2956 +- single digits with the chrono set up at 10 feet.

    With the 300 back in the game, I decided to check my 338 rum, since it hasn't been out since my deer hunt last month and it took a beating from the weather. It printed two inches right at 100. So I moved my windage turret and rezeroed it and went to 500 and the elk are in trouble again. I also checked my barrel channel since I had my bi pod on to make sure I wasn't getting a pressure spot and it checked out good.
     
  2. ICANHITHIMMAN

    ICANHITHIMMAN Well-Known Member

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    WOW that stinks, what do you think it was? Wood stocks? bad mounts? bad scopes? What gives
     

  3. westcliffe01

    westcliffe01 Well-Known Member

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    If you ever dial, it should always be in the same direction, since every mechanism has backlash.

    So for instance, assume your scope has 8 min up dialed in and you would like to check your zero: Dial down to zero, then go to -2. Then stop and dial back up from -2 to zero. So to get to zero, you dialed UP from -2. Now if verifying your drop, as long as you rotate the turret UP, all is good. If you get to +12 and find you need +11, dial down to +9, then back up to +11. This way you reach your target adjustment by always dialing in the same direction. You will have to figure out how much backlash your turrets have and if that is acceptable to you.

    The same process has to be used for the windage turret too. You just have to decide if you go to target value while dialing left or right. Pick one way and be consistent.

    Take note of where your turrets are currently adjusted, then re-zero them using the technique described above, where you dial to the value it is currently set to in the up and left direction for example (a minimum movement of 2 min to reach the final value). Then check where the scope is really zeroed. Then shoot a 6 min box pattern at 100 yards by dialing the scope "normally" and then after re-zeroing shoot them using the backlash techniques described.

    Many people will find it a confusing concept and for them a new scope with precise reliable turrets is the only solution. Perhaps, (if there is 2+ min of backlash) the scope needs to be repaired if you trust the manufacturer to really fix the problem.
     
  4. D.Camilleri

    D.Camilleri Well-Known Member

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    Westcliffe01,
    Very good information. I have never thought about backlash in a scope turret, but I fully understand the principle. Basically the same as backlash on the feed dials on a metal lathe. The scope on my 300 that was giving me the fits in a Leupold VX3 6.5-20 with target turrets and 30 mm tube. I am still unsure on the variance in the windage since no adjustments have been made to the windage since the last time I had the gun out and it shot good to 760 yards.
     
  5. D.Camilleri

    D.Camilleri Well-Known Member

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    Well, I think I found the problem. Today I went out with the goal of redeeming myself and fill my antelope tags. Put a sneak on a group of speed goats and line up on one and dialed the scope. At the shot, I heard a contact and thought at least I am off to a better start. I found the doe in my scope and she was hit in the front leg. I tried several times to put another bullet in her as the herd got further away and no luck. I made a sneak from a different angle and shot a second doe and hit her low also. I got closer and finished her off and also finished off the first doe that I had hit. I wasn't very happy about the shooting, but stuff happens. I quartered out my animals with very little wasted meat and headed for the house. I slipped back out to the rifle range and checked my zero at 100. 1 1/2 inches low! I talked to a friend at the range and we discussed backlash in the turrets. I dialed up 3 min and then down 3 1/2 and up 1/2 to 0 and shot again. This time both shots hit right and 1 inch low. My friend came over and said maybe the problem is the bipod. I grabbed a piece of paper to check the clearance in the barrel channel and then loaded the bipod and he told me the paper got tight. I removed the bipod and set up with my front rest and first shot, bullseye. Problem solved. I usually hunt with shooting sticks and my backpack for a rest and usually only use the bipod for antelope. Time to clearance the barrel channel on the stock.
     
  6. Catfur

    Catfur Well-Known Member

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    What scope?
     
  7. MachV

    MachV Well-Known Member

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    Dang rifles anyway LOL
    My trusty old 7mag Ruger has had the same zero for 5 years but for some reason it took out 2 backstraps and a very high shoulder the other day.....Its going to the range for a checkup before it goes elk huntinglightbulb
     
  8. D.Camilleri

    D.Camilleri Well-Known Member

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    This gun has a Leupold vx3 6.5-20 with target turrets, dual dovetail mounts.
     
  9. westcliffe01

    westcliffe01 Well-Known Member

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    I don't believe in the dollar bill rule, more like doubled playing card rule to me... Most stocks I have seen flex enough that one needs close to 1/16th to keep it free floated under all conditions.
     
  10. angus-5024

    angus-5024 Well-Known Member

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    If its not fiberglass I go 1/16 on the sides and 1/8-3/16 on the bottom for float. For me loading a bi-pod is too important to not be worry free of fore end contact.
     
  11. D.Camilleri

    D.Camilleri Well-Known Member

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    Thanks, will do!