Using the same components in the same rifle how do you compare these two?

IOW Speer lists a maximum load of 56 grains of IMR 4350 for the Deep Curl 165 in the 30-06. COAL 3.160...These bullets require a generally lighter charge because of their construction.

Then what would be an equivalent H4350 load to this IMR4350 load??...If you can point me in the right direction I will work up a load since I have the Hodgdon version and a box of 165 grain Deep Curls.

All that is online

http://www.hodgdonreloading.com/

Hanco: where on line, other than the Speer website, which does not list H4350, would one find data for the 165gr DEEP CURL bullet in the 30/06??

I have found that the IMR powders are a little faster burning than the Hogdon powders. If you compare other bullets with those two powders (same bullet,those two powders) you should discover a trend.

The Deep Curls are said to have a slightly larger dia. that is why they call for a slightly lower charge.I've ran them just like any other bullet of the same weight and have never seen any issues.I would guess as long as your load is under the max for your rifle,you probably won't have any problems.

TreeMutt,

IMR4350 and H4350 average so similar that variations in manufacturing lots, or specific cartridge/bullet application, can switch burn-rate. Which is why over the years published loading data has sometimes shown H4350 slower than the IMR4350, and then a few years later the opposite.

Per usual, I would start a little low and work up, looking at both chronographed velocity and "pressure signs."

IMR-4350 is plain.

H-4350 has temperature stabilizing coating.

IMR-4451 has temperature stabilizing and anti Copper fouling coatings.