Home Forums Hunting & Shooting Ask The Gunwriters Mule Deer's 9.3x62 data

For what it's worth, I started working with the 9.3x62 over a dozen years ago. The pressure limit for both CIP and SAAMI is very low, due to many old rifles in the cartridge, but I did some calculating with several formulas, comparing the powder room of the 9.3x62 with both the .35 Whelen and .375 H&H.

One difference, however, between the 9.3 and those two is a very long throat, common among cartridges of that era. Many early smokeless rounds (and the 9.3x62 was designed before the .375 and .35 Whelen) used heavy-for-caliber round-nosed bullets, hence the long throat, which tends to reduce peak pressures, especially with shorter, lighter spitzers.

Anyway, I calculated what sort of velocities the 9.3x62 would be capable of compared to the .35 Whelen and .375, taking into account powder room (it has somewhat more than the .35 Whelen) and bore diameter. Then I fooled with various newer powders until getting the calculated velocities. There were NO signs of excessive pressure, whether with 250 loaded to 2650 or so with RL-15 and Varget, or 286's at around 2500 with Big Game. (RL-17 wasn't around then, or I would have it tried it too.)

But to check my results, I also had Charlie Sisk test the loads with his Pressure Trace, using Norma factory ammo to adjust the results. (The PSI pressures from strain gauges are normally lower than with piezo equipment, the reason so many home-experimenters get such high velocities when "pressure testing." Many professionals use strain gauges, especially bullet companies, but they offset the results with piezo-tested "reference ammunition" from SAAMI.)

The results indicated the 9.3x62 handloads were in the 60,000 PSI range, which happens to be the SAAMI maximum average pressure for the .30-06.