Turner Slings
+ Reply to Thread
Results 1 to 5 of 5

Thread: "The Lyman 48 rear sight for dummies"?? :)

  1. #1
    Join Date
    Aug 2009
    Location
    NW Washington State
    Posts
    5,171

    Default "The Lyman 48 rear sight for dummies"?? :)

    I purchased a Griffin & Howe-modified NRA Sporter with Lyman 48 rear sight and don't have a clue about how to operate the rear sight. I tried reading Crossman's "Book of the Springfield" and read his detailed description and ended up getting a headache and needing to lay down! I think I understand the windage adjustment but am totally lost on elevation, other than the mechanical act of doing so.

    Anyone got a link or good source for information? As I know there are different models, a couple of pictures of my rear sight below. I tried sighting it in the other day at 100 yards and let's just say my results were rather "modest"!

    TIA!







    "We make men without chests and expect from them virtue and enterprise. We laugh at honor and are shocked to find traitors in our midst."
    --C.S. Lewis

  2. #2
    Join Date
    Aug 2009
    Location
    Jackson, Mississippi
    Posts
    3,843

    Default

    I think for target work you should find one of the screw in apertures. The big hole is okay for minute of deer. There is backlash in these sights so you have to move it enough to take up the slack when you change direction.

    http://www.aperturesnmore.com/produc...&categoryId=10
    Phillip McGregor (OFC)
    "I am neither a fire arms nor a ballistics expert, but I was a combat infantry officer in the Great War, and I absolutely know that the bullet from an infantry rifle has to be able to shoot through things." General Douglas MacArthur

  3. #3
    Join Date
    Aug 2009
    Location
    Indiana
    Posts
    617

    Default

    Rick, you may find some useful information on this site:

    http://www.lasc.us/Brennan_7-3_Sights.htm

  4. #4
    Join Date
    Aug 2009
    Posts
    392

    Default

    Hi,
    I shall try to simplify the use of the Lyman 48 sight for you. I believe that you have one of the middle series of sights which has ½ minute adjustments. To make an elevation adjustment, unscrew or loosen the knob on the front of the base. After each adjustment, retighten this adjustment. If this is unscrewed and pushed in- the arm can be removed by sliding it up. If you look closely at the elevation knob you will see that starting at “0” and rotating CW (clockwise) through to “0” again (ONE through FOUR) before returning to “0”. You will also notice that one revolution of the elevation knob raises the elevation arm one “tick” or line on the elevation scale. Since it is mounted on a M1903 action with what appears to be a M1903 barrel, this complete revolution raises the elevation~ FIVE MOA (minutes of angle)”. (The Lyman 48 was designed with the M1903 in mind and the calibration is calculated for a M1903 with a 24” barrel. Other barrel lengths, will affect the calibration) This is ~five inches for each hundred yards. You will “feel” 10 detents as you do this. Each detent is ½ MOA. Since this appears to be an early sight, rotating the elevation knob CW (the elevation staff has a left-handed thread) will raise the LOS (line of sight) and the bullet impact. If you are sighting in at 100 yards and are shooting 2 inches low, simply rotate the knob clockwise two major marks on the elevation knob, or four detents or clicks. Each division (tick) on the elevation scales represents one complete revolution of the elevation knob or five mminutes.
    The windage scale plate is marked in “points”, a measurement known only to God and the US Army of the 20’s and 30’s. Actually a “point” is 4 MOA on the M1903 sight and 6 MOA on the Krag sight. There are no marks on the windage knob so it is more difficult to use than elevation. . It has a right handed thread so that turning the windage knob CW will move the sight and the POI (point of impact) to the left. The windage knob has detents every ½ minute so if you are shooting TWO inches to the right at 100 yards, rotate the windage knob FOUR “clicks” CW. Four “clicks”= two minutes with the ½ minute click arrangement. When you have established what you believe is that magic figure of “Zero” loosen the windage scale screws and move the plate to alight the “0” mark and the mark on the aperture. Use this as your reference.
    If you find that your elevation knob rotates from “0” through TWO and back to “0” then it probably has ¼ minute adjustments or 1/4th minute per click.
    I hope this helps.

  5. #5
    Join Date
    Aug 2009
    Posts
    392

    Default

    Lyman 48 Follow On
    Crossman makes the adjustment of the Lyman 48 too difficult because he wants to set everything to ZERO. As a High Power rifle shooter, I never did this. I always sighted in from 200 yards. When I established my 200 yard elevation setting, the elevation may or may not read “0”. I would then turn the elevation knob down until it rested on ZERO, counting the clicks as I went. I would then move the elevation pointer to the zero mark on the elevation slide. I would then turn the elevation up as many clicks as I had counted down. For example, if when I was sighted in at 200 yards, the elevation knob rested on the first mark past the “2”. I would lower the elevation knob 5 clicks (5 x ½) = 2 ½ minutes. I would then zero the pointer on the elevation slide at “0”. I then returned the elevation up to where my elevation knob read “2 ½”. My 200 yard zero is now +2 ½ minutes. My 300 yard setting would be to raise the elevation THREE minutes or TO A READING OF 5 ½. This is indicated by turning the elevation knob CW until it is 1 click beyond ZERO on the knob plus just above the first marker on the slide. Remember each “click is ½ minute. Likewise I never reset the range indicator on my M1. Everyone I knew and those who taught me just counted clicks. Zero the rifle at two hundred , then count the clicks down to find your 200 yard setting. All sight adjustments on the M1 were mae using the “click” counting system as a start.
    On the windage scale, I would try to establish a windage zero, and then set the windage scale “0” so that the index mark on the aperture was aligned with “0”. . Each marker on the windqge scale is a point or 4 minutes. If I wanted 5 minutes of left windage I would move the aperture two clicks past the first mark past to the left of zero on the windage scale.
    Consistency does not seem to be a virtue of Lyman 48’s. When the ¼ sight was introduced, it came in two versions. A left hand version for the Winchester 54 & 70 and later the 721&721 was added. Evidently the windage screw and the aperture was the same on sights, right mount and left mount. . When mounted on the right side of the rifle (03, Rem 30, etc) turning the knob CW provided LEFT windage. When mounted on the left side (a la 54, 70, 722) moving the windage knob CW provided RIGHT windage. I will admit that later on, Lyman did add arrows and a scale to the windage knob and the elevation knob. The ¼ minute sight only provided three minutes per revolution and the magic “point” marking had disappeared. Theoretically when the elevation lock nut is tightened, it takes all of the slack out and no lost motion exists. Practically, we always approached a setting from the same direction. To add elevation, we merely raised the elevation, to take off elevation, we lowered the sight past where we wanted to be and brought it back up to the desired setting to remove the slack.
    Hop e this helps further.

+ Reply to Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts