Here's a video of me measuring the MAX COAL of a 120gr Nosler BT in my Grendel II AR Stoner barrel. Midwayusa, and Brownells have switched to Grendel II's. They both switched to the Grendel II out of safety concerns over the compound throat. You can also get Grendel II's from Underground Tactical and Maxim Firearms and of course Satern barrels.
Here's some max COAL of various bullets. If its over about 2.305 the bullet will need to tolerate a jump. The 123gr AMAX and 123gr SST both like the jump. If it's 2.305 or under the bullet can be loaded to just of the lands. The reason that the compound throat was chosen is that the 108/123gr Scenar which was decided was critical for target shooting and military adoption back in 2005 was not jump tolerant. So they choose the lother walter compound throat. It allowed the 108/123gr scenar to be loaded to within .005 of the lands and produced good accuracy that of course crippled the shorter nose spitzer hunting bullets. The 123gr SST does well in the compound throat which is why 95% of Grendel Hunters use it and not the rest of the 6.5mm hunting bullet line up. Those Internet PR guys for AA (its obvious who they are isn't it) are going to earn there pay checks in the coming months attacking the Grendel II. They don't have facts so they'll just make personnel attacks and attempt to derail discussions. I hope the SAAMI Grendel guys don't try to get the same velocities and blow up there guns yikes!!
Grendel II max COAL (AR Stoner Grendel II)
95gr Hornady Vmax COAL= 2.275
100gr Nosler Partition COAL=2.266
100gr Nosler BT COAL= 2.306
120gr Hornady Amax COAL= 2.257
120gr Nosler BT COAL= 2.307
120gr Barnes TTSX COAL=2.330
120gr Barnes TSX COAL=2.295
123gr Hornady SST COAL=2.342
123gr Nosler CC COAL=2.285
129gr SP Interlock COAL=2.275
129gr Hornady SST COAL=2.360
140 Nosler BT COAL= 2.32
140gr Nosler Partition COAL=2.303
Here's some max COAL of various bullets. If its over about 2.305 the bullet will need to tolerate a jump. The 123gr AMAX and 123gr SST both like the jump. If it's 2.305 or under the bullet can be loaded to just of the lands. The reason that the compound throat was chosen is that the 108/123gr Scenar which was decided was critical for target shooting and military adoption back in 2005 was not jump tolerant. So they choose the lother walter compound throat. It allowed the 108/123gr scenar to be loaded to within .005 of the lands and produced good accuracy that of course crippled the shorter nose spitzer hunting bullets. The 123gr SST does well in the compound throat which is why 95% of Grendel Hunters use it and not the rest of the 6.5mm hunting bullet line up. Those Internet PR guys for AA (its obvious who they are isn't it) are going to earn there pay checks in the coming months attacking the Grendel II. They don't have facts so they'll just make personnel attacks and attempt to derail discussions. I hope the SAAMI Grendel guys don't try to get the same velocities and blow up there guns yikes!!
Grendel II max COAL (AR Stoner Grendel II)
95gr Hornady Vmax COAL= 2.275
100gr Nosler Partition COAL=2.266
100gr Nosler BT COAL= 2.306
120gr Hornady Amax COAL= 2.257
120gr Nosler BT COAL= 2.307
120gr Barnes TTSX COAL=2.330
120gr Barnes TSX COAL=2.295
123gr Hornady SST COAL=2.342
123gr Nosler CC COAL=2.285
129gr SP Interlock COAL=2.275
129gr Hornady SST COAL=2.360
140 Nosler BT COAL= 2.32
140gr Nosler Partition COAL=2.303
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