Optimal Charge Weight

[DeadElephant]

If you use the OCW process to determine an accuracy node will the node change if you change brakes or suppressor. The poi may shift but wasn't sure if it would impact the OCW or not.

[Tim K]

Interesting question. I don't know the answer, but I'd speculate that any muzzle device would change barrel harmonics and screw up your node.

[DeadElephant]

I've read Chris Longs papers and research and wasn't able to determine a specific answer either way. I'm going to shoot an email over to Dan Newberry and see what he says.

[Tim K]

Post up what you learn.

[DeadElephant]

This was Dan's response:
"No, the OCW should remain the same. A slight seating depth tweak will often restore any apparent lost accuracy.
Dan"

[Tim K]

Interesting and surprising. Thanks for the update.

[BigBear]

Derail: From the thread title I was like "It depends on the mass of what you're trying to blow up"... HAHAHAHA.

[bkincaid]

My experience the last few weekends say it makes quite a bit of difference.

I've been doing ocw with my new Ruger PR in .243 Winchester with a TBAC 30-P1 installed using Hybrid 100V, Berger 100 grain and 105 A-max, Winchester brass and federal 210 primers.

I found a few nodes with both bullets with can on. Just for grins I shot those same loads after removing the can and the nodes are gone with both bullets, YMMV.

eta I did not change seating depth to see if it would change anything.

[longrange2]

I developed a good load for my 6.5 creedmoor using the OCW method and 142 grain Sierras. Shoots the same tiny groups with can on or off, TBAC 30CB7. The rifle has a remington varmint type contour.

[DeadElephant]

I've seen considerable accuracy changes from moving between suppressed and unsuppressed on several of my loads. I have to admit though that I did not follow OCW process exactly as Dan specifies. I may work with him directly and see if I get different results.