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OAL OF LOAD

I HAVE WORKED WITH GUNS AND LOADED MY OWN AMMO FOR THE LAST TEN YEARS. i HAVE NOT EVER TOOK THE TIME TO REALLY GET THAT SERIOUS ABOUT FINE TUNING ANYTHING. THIS IS WHAT I HAVE AND WHAT I WOULD LIKE TO LEARN HOW TO FINE TUNE THE BEST LOAD I CAN AND HAVE CONSISANT ACCURACY. I HAVE A THOMPSON CENTER ENCORE WITH A 25-06 BARRELL. I WOULD LIKE SOMEONE TO EXPLAIN TO ME WHAT THE BEST WAY IS TO DETERMINE THE OAL OF THE LOAD I AM WORKING ON IS BEST FOUND. IN THE PAST I HAVE ALWAYS JUST GONE BY THE LOAD DATA IN THE BOOKS AND COMPARED THAT WITH WHATEVER BULLET I WAS USING. I AM AT THE POINT WHERE I NEED TO LEARN MORE AND KNOW HOW TO EXACTLY DETERMINE WHAT LENGTH I NEED TO GET THE BEST ACCURACY AND PERFORMANCE. IN THE PAST I MEASURED FACTORY LOADS OR WENT BY THE BOOK THE BEST I COULD. I UNDERSTAND THAT DIFFERENT GUNS, BOLT ACTIONS, AUTOS, LEVERS, SINGLE SHOTS ALL ARE DIFFERENT WHEN DETERMINING THE OAL OR WHATEVER. I'M JUST ASKING IF ANYONE CAN TELL ME THE PROPER WAY TO GET WHAT I AM LOOKING FOR. THANKS

Comments

  • bpostbpost Member Posts: 32,664 ✭✭✭✭
    edited November -1
    Welcome to the forums. [:D]

    One suggestion, turn the caps lock off, in the computer world it means you are shouting and is harder to read.

    To determine the OAL to the lands involves dropping a bullet into the barrel letting it rest against the lands. Holding it there with a dowel rod insert a cleaning rod, CAREFULLY, into the muzzle touching the tip of the bullet. Make sure the rod does not have a hollow end, it will give false readings. Mark the rod, again, carefully with a razor blade at the muzzle.

    Now, remove the bullet and close the action. Push the rod in to the receiver face and again mark the rod at the muzzle again. Carefully measure the distance between the marks. That measurement is the OAL for that bullet to the lands. You can now load a ladder with various measurements, from touching the lands to what is called a jamb fit and trying some starting about .020 off the lands.

    Most rifles like a round with the bullet just touching the lands and up to a .020 jamb into the rifling. Most accuracy is also found with high load densities and max or near max loads.
  • wvhillbillywvhillbilly Member Posts: 17 ✭✭
    edited November -1
    Thank you for the information, that is what I was looking for. Sorry about the caps lock being on.
    Once again thanks, I will probably have more questions in the future.
  • 1fisher1fisher Member Posts: 1,012 ✭✭
    edited November -1
    Another way is to take an empty brass and make a fine cut down the length of the neck so that a bullet will fit snug, but can slide down into the case with a little pressure.
    You just stick the bullet into the neck as far out as you can and then press it into the chamber. You should be able to feel when the bullet hits the lands - just push in the brass until it is fully chambered (the bullet will slide back into the neck) and then carefully remove the cartridge and measure its OAL.

    Bpost has given you the most accurate way to work measure it (other than a chamber cast), but this method will work if you do it carefully.
  • JustCJustC Member Posts: 16,056 ✭✭✭
    edited November -1
    http://www.sinclairintl.com/images/thumb/59-4000-t.jpg

    this is a tool made by sinclair that takes all the guesswok out of it
  • n/an/a Member Posts: 168,427
    edited November -1
    quote:Originally posted by JustC
    http://www.sinclairintl.com/images/thumb/59-4000-t.jpg

    this is a tool made by sinclair that takes all the guesswok out of it


    +1

    I've found most of my rifles like the bullets seated about .005" off the lands. I have not experimented with seating into the lands yet, though. I've done very little shooting/reloading over the last 3 years. It's hard to get motivated when you don't have a 500 yard range outside your back door, and 1000 yards on the other side of the property anymore...
  • cash777cash777 Member Posts: 213 ✭✭
    edited November -1
    If encore uses an extractor rather than an ejector romove the barrel. start out long on your oal. drop it in the chamber and gradually seat the bullet untill the rim is flush with the face of the chamber.Once flush, assemble and check to make sure you have full lock up on the action. from there you can adjust your seating depth. maybe slightly longer or shorter-- I use this on my contender. if you neck size --size untill you have lock up without moving the shoulder back. Hope I explained this well enough. seating depth from there may vary for accuracy in you gun-just watch for Max loads if trying to seat right up to the lands. Best Dave And all of the above.
  • wvhillbillywvhillbilly Member Posts: 17 ✭✭
    edited November -1
    Thanks guys for all the info, everyone has been very helpful. From what I come up with my OAL resting on the lands is 3.200. The bullet I am using is nosler 100 grain ballistic tip part number 25100. I have been testing with Hodgden H4831 that is what I would really like to use because I have plenty of it. Can someone explain what the difference is between H4831 and H4831sc? Cash777 can you explain what you mean when you say just watch max loads if trying to seat right up to the lands. Before I go any farther any help from here would be greatly appreciated.
  • JustCJustC Member Posts: 16,056 ✭✭✭
    edited November -1
    H4831sc is simply a shorter kernal of the original H4831. Same burn rate
  • cash777cash777 Member Posts: 213 ✭✭
    edited November -1
    Just on the side of caution to start.You know to never start testing loads with maximum charges. If testing with bullet touching the lands ,start within reccomended load information and work up watching for pressure signs. Thats all! Best, Dave I,m curious on the oal you come up with- Nosler# 6 reloading manual gives S.a.a.m.i at 3.250. I would of guessed yours would be longer than this touching the lands.
  • n/an/a Member Posts: 168,427
    edited November -1
    quote:Originally posted by cash777
    Just on the side of caution to start.You know to never start testing loads with maximum charges. If testing with bullet touching the lands ,start within reccomended load information and work up watching for pressure signs. Thats all! Best, Dave I,m curious on the oal you come up with- Nosler# 6 reloading manual gives S.a.a.m.i at 3.250. I would of guessed yours would be longer than this touching the lands.



    ...almost definitely.
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