Lets hear some techniques for finding c.o.a.l

Discussion in 'Ammunition & Reloading' started by dustinoif3, Sep 27, 2012.

  1. dustinoif3

    dustinoif3 New Member

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    I've heard several different ways. One using a dowl rod to the face of the bolt, put a mark then drop a bullet into the chamber while using a dowl to push the bullet to the lands then insert dowl down barrel to tip of bullet. Sounds feasible. Problem is the ogive of bullet. I guess if your using the same brand of bullet they will be pretty close. I've heard of the dummy bullet and sharpie trick. Them just breaking down and getting the chamber gauge and comparoterand bullet comparator
     
  2. dustinoif3

    dustinoif3 New Member

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    I was trying to add till my phone jacked up that I'm loading for my Remi 700 .308. Also opinions on full length resizing or neck sizing for bolt guns. Thx in advance
     

  3. locutus

    locutus Well-Known Member Supporter

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    I like neck siZing for bolt guns. Just my personal preference, I can't prove it's better.

    An easy way to find a useablw COAL is to put a factory rounf of the same bullet weight in the seating die, and slowly turn the seater stem down until the seater touches.

    A good Sinclair measuring tool is better, but the factory round works pretty well.
     
  4. dustinoif3

    dustinoif3 New Member

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    Yeah that's the technique I use for my pistol loads. I'm looking to find the lands so I can work back to find the sweet spot
     
  5. The_Kid

    The_Kid New Member

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    I neck size only in all of my bottleneck cartridges; lengthens the case life.

    I seat all my bullets to the cannelure, or, (if no cannelure,) I seat them close to, (if not at,) the suggested length in my reloading manual.

    Works for me... today's shot;
    [ame="http://www.youtube.com/watch?v=TeEXvG2lr3E"]Win94ae 30-30, 3 Inch Target, 350 Yards[/ame]
     
  6. The_Kid

    The_Kid New Member

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    I partially neck size a case as to snugly hold a bullet from gravity but can be pushed in easily. Insert a bullet so it sticks out a good deal. Chamber that round then eject it as to not let it fall; measure the COL. Repeat the chambering process as to make sure that length is correct.
     
  7. dustinoif3

    dustinoif3 New Member

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    I've heard of that method. Seems pretty fool proof. Someone told me to that I should full length size new brass or brass that came from a different rifle. Then once it's fired from your rifle and has expanded to the chamber to neck size from there on out. That method for bolt guns only. Seems to make sense for building a round just for your rifle.
     
  8. steve4102

    steve4102 New Member

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    True, but with each firing the brass case continues to grow, so the way the neck sized brass fits into the chamber will be different with each consecutive loading. As the brass continues to grow at some point you will have to FL size and bump the shoulder back. Depending on the rifle and the load that may come after only a couple firings or it may take many firings.

    This is how Nosler recommends finding your specific OAL.

    http://www.thefirearmsforum.com/showthread.php?t=97328&highlight=coal

    Me, I use the Hornady/Stoney Point Gauge.
     
  9. grandpabear

    grandpabear New Member

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    That is exactly how I do It. A couple of times to verify and that method works better than any gauge you can buy. IMO After I get the measurement I shorten up by .030 and start working it.
     
  10. dustinoif3

    dustinoif3 New Member

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    Awesome. I've heard that .010 is the closet you wanna be to the lands. Correct? So if I start at .030 and go in increments of 5 I should be tracking. Also has anyone ran into not being able to use the magazine when loaded out farther than manual col?
     
  11. dustinoif3

    dustinoif3 New Member

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    Also thank you Steve for posting that link. Very helpful thread!
     
