338 Rum to the Max !

The +p treatment eats out enough throat that I wouldn't do it period. If you want your throat half shot out, go shoot it out. rl33 is also a bit slow burning and bulky for a 338rum. I'm at a full case with my 300rums and 225's using rl33. I'd think a slow burning rather dense powder like lrt might be the ticket here. The new sta-ball hd? powder that's supposed to be ball/ retumbo might also be useful to you.
I disagree. The +P chamber design is a compromise that is all pluses.
I have done this for many years after studying Roy Weatherby's theories in throat length and pressure.
My first dabble in the 338 Edge was a disaster, neck was too tight, chamber wasn't tight enough and the only fix for me was the +P treatment after a set-back.

Now, how a longer throat works is that it doesn't allow a huge pressure spike, even when you are at or have slightly surpassed max pressure, and more often than not, this also allows higher velocity at lower pressure because the rise to max pressure is SMOOTHER.
Over the Pressure Trace II, it is easily seen that the long throat allows for a gentle start pressure and smooth rise to max. This allows more powder usage without the risk of a huge pressure spike. It is also an interesting fact that it causes certain powder that are erratic in other chamber designs to settle and actually be predictable across a set of tests…especially Winchester ball powders like 748 , 760 and 780. Others would most likely show similar characteristics.
Hope this makes sense.

Cheers.
 
Thanks !
Rl-33 is a powder I haven't tryed yet . I did end up with 2884 ft.per.sec in a 30" Carbon barreled 338 Rum with H-1000.
This one is a 1/9.4 26" Proof . If I can get it close to 3000 ft.per.sec or more I will be happy !
I'm going to talk to Shawn about his +p and then make a plan so far.
Thanks !

Rum Man
Try RL-33!
 
The most RL17 I have ever been able to load in a 338 Rum with a 160gr Barnes TTSX is 102gr which produced speeds of just over 4000 FPS
The 338 EDGE is 108gr wth the same powder and bullet produces 4200 FPS.
Just for comparison my buddy has a Rem 700P in 338 Lapua and that can hold 100gr of RL17 and a 160gr, still gets 4000 fps with 2gr less, my take is the steeper bottleneck makes up for less powder.
 
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