Advantages to finding seating depth before charge weight?

[Winny94]

This is a good plan for a cartridge without much info. What powder do you plan on testing with? Also what bullet?

H1000 and the 7mm 180gr VLD Hunting. I don't need sub .5moa accuracy. I'd be very happy w/ .5-.75 and a decent SD. It's a hunting round, not a match round.

 

[Ringostar]

For a target rifle, I like to take known good loads and back off slightly and test seating. Then slowly work up on powder at the preferred seating depth. Since it’s for hunting I assume that it needs to feed from a magazine. Compare bullet touch to lands measurement vs max magazine length. Make sure that you still have clearance at max mag length. I’m not saying this is perfect, but personally I wouldn’t want to shoot a jammed load in a hunting rifle. In you need to extract a loaded round, you could get a chamber and trigger full of powder. If you still have bullet clearance at max mag length. Then I would try a rough powder test at that length with this cartridge, since there won’t be book data for it. You should be able to find a charge weight where pressure starts to show issues. Back off from your max charge area and then start testing seating depth that feeds from your magazine. I’ve never tried the .040 change that Berger recommends. I would probably go .020 change for a rough test. When you find an area with promise, then test finer jumps in that area. Then do a finer charge test. It might sound like a lot of work, but when you decided to go with a wildcat round you didn’t plan on getting by easy. I actually like the info that I’ve read about this cartridge, good luck!

 

[Murray Brook]

Still reading, but if I had to do it today, id probably load 8ish rounds in .5gr increments from 57-61ish just to make sure pressure is safe, then pick a middle charge weight (58-59), and then run Bergers depth test. But im hoping I get a few more opinions before having to load this next batch.

This is just what I do, and it works for me. Don't be afraid to test as far as .120 off lands. My 7mm/08, which I thought was a .7 rifle became a .4 rifle when I decided to try the Berger depth test and found that .120 off was my best depth. JME

 

[dsculley]

I am using the 168 gr VLD's. The charge weight for my seating depth test is usually 5% below published max. The main consideration is I want a safe load, but one not too far from the range I expect to be using after load testing. You could drop back to 7% below max. The main thing is to know you are at a safe load for testing seating depth.