  12. noylj

    noylj Member

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    Measure length from muzzle to breech. Write down this number.
    Remove barrel from gun.
    Resize two cases.
    Drop in barrel or cylinder. They should "plunk" right in and fall right out when you turn barrel or cylinder upside down.
    Expand both cases and ensure there is enough flare/bell at the case mouth that a bullet can be lightly pressed into the case and will stay in place when you turn the case(s) upside down.
    Drop bullet in barrel and push very lightly into lede/leade/rifling.
    Measure distance from muzzle to bullet tip.
    Subtract this number from the muzzle-to-breech number. This is your Max COL for THAT bullet in THAT barrel.
    For a revolver, you want the distance out that a bullet can be seated and not extend beyond the cylinder. You can do this by removing the case mouth flare just enough so the case chambers, then placing the round with the pressed in bullet into the cylinder and seeing if it chambers. If not, gradually seat bullet until the round does chamber. Be sure it chambers in all chambers (is there a different name for the chambers of a cylinder?). This will be max COL for that bullet in that cylinder.
    Now, your goal is to establish a COL that fits the magazine, feeds, and chambers in your gun.
    Since there is no powder or primer in the two "rounds," we can safely play.
    Seat the bullet to the cartridges max SAAMI COL (9x19: 1.169: MAX and 1.000" Min; .40S&W: 1.135" MAX and 1.085" Min; .45 Auto: Match (SWC)--1.255" MAX and 1.140" Min, Std (FMJ, etc.)--1.275" MAX and 1.190" Min).
    Try the max COL and see if the two INERT rounds will fit in the magazine and feed and chamber. Watch for bullet set-back.
    Rounds will probably NOT pass all three requirements.
    Seat bullets gradually deeper until both inert rounds function properly.
    This is the MAX effective COL for that bullet in that gun.
    Now, load up 5-10 rounds at this COL. Then load up several other sets of 5-10 rounds at progressively shorter COLs, not to go below the minimum COL in manual being used and certainly NOT below the SAAMI minimum COL.
    Take these to the range and fire them from a rest for accuracy. It is possible that some of the very long COL rounds and some of the very short COL rounds will not fully function for all 5-10 rounds. Unless you see some problem with the round itself, consider that COL to fail. You should easily find the mid-range COLs all feed and chamber easily and, if you shot carefully, you can even get some idea if a certain range of COL is more accurate.
    This will establish the proper COL range for that bullet in that gun.
    Now, that COL will "probably" also work for many other guns in that caliber, but it will probably NOT be optimum in the other guns.
    Your shooting and loading will establish what COL works best for your and your needs.
    In my experience with my guns, 9x19 is by far the most fussy cartridge in terms of COL--too long or too short will produces a jamamatic and the "sweet spot" for accuracy in very fine and EVERY different bullet will do best at its own COL.
    .45 Autos seem the least finicky and do very well with a wide range of COL and will, at least all most all mine will, feed an empty case without any trouble.
     
  13. TLuker

    TLuker Active Member

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    Everything there sounds about right to me. And I can't use the magazine on my .308. One more thing to keep in mind is to make sure your bullet is deep enough in the case for the case to get a firm hold on the bullet.
     
  14. TLuker

    TLuker Active Member

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    Oh, and go ahead and get the Hornady Loc-n-Load set-up. It is the way to go. :)
     
  15. steve4102

    steve4102 New Member

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    The closest you want to be is where you get the best accuracy. That could be into the lands to .xxx off the lands.

    When adjusting OAL for accuracy it's best to start as long as you can and seat deeper as you go.

    Seating deeper will decrease pressure and keep your loads in the safe pressure zone.

    Starting short then increasing OAL will increase pressure and you may find yourself with a high pressure situation the closer you get to the lands.

    This is for bottle necked rifle rounds, straight walled and pistol rounds work just the opposite.
     
  16. dustinoif3

    dustinoif3 New Member

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    Okay. I would like to add something else to this. I know I've read it in some other threads a long time ago but generally what do you guys prefer to do first. Play with oal or play with powder charge? Also I've seen the hornady lock n load set up. Currently my platform is my dillon 550b and an ol Lyman single stage. I don't like knocking on other progressives but I think death will be the only way I part from my 550. Hahaha
     
  17. locutus

    locutus Well-Known Member Supporter

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    Some of my loads are .005 off the lands.

    Remember that measuring from the tip of the bullet is not accurate. Use a comparator so that you're measuring from the point on the bullet's ogive where it becomes groove diameter.

    That's why I like the Sinclair tools.

    You may well find that your most accurate load will not fit the magazine.

    Then you have to decide if that 1/8 inch you gained in accuracy is worth single loading. IMHO, it's not.
     
  18. Coyotenator

    Coyotenator New Member

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    I use the Hornady Lock-N-Load O.A.L. gauge too, and recommend it highly.

    I like it that you measure with the bullets that you're loading.
     
  19. The_Kid

    The_Kid New Member

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    I use that method with my lever action also.