02-25-2016, 01:33 AM
Drillboss Wrote:Let's not slam Shilen too hard about not using a SAAMI chamber. I believe they use an AA reamer design from before SAAMI certification. Best I can tell, it's within a few thousandths of SAAMI and uses the same 0.3" neck and the compound throat. Here's a copy of the reamer drawing they sent me about a year ago.
Pacific Tool 6.5 mmGrendal (AR).pdf
That looks like a SAAMI chamber to me, since you have the .300" neck, .2644" dia. just in front of the neck where the freebore is, and then a .2617" dia. at the point where the target leade begins. You also have a .153" initial compound leade length, the same as the SAAMI. Only difference I'm seeing on cursory inspection is the .2644" initial freebore dia. vs. .2645" on the drawing we have in Volume I, which is .0001".
Shilen makes great barrels. JP sells great finished barrels. JP does deep cryogenic stress relief on them, which many people feel is worthless, but then the JP barrels shoot, and hold groups very well under rapid fire, even from thin barrels, so I think JP knows what he's doing.
He's one of the few names in the industry who still competes, and has been competing in action-based precision matches for decades now.
NRA Basic, Pistol, Rifle, Shotgun, RSO
CCW, CQM, DM, Long Range Rifle Instructor
6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
www.AR15buildbox.com
CCW, CQM, DM, Long Range Rifle Instructor
6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
www.AR15buildbox.com