.338 Edge Neck Tension Problem

[xXlojackXx]

Starting my load development for my new Benchmark built .338 Edge. I bought Defensive Edge's FL die set with the Redding .364 bushing. Here's where things get weird. With virgin RP 300 RUM brass, I follow Carlock's instructions and neck size the brass with the tapered expander and then remove the expander and just run the narrow cap on the depriming needle as I FL size the brass with the .364 bushing. Then load up my 300gr Berger OTM's and they shoot fine, actually they shoot amazing.

Then, when resizing the once fired brass (using the same process, seating the same bullets) the neck tension on a seated bullet is so loose that I can pull the bullet out by hand. Since the shot brass runs through the same bushing as the virgin brass, the OD of the neck is the same size, the only thing I can think is the brass of the neck is getting thinner and longer? But what can you do to remedy this problem so that the seated bullets will hold? Or do you not have this problem running better brass like Bertram?

The load it likes is as follows:

92gr H1000
Fed 215M
Berger 300gr OTM Tac @ 4.000" OAL
RP Brass

Please enlighten me with some wisdom of the problem.....?

 

[ChrisGarrett]

That's exactly what seems to be happening and really is the only answer.

.363" and smaller, might be in order.

No offense, but people like to complain about Lapua 338LM brass prices, as an argument for going 338RUM, Edge, BillyBob's 338 and whatnot, but it lasts a really long time compared to the usual RP stuff people use for the other carts and is less of a hassle to deal with, from what I've read.


Chris

 

[xXlojackXx]

Does anybody have experience with the Bertram brass?

 

[ChrisGarrett]

Does anybody have experience with the Bertram brass?

I don't, but if you have a ball mic, measure your 1x fired and sized necks in three places at 12:00, 4:00 and 8:00 and get an average for neck wall thickness.

You really need to know what those neck walls are micing at, otherwise you're just guessing.

If they're thinning out, they could be down to .013", for a total of .026". Add this .026" to a .338" caliber bullet and you get .364" for no neck tension/constriction.

You'll want a minimum of .002" constiction on the bullet for bolt guns which means that a .362" bushing should be in the ballpark.

If you're neck walls are .014" thick on average, that's .028", added to .338" for the bullet and you're at .366" without any tenision, so a .364" bushing would be appropriate.

If the .364" is letting the bullets fall in, or barely stay in, you'll need to go down in bushing size a bit more. .363", or .362", might be the ticket.

Chris