The GUN Forum

Find answers, ask questions, and connect with our
community around the world.

home Forums – The GUN Forum Ammunition Reloading Bump gauge vs comparators…vs homemade bump gauge

  • Bump gauge vs comparators…vs homemade bump gauge

    Posted by james on August 6, 2022 at 9:32 am

    I am just starting to get on my bench and learn to reload .223
    I typically tend to put the cart before the horse, and being new to reloading I thought it would be smart to get multiple instruments for measuring. I think I’m just overthinking things and confusing myself, but hoping someone will set me straight.
    I bought a Sinclair bump gauge, the hornady headspace comparator, and made my own bump gauge with an old case.
    When setting up my full length die to set the shoulder bump: The hornady and homemade gauge will produce the same measurements every time, but the Sinclair will show a different measurement. I.E the Sinclair gauge will show .0095 in bump while the other two only show .0045 in shoulder bump.
    Is the Sinclair gauge I have maybe out of spec? Or am I using these gauges incorrectly?

    james replied 1 week, 4 days ago 2 Members · 1 Reply
  • 1 Reply
  • BigWobbles

    August 6, 2022 at 9:32 am

    It’s not an absolute number: the gauges are contacting a datum at different places. You’re fine as long as you measure everything (fired unsized vs fired sized) with the same gauge.

Reply to: james
Your information:

Start of Discussion
0 of 0 replies June 2018