Does anybody have a recipe for the 168 gr BTHP or similar weight bullet? I have a box of these and thought maybe I would load them up for sillywet using the 7383. 2500 to 2600 fps would probably be fast enough if it shot well.

A friend of mine has told me that he's getting about 2350 FPS with 53 grains of 7383 under a 147 gr. FMJBT in the 30-06. That sounds slow to me, as Hi-Tech claims their lot is similar to 4064 or 4320 in burning rate, and it seems to be fairly true in my limited experience with it in the 22-250. 53 grains of 4064 ought to give that bullet something in the 2900-3000 FPS range, I'd think. He reported 100 FPS more with 10 grains less powder under the same bullet in .308. That seems odd, too. Perhaps his .308 load was more compressed, which might well make it burn faster. I'm getting ready to try it soon with 150 gr. SPs in 30-06, but haven't yet. 53 grains is an uncompressed case full to the mouth. You could probably shake it down and get as much as 54 in with some effort. It's pretty bulky. I think it's probably just a little slower than 4064 or 4320, but quite a bit faster than 4350. Probably hard to dangerously overload in medium capacity standard rifle calibers with medium weight bullets. There's a guy on the boards who blew up a Weatherby chambered for 7mm-300 Weatherby with it. Those big capacity magnums will certainly hold a lot more of it than they can safely handle.

IMR 7383 seems to act more 4064-ish in the smaller bores and up more towards 4381-ish in the grossly over-bore capacity larger cases. And you are right, these are the ones that can blow up on you because you CAN OVERLOAD THEM.

I intentionally pushed a 7mm Rem Mag with IMR 7383 up past the pale on one hot summer day until I expanded a primer pocket, then I backed it off to a safe level and loaded a hundred rounds at that safe maximum. These were within book speed ranges for the cartridge and are likely within book pressure ranges as well (I don't own a piezo-sensor equipped Ohler to be able to say for sure).

IMR 7383 will push large capacity cases up into their book speed ranges without going over pressure, you just have to start low and build up until you hit case head expansion pressure signs and then back off.

YOU CAN OVERLOAD THE BIG CASES, so you must determine a maximum load level and then stay safely below it.

IMR 7383 does seem to like those total coverage gas check bullets real well, now doesn't it?

Oldfeller