Short range shooting

Discussion in 'General Rifle Discussion' started by cpttango30, Apr 22, 2010.

  1. cpttango30

    cpttango30 New Member

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    All the rage now is long distance shooting.

    But Short range shooting offers you a whole different set of problems and variables. I classify short range shooting at anything under 200 yards. 200 yards may be a long way to be shooting for some and for other it may just be a drop in the bucket.

    Like do you hold over or under for a shot at 25 yards with sighted for 100 yards?

    Do you need a boat tail bullet for shooting 200 yards or less?

    How do I sight my rifle in for shooting at targets that may present at 10, 25, 50 100 and 200 yards?

    How big is too big for scopes and optics?

    Do you even need optics at short ranges?

    Dose the height of the sights over the bore come into affect at short range?

    Do I need a long barrel for short range and how short is too short?

    I would like to discuss these in this thread.
     
  2. NGIB

    NGIB New Member

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    I will watch this one with interest. I asked a question yesterday about an ACOG vs an EOTech as I shoot at 100 yards or less and that's all I care about...
     

  3. cpttango30

    cpttango30 New Member

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    Do you hold over or under for a shot at 25 yards when sighted for 100 yards?

    Well that is a tough question. If you are sighted at 100 yards your bullet is exiting the barrel 1.5" or so below the line of sight. Your bullet will NEVER rise above the line of the bore but it may rise above the line of sight. As you can see in the accompaning ballistics chart i did for a Hornady 55gr factory load with a muzzle vel of 3240 fps. You will note that at 25 yards your bullet is still .8" below line of sight meaning if you held the sights on the bull of a target and all else is equal the bullet will strike .8" low so at 25 yards you have to hold over. As targets move closer you now have to compensate for the distance the centerline of the bore is away from the centerline of the scope or sights.


    Many new shooters get confused and think that if I have to hold over at longer distances then I should have to hold under the closer the target gets. That is not the case. I think about open sights like this. For this illustration your front sight doesn't move up, down, left or right. So if you keep your front sight on target and move your rear sight up you are moving the sight picture DOWN in front of the front sight. Think of the front sight as a fulcrum of a seesaw and as one goes up the other has to go down.

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  4. opaww

    opaww New Member

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    Great post and great subject, I will be watching this one.
     
  5. CA357

    CA357 New Member Supporter

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    Interesting thread.
     
  6. cpttango30

    cpttango30 New Member

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    Do you need a boat tail bullet for shooting 200 yards or less?

    This is another interesting questions we have before us. The boat tail is to help provide a more sleek profile of a bullet. This allows the air to flow off the base of the bullet more smoothly. All in all you don't see the affects of a boat tail till 200+ yards. Allowing the air to flow more smoothly allows for a bullet to retain energy longer. Thus not dropping as fast.

    As you can see below in the product information for a Hornady 50gr V-Max (boat tail) and a Hornady Varmint SP (Flat Base) bullets the V-max for the size and weight is a sleeker bullet with a Ballistic coefficient of .242 vs the 50gr sp BC of .214.
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    What are you talking about with a Ballistic Coefficient? Simply put it is how easy a given body fly's through the air (Ballistic Coefficient: Is a measure of a bodies ability to overcome air resistance in flight).

    As you can see in the charts Below the Boat tail bullet has less drop and would also have less wind drift at longer distances.

    With the price of bullets going up and up and up. I say buy the cheaper flat base bullets if you know your keeping your shots within 200 yards. AS you can see at 200 yards there is only .1" difference that is not a whole lot of difference if you are target shooting or hunting large game. But if you look at 400 to 500 yards. There is a big difference in drop and velocity drop off. At 400 yards your difference form flat base to boat tail is 2.3" and at 500 it is 5.8" different. In the varmint hunting world that is the difference between a red mist kill and a total miss. In deer hunting that could be a wounded deer running off to die a long painful death.

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