I'm experimenting with the Barnes 300 grain TSX and Banded solids in my 375 H&H using H4350.

Most people I see are shooting 77-78 (or more) grains of H4350 with 300 grain bullets. I have shot 72-74 grains in mine with no sign of pressure and relatively mild recoil. I notice that 75 grains of H4350 fill the case to the bottom of the neck and the Barnes TSX is so long that seated to the correct depth it compresses the load by about 1/2 inch.

I figure as I work up to 77-78 grains of powder this is going to put a lot of compression on the powder, so my question is;

How much is too much, powder compression?

I believe the general rule is if the bullet doesn`t move over a couple days from the pressure of the powder on it the load is probably OK.
I personally don`t like to compress that much, and if I start to fill the case neck itself with a bullet that seats below the neck/shoulder junction I switch powders.

Try settling powder with vibration off of: eletric tooth brush, elec shaver, or elec back massage.
I have a elec back massage that I put on my hand and just pick up tray of rounds and hold and powder settles down around 1/4 to 1/2 inch.
I don't like to hear the powder crushing also.

years ag o when we had to use .250-3000 cases to form 22-250s I was compressing IMR 4350 and 4831 starting at the top of the neck. Never ran into a problem and it was accurate.

Today with a number of cases we have arrived at the same scenario using accurate data 86. So far everyone doing it is giving the powder load acclaim. BALL POWDERS ARE SOMETHING ELSE . I've driven primers out trying to compress it. roger

you can't compress too much.....almost....
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