I'm using a Sinclair seating depth gauge to chase the lans on my Browning HCLR 300 WM. Followed the directions and triple checked my measurements and it determined I should seat my bullet to have a COAL around 3.530. Does this make sense since all reloading books say max COAL should be 3.340? Measured my magazine, and it can fit the longer round. Any thoughts would be appreciated.
COAL for Hell’s Canyon LR 300 WM
- Thread starter Brownsfan
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I own two HCLR and both measure 3.705 to the lands. Only that will hold you back is the magazine length. I dremeled all my mags out to hold these longer bullets. I load Berger 215 in the 300 Win Mags Coal 3.665 and Ogive 2.885. -0.040 off lands. You need to check OAL on all the bullets you use for the 300s.
The first part of the gauge instructions say to drop the bullet into the chamber point first and it will come to rest against the rifling....so I believe it is in contact with the rifling...is that synonymous with "the lands"?
Elkeater
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So get a fired case and then partially resize it. Like just enough that a bullet won't fall out but still can move. Then CAREFULLY insert the dummy round with the bullet seated way out into the chamber and close the bolt. Then CAREFULLY extract it and take the COAL. Do this several times till you get an accurate measurement.
For what its worth my HC long range .300 WM magazine accepts up to 3.600". My hand loads are 3.550".
For what its worth my HC long range .300 WM magazine accepts up to 3.600". My hand loads are 3.550".
