Anybody make a throat erosion gauge for AR15 based 6.5 Grendel.

[usmcm16a2]

Folks,



Does anyone know of a manufacturer of a throat erosion gauge for a AR15 based 6.5 Grendel. A2

[Bwild97]

You can use the Hornady OAL gauge to track erosion!

I use the straight gauge.

[usmcm16a2]

Bwild,


How, I used to the Garand/03 gauges. Enlighten me. A2

[LRRPF52]

If you're seeing throat erosion with a cartridge that operates at ~50,000psi working pressure, I'd be interested to see some quantifiable measurements before and at different round counts.

I haven't seen anything like this with my 16" barrel that I've had since 2009. Les Baer has a barrel they claim is shooting sub-1/2 MOA after 20,000rds.

[Bwild97]

With the Hornady AOL gauge you will need the modified case for the chamber you wish to track, pick a projectile any projectile, lable it or mark it so that it will be identified as the one you will use the every time you want to check for erosion. Keep a log and record the measurement every time you measure.

You can also use the RCBS OAL gauge, the nice thing about this gauge is that comes with an arbitrarily shaped projectile that can not be misplaced.

But as LRRPF52 mentioned "Throat Erosion" in the 6.5 Grendel is basically an oxymoron.

[LRRPF52]

If we were talking about .260 Remington and 6.5x284, I would just prefer to bore scope anyway, along with JB paste on a patch on a brass brush on a rod on a drill to touch up the throat on occasion.

The cartridges that generate working pressures over 58,000psi and into the 60,000+ range need to be watched more carefully, especially as the over-bore increases, like 6.5x284, .264 Win Mag, or the 26 Nosler.

I think the American Rifleman article with the 26 Nosler saw throat erosion within 100rds.

[Klem]

The Stoney Point/Hornady gauge will do this. I have done this with F-Class barrels. Set aside a projectile and keep this with the gauge (must be exactly the same projectile used over the barrels' lifetime). Don't put too much forward pressure on the soft copper bullet when taking readings to avoid deforming the bullet.

If you want a fixed jump-to-lands then you will be chasing the throat as it wears to the point your re-loads will no longer fit in the mag. All barrels wear at the throat where the pressure is concentrated. That said, 52' is correct, throat erosion may not affect accuracy given you can chase the lands for a period of time.