Reamer advice, please

Discussion in 'Gunsmithing' started by BTnerd, Apr 29, 2010.

  1. BTnerd

    BTnerd Member

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    I'm about to order a .243AI reamer. I intend to shoot 105-107 grain bullets, and I'd like to be able to seat them touching or slightly jammed if needed. With a 105 gr. bullet seated to a OAL of 2.820 (just a bit shorter than my mag box allows), there is about .180" from the case mouth to the place on the bullet measures .237. Should i specify a .180" throat or should I make it a bit shorter? If I get it wrong (too long) I may run out of magbox room.

    What are your opinions on throat angle? 1.5 degrees? does it really matter? All opinions appreciated, Thanks.
     
  2. trueblue

    trueblue Well-Known Member

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    Load a couple of dummy rounds to the COAL you want and send them to Dave Kiff @ PT&Gauge and they will make the reamer with the appropriate freebore to fit your round. The 1.5 degree is the way to go.
     

  3. NesikaChad

    NesikaChad Well-Known Member

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    +1 on calling David.

    When magazine lengths allow I try to seat my bullets so that the boat tail/bearing surface junction is just above the case neck/shoulder junction so that I don't have to deal with doughnut rings and the extra work. It takes advantage of case capacity, and makes for a very simple set up.

    Build the reamer accordingly
     
  4. shortgrass

    shortgrass Well-Known Member

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    You didn't mention what action you are using. 2.85 kind of implies a Rem. S.A. although I've measured a few others that are about the same. If it is a Rem. S.A. or a custom that uses Rem. S.A. components check out "Wyatt's Outdoors" extended magazine box made for the 700. It is easy for a 'smith to install and will give you a cartridge OAL of 3.050". The cost of this option might trump the cost of a 'special' reamer. P.S. I'm 'hooked' on removable pilot reamers, no 'scuffs' from a fixed pilot that way and you can choose the pilot that fits the barrel the best.lightbulb
     
  5. BTnerd

    BTnerd Member

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    Thanks for the input ! Yes, it's a 700 shorty (actually a m7). I am going through PTG, and for sure am going removable pilot this time. I can't get the 105's heel into the neck with this magazine length. I'll have to give the Wyatts some thought...
     
  6. shortgrass

    shortgrass Well-Known Member

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    The longer box allows you to set bullets out further as the throat wears. May extend the 'acceptable accuracy' of your barrel, so to speak.