6mmx47 lapua .100 thousands short 40° shoulder

Discussion in '6BR, 6BR Improved & Wildcats' started by Stan Taylor, Nov 16, 2017.

  1. rewinder

    rewinder

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    5 yrs ago I cut .140 off the bottom of a 6/250 AI sizing die and used it to collaspe the 30 degree shoulder on the 6.5 x 47 lap to a 40 degree shoulder. Same as the SLR pushes down the shoulder on a 243 case down to 30.. The shoulder dia. on the 6/250 AI is smaller than the 6.5 x 47 and you lose some case cap. Had right at 44.5 gr. water weight cap. Was looking for a Hunter class 6mm case for Score shooting. Randy
     
  2. Stan Taylor

    Stan Taylor

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    Well I screwed on a new barrel an fired 10 pieces of new brass threw it to get some once fired brass loaded the same charge of H4350 an velocities was slower than the old test barrel about 50 fps to 2980 fps instead of 3040 or so new barrel may be slower but time will tell shot same load of varget as the R 15 same thing speed was a little slow but the accuracy I like what I am seeing examine pics below that is all for now weather permitting will try a little more tomorrow.PS 5shot groups I was shooting 103 vapor trail Sierra jackets
     

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    Last edited: Dec 1, 2017
  3. kneedtospeed

    kneedtospeed Silver $$ Contributor

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    Damn Stanley,
    You got that criterion hummin! LOL
     
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  4. Stan Taylor

    Stan Taylor

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    Humm
     
  5. urbanrifleman

    urbanrifleman Silver $$ Contributor

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    So would this be the same as a longer 6BRA?
     
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  6. Stan Taylor

    Stan Taylor

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    This case is about .200 thousands longer than the the BRA case overall length.
     
  7. urbanrifleman

    urbanrifleman Silver $$ Contributor

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    Right. But the shoulder and neck length appear to be the same. Which would make sense to me.
     
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  8. Stan Taylor

    Stan Taylor

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    There is a pic of a BRA case that is similar to the regular bra on page two of this post an a dasher an this 6mmx47 40° short for comparison in case you missed it.
     
  9. urbanrifleman

    urbanrifleman Silver $$ Contributor

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    I admit I get confused with all these wildcats. The 6BR ackley is simply a 6Br with a 40 degree shoulder right? No other changes? The neck is still full length right?
     
  10. Stan Taylor

    Stan Taylor

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    Yes sir really close to same length.
     
  11. urbanrifleman

    urbanrifleman Silver $$ Contributor

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    So I am just asking. Is your cartridge the same shoulder and neck length as the 6bra? Which would be a 6BR neck length with a 40 degree shoulder?

    I mean that would make sense to me. Just extend the body and leave the other geometry the same. Then you are trying to get into the node optimum for the 4350 type powders. Right?
     
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  12. Stan Taylor

    Stan Taylor

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    Yes sir you are pretty much on point the h 4350 is about 37.8 grains at 3030 fps easy on case's.
     
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  13. urbanrifleman

    urbanrifleman Silver $$ Contributor

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    Oh man... I bet that kills... You should try R16. :)
     
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  14. Stan Taylor

    Stan Taylor

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    Yes I intend to as soon as I get some.
     
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  15. urbanrifleman

    urbanrifleman Silver $$ Contributor

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    This looks like a great design.
     
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