For you reloading scientist out there: Jump vs. Push

Discussion in 'Ammunition & Reloading' started by Squirrel_Slayer, Nov 11, 2010.

  1. Squirrel_Slayer

    Squirrel_Slayer New Member

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    I discovered last night that after changing brands of bullets that I have been seating my rounds far too deep into the case. After resetting my .223 die to seat the rounds to 2.260" that my manual calls for on my AR, I loaded up 100 rounds to shoot this weekend. Which brings me to my question. Has anyone out there played with the OAL for their AR handloads and found their rifles to shoot better with a little jump to the rifling or maybe loading to over max OAL and getting a little push into the rifling?:confused:
     
  2. lonyaeger

    lonyaeger New Member

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    I seat bullets for my AR just enough so that they will fit into the magazine and feed correctly. They shoot good.
     

  3. Squirrel_Slayer

    Squirrel_Slayer New Member

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    The 2.260 OAL in the manual has more than enough room to fit in the mag. I don't know how much jump to the rifling that provides though, and it changes with the different ogives from different bullets. I guess the only real way to figure it out is to to play with different OAL's but I was thinking that maybe everyone just loads to the 2.260 and doesn't mess with it? I just really wish that I hadn't been loading this whole time that I switched to MatchKings with the rounds way too far in. We'll shall see on Saturday how acurate my latest batch shoots. Using Lake City Brass with 25.4gr. of Varget behind 69gr. MatchKings. If I was poking paper I wwould post a range report, but since I am shooting at metal silhouettes, can't do it.
     
  4. Squirrel_Slayer

    Squirrel_Slayer New Member

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    Lon, who is that in your avatar? Amanda Peet?
     
  5. lonyaeger

    lonyaeger New Member

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    No, not Amanda Peet. Why do you ask?
     
  6. Squirrel_Slayer

    Squirrel_Slayer New Member

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    Just looked like her, but your new avatar is even more stunning, dang!!!
     
  7. lonyaeger

    lonyaeger New Member

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    It was Christy Canyon.
     
  8. JonM

    JonM Moderator

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    the seating depth ideal for your charge load can vary from bullet type to type and also vary by the powder and powder charge. best way to find ideal loads is to change only one variable at a time.

    when i used to tune my 308 rounds for long distance shooting i would start by selecting a powder and charge weight. once i find the rough accuracy then it was time to muck with seating depth. ive always thought of seating depth as fine tuning once i got the right channel.
     
  9. hunter Joe

    hunter Joe New Member

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    The one advantage to shooting a single shot is be able to adjust the OAL of the cartridge. In my T/C Encore 7mm-08 the projectile is set .010 of the lands. Makes for some mighty fine accuracy. I found that I can obtain good accuracy with different projectile/powder combinations.

    With my mag fed guns I'm pretty restricted to the magazine parameters. This does not mean you can't achieve superb accuracy, you just have to work at it a little harder.
     
  10. Squirrel_Slayer

    Squirrel_Slayer New Member

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    I single load my AR most of the time anyways but I haven't decided if this is even going to be a parameter that I am going to mess with yet or not.
     
  11. cpttango30

    cpttango30 New Member

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    You must be loading the 69gr or 77gr SMK bullets.

    1st NEVER EVER excede the max OAL. You must have bullets seated at least half the diameter of the bullet to get proper neck tension on the bullet.

    Now sure every rifle with have a sweet spot for OAL just like it will have a sweet spot for bullet weight or powder and charge weight.

    Now you can load to the lands some say OMG NO DON'T DO THIS. I will tell you you can load for a little crush you just have to adjust your load accordingly because it will cause an increase in chamber pressure. NOW if you are not very bright and running max loads DON'T EVER Load into the lands. back of my 15 to 20% and work up.

    Now because of the ogive some bullets will need to be seated out a little further than others. If you are loading a 180gr 30 cal VLD you can load it our further than say a 180gr 30 can round nose.