bwaites Wrote:Am I looking at a compound throat from Dave Kiff? I'm not an expert on reading these, but that's what it looks like to me?
Yup. See that .2435 and .2398 "staged, variable taper in the leade/throat area".....
That's a compound throat. From the article:
Quote:Radical New Reamer Design from PT&G
Experts should look at the leade angle(s), freebore, and throat dimensions. You may be surprised. Dave Kiff of PT&G says this Bore Rider design has worked successfully for other cartridge types/calibers as well. Apparently this design helps the bullet center up smoothly in the bore before the bullet engages “hard” in the rifling — or so we’ve been told.
The funny thing is that a compound throat doesn't work well in higher pressure chamberings because anything much over 55,000psi will plasma cut the shallow initial leade before the conventional one.
I wonder what other cartridge types/calibers they are referring to where this design has been so successful?
NRA Basic, Pistol, Rifle, Shotgun, RSO
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6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
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CCW, CQM, DM, Long Range Rifle Instructor
6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
www.AR15buildbox.com