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Thread: 262 or 268 necks for 6mm PPC

  1. #31
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    I havenít read through all the posts, so maybe itís been mentioned. I switched from a .262 neck to a .268 when I started shooting boattail bullets. With a 30.0 grain load of 133 the boattail bullets simply wouldnít stay put. Youíd have several different seating depths by the time you got to the bench. It didnít matter how much neck tension you used the .262 couldnít hold them.

    The flat base bullets tend to stay put better since they have a pressure ring to help hold them.

    Bart

  2. #32
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    Quote Originally Posted by Bart View Post
    I havenít read through all the posts, so maybe itís been mentioned. I switched from a .262 neck to a .268 when I started shooting boattail bullets. With a 30.0 grain load of 133 the boattail bullets simply wouldnít stay put. Youíd have several different seating depths by the time you got to the bench. It didnít matter how much neck tension you used the .262 couldnít hold them.

    The flat base bullets tend to stay put better since they have a pressure ring to help hold them.

    Bart
    It seems logical that a thicker neck will hold a compressed load better with boattails.
    Just have to ask, have your aggs improved in the 100/200 environment with boattail bullets?

    Interestingly, going through Ferris Pindells notebook his most improved test loads were with a 0.266" neck (and 40 degree shoulder). All the tooling I had previously bought from Ferris was 266/40.

    More than once, in his latter days, was notes that he wrote "the first 6 went exactly through the same hole".


    .

  3. #33
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    Jerry,

    I decided it was time to switch when i was setting at the bench and I could see my bullets growing. To the point a couple came completely out of the neck sitting on top of the powder. I let Billy shoot the .268 for a year before I switched just to be sure there were no problems. Accuracy wise I donít think thereís any difference. A properly turned neck with the correct amount of clearance will shoot equally as good. However the .268 necks will hold a boattail in place where a .262 with the same load canít.

    Bart
    Last edited by Bart; 11-17-2018 at 01:34 PM.

  4. #34
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    Thumbs up Right On !

    Quote Originally Posted by Bart View Post
    Jerry,

    I decided it was time to switch when i was setting at the bench and I could see my bullets growing. To the point a couple came completely out of the neck sitting on top of the powder. I let Billy shoot the .268 for a year before I switched just to be sure there were no problems. Accuracy wise I don’t think there’s any difference. A properly turned neck with the correct amount of clearance will shoot equally as good. However the .268 necks will hold a boattail in place where a .262 with the same load can’t.

    Bart

    Good point Bart! Now we're getting to the bottom of the reasons for the trend toward .268 and .269 necks. I'm glad I followed Jackie Schmidt's lead of .269 long ago with my Beggs cartridges. Lately, I've been concentrating on the 6Beggs No-turn with a .274 neck. No neck turning at all!

    Hey, I wonder how the 6PPC would work with a .274 No-turn neck? ! Huh?

    Me? I'll stick with my 6Beggs no-turn but for those that believe there's something special about the PPC's Ackley body taper and 30 degree shoulder angle, a no-turn 6PPC might be just the thing! One of Richard Brensing's associates is already doing very well shooting Norma cases no-turn in his 6PPC. I believe he is using a .269 neck. Something to think about; huh?

    But of course if you're gonna' continue using Lapua 220 Russian cases as most of us will, you will have to go to at least a .273 neck in order to have the optimum clearance on the loaded round.

    And hey; lots of PPC shooters have been living with outdated chamber reamer designs requiring the use of expensive custom sizing dies when now may be the time to upgrade to a new reamer with more desirable dimensions. JGS, PT&G and other reamer manufacturers will just be delighted to help you and the cost of a new reamer is insignificant when compared to other items required by this madness we call benchrest.

    For the 6PPC, my specs on a new reamer would be:

    * .268 for a tight neck chamber using Lapua brass. .273 for no-turn.

    * .4420 dimension'A', (.200 in front of the extractor groove.)

    * .4310 at the shoulder before beginning of radius to shoulder angle.

    * .040 freebore, .2435 diameter. (can use either flatbase or boattail bullets.)

    * Case overall length (base to end of neck) 1.510.

    * Of course, one and a half degree leade angle.

    Let's see what everyone thinks of this; huh?

    Later,

    Gene Beggs

  5. #35
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    Gene,

    Iíve got one just about like that except with a Improved 40 degree shoulder!

    Bart

  6. #36
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    Quote Originally Posted by Bart View Post
    Gene,

    Iíve got one just about like that except with a Improved 40 degree shoulder!

    Bart

    As Jerry pointed out, Ferris Pindell was high on the 40 degree shoulder. I'm sure he had his reasons.

    Good luck in 2019.

    Best regards,

    Gene Beggs

  7. #37
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    Quote Originally Posted by Gene Beggs View Post
    When the PPC cartridge was introduced in the late sixties and early seventies Palmisano and Pendell used the SAKO 220 Russian case which had much thinner neck walls than the Lapua and Norma cases in use today. Consequently, it was necessary to turn the necks to around .0080 to .0085 in order to completely clean them up which resulted in chamber neck diameters of .2620 and often .2610.


    Gene Beggs
    I ask Ferris once why the original PPC had a 262 neck and he said the brass they had at that time required a 262 neck to clean up.

    .

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