6.5 Grendel TC Contender

[JASmith]

Several techniques exist for optimizing one's OAL. Here is what I use:

• Start out by finding the OAL where your ogive first touches the lands.
  
  
• Then, back off by the Barnes recommended amount.
  
  
• Do an OAL ladder using a slightly reduced from max load. Run the OAL in increments of .005" to .010" from that recommended .050" down to touch to determine the most accurate OAL. The reduced load is suggested because getting close to or actually touching the lands causes an increase in pressure of a few thousand psi.
  
  
• Repeat with five five-shot groups with OALs .006", .003', 0.00', -.003' and -.006" from your best OAL in the first pass.
  

If your SSK barrel was cut with a SAAMI-compliant reamer, the 0.50 degree taper where the freebore normally would be broadens the sweet spot for best accuracy and at the same time makes getting the precises land-touch OAL more interesting.

I normally run the powder charge weight optimization after I am happy with the OAL.