load data figures

Crankgrinder · August 17, 2011, 07:21 PM

some of my data lists "pressure factor" in the form of a decimal ".9353" and so on which can be used to determine aprox. pressures for reduced loads assuming the pressures listed are for the maximum safe loads in each table. can these"pressure factors" or "velocity factors" as some have called it be determined for loads that do not list such? and if so how?

WIL TERRY · August 18, 2011, 10:46 AM

WHAT load data shows this ??

**Unclenick** · August 18, 2011, 11:12 AM

The 1 grain velocity/pressure factor is Richard Lee's concept, and he gives it in his book (at least, it's in the 2nd edition) for which he had the opportunity to measure it for some bullet and chambering and powder combinations. Obviously he didn't have the opportunity to do it for everything.

I don't know any other source of that number. You may be able to deduce it from published pressure and velocity data. I haven't paid close enough attention to it to try. I use QuickLOAD and a chronograph to get a good match between it and my components, then let it predict the pressures for load changes. Usually works pretty well.

August 17, 2011, 07:21 PM	#1
Crankgrinder Senior Member Join Date: July 24, 2011 Location: Texas Posts: 917	load data figures some of my data lists "pressure factor" in the form of a decimal ".9353" and so on which can be used to determine aprox. pressures for reduced loads assuming the pressures listed are for the maximum safe loads in each table. can these"pressure factors" or "velocity factors" as some have called it be determined for loads that do not list such? and if so how?

August 18, 2011, 11:12 AM	#3
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,061	The 1 grain velocity/pressure factor is Richard Lee's concept, and he gives it in his book (at least, it's in the 2nd edition) for which he had the opportunity to measure it for some bullet and chambering and powder combinations. Obviously he didn't have the opportunity to do it for everything. I don't know any other source of that number. You may be able to deduce it from published pressure and velocity data. I haven't paid close enough attention to it to try. I use QuickLOAD and a chronograph to get a good match between it and my components, then let it predict the pressures for load changes. Usually works pretty well. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

August 18, 2011, 10:46 AM	#2
WIL TERRY Senior Member Join Date: July 6, 2000 Location: BLACK HILLS Posts: 1,322	WHAT load data shows this ??