Don't forget to test seating depth of bullets...

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Fiftydriver, Sep 16, 2004.

  1. Fiftydriver

    Fiftydriver <strong>Official LRH Sponsor</strong>

    Messages:
    6,848
    Joined:
    Jun 12, 2004
    Don\'t forget to test seating depth of bullets...

    To all,

    I just finished restocking and bedding a stock for a customers Ruger M77 MkII in 270 Win.

    The stock was supplied by the customer and was a Boyds JRS classic which I really like the looks of this stock for a sporter stock.

    Boyds really screws up the bottom angled action screw by making their stocks thicker then a factory trigger and this results in the need to rebuild the bottom end of the stock to realign the action screw to the hole in the reciever, then the floor plate and catch need to be adjusted to fit properly.

    Anyway, back to my point.

    The customer stated that he wanted to shoot factory Rem 130 gr ammo so when the bedding cured after my three day waiting period, I headed to the range with this factory ammo to test.

    Before the bedding the rifle grouped in the 2 to 2.5" range with this ammo with most of the group size coming from horizontal stringing, typical problem with poor bedded rifles, especially flat bottomed receivers.

    After the bedding job I retested and the rifle was printing consistant 1.1" to 1.2" three shot groups in perfect triangles.

    This generally tells me that the bedding and bolt lugs are all square and baring true to get perfect triangles, still the group size was bothering me.

    I decided to try one of mystand by handlods for the 270 which uses a stout dose of RL-22 under the 130 gr Ballistic Tip adn lit with the CCI-200 primer.

    I found that the throat on thos 270, like most of them was extremely long. I was able to seat the 130 gr B. Tip to an overall length of 3.400" which is about as long as I could go and still have it feed reliably out of the magazine. This length was still 0.030" off the lands.

    I went back out to the range and shot three rounds down range. The first shot was about 1" up and to the right of the second two which landed touching each other.

    I have found this after shooting one brand of bullets, and then shooting another brand without cleaning, the first shot is generally a little wide of the group. this was no exception.

    I let the rifle cool and fired three more shots, these three cut a .315" ctc cloverleaf. Just like the last two of the first group did. Testing was over.

    When the owner picked up the rifle I explained to him that and showed him the groups on how his rifle performed better with the longer seated hand loads. He said he would start loading this round and use the load I shot in the rifle.

    Remember that seating depth can have a dramatic effect on accuracy. Test those seating depths.

    Good Shooting!!!

    Kirby Allen(50)
     
  2. Perkules

    Perkules Well-Known Member

    Messages:
    179
    Joined:
    Dec 11, 2002
    Re: Don\'t forget to test seating depth of bullets...

    Yes Sir.

    A micrometer adjustable 338 LM seater is sitting in a box on my living room table right now. Got another bullet to test, I figured this is the way to go.
     

  3. Guest

    Guest Guest

    Re: Don\'t forget to test seating depth of bullets...

    Kirby

    As usual...Outstanding information. Thanks a million

    Joe