Using a 25 cal COAL gauge for a 264

Discussion in 'Reloading' started by The Oregonian, Jul 10, 2018.

  1. The Oregonian

    The Oregonian Well-Known Member

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    Question for the experts here...I just got my 6.5cr and bullets. I measured the lands using the Hornady OAL gauge, but just realized I don’t have a 264 insert for the comparator that attaches to the calipers....have one on order but it won’t be here for several days but am itching to go shoot it.

    I used the 25 cal insert to get a measurement of the lands, then backed off .020 to get bullet seating depth. I know the absolute COAL numbers will change and the measurement will be on a different point on the bullet when I use the 264 insert, but is there any reason I should be concerned about loading up some rounds and seating them .020 off the lands based on the 25 cal insert? The recipe that came with the gun (MOA Rifles) and their COAL using different gauges will be different than mine, so .020 off is what the recommend. I inserted the modified case and measured two separate times and got the same reading.

    Seems like it should be safe to use that depth and work up to their powder charge of 42.7 H4350 (2850 FPS) to ensure no pressure signs. Will likely go 41.0 and examine cases and velocity vs what they got the best results with.

    Am I fine with this? Haven’t loaded anything yet - better safe than sorry, but would like to get out to the range in the next day or two - but will wait if that is best path.
     
  2. can1010

    can1010 Well-Known Member

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    using the Hornady comparator is just a reference number it wont matter for load workup. find a load with the 25 cal insert and when your 6.5 cal. insert comes in check your loaded ammo and change your numbers. I use my 7mm on my 270 all the time seeing I load those the most
     
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  3. Rhovee

    Rhovee Well-Known Member

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    It isn’t very accurate. I did that for a while and where the .25 lands is not near the ogive. If you do use it, Mark and save the bullet you used for future reference. Take a handful and see how consistent they are using the .25 insert.
     
  4. The Oregonian

    The Oregonian Well-Known Member

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    I used several different bullets and all were within .002 measurement to the lands which should be fine for first session. I have the 264 coming in a few days and will recheck with that.
     
  5. brentc

    brentc Well-Known Member

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    You're fine to do that. I use a 25 cal insert for 264 bullets all the time. I also use a 30 cal insert to measure 338 cal bullets because the long nose of the Berger 338 bullets extends too far into the 338 insert that they touch the anvil.

    Additionally, if you were to try two separate Hornady inserts of the same caliber it is likely that you'll see two different readings. None of the comparator tools will measure exactly on the ogive across all bullet manufacturers. As long as any single insert references to the same place bullet to bullet it doesn't matter what numbers are stamped in the side of the insert as long as the hole in the insert is smaller than the caliber of bullet being measured.
     
    Last edited: Jul 10, 2018
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  6. The Oregonian

    The Oregonian Well-Known Member

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    Yes, understood the second part and was almost sure the 25 cal was fine but don’t want to assume things in reloading if I don’t know the answer.

    Thx for the help.
     
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  7. wboregon

    wboregon Well-Known Member

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    I'd agree with every one else here, It doesn't seem like a big issue, I use my 270 insert for measuring 7mm (small difference I know) always seems to give accurate readings.

    Also hello fellow Oregonian reloading person, where are you based out of, I see you around here a lot.
     
  8. The Oregonian

    The Oregonian Well-Known Member

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    I was in Tigard but moved 2 yrs ago....in Nashville now. Miss some thing about Oregon but not others.