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anyducks · July 19, 2010, 10:43 PM

I am working on some Power Factor (pf) loads and wondering if there is a valid relation ship between pf and recoil spring tension in lb.

The following are constants (I believe)
Gun weight, barrel, primer, case, and bullet weight (grains),

variables
powder charge
bullet velocity (FPS)

prediction
equillivent slide action (ejection of case)
recoil spring lb need to operate the slide

125 grain
1100 fps
PF constant 1000

grains x fps / PF constant 1000 = PF
125 1100 / 1000 = 135.5

recoil spring resistance lb = rs lb
18.5 lb

pf / rs lb = pf / rs lb cofiecent
135.5 / 18.5 = .135

at this point the slide reliably ejects the spent case and loads the next round.

Changing fps to 900 the pf drops to 112.5 (expected).
Presuming the ps / rs lb is valid then a recoil spring of 15 lb would produce .133 (ps /rs lb) and similiar reliability?

July 19, 2010, 10:43 PM	#1
anyducks Junior Member Join Date: May 28, 2007 Location: Vancouver, WA Posts: 3	Power Factor vs Recoil spring lb I am working on some Power Factor (pf) loads and wondering if there is a valid relation ship between pf and recoil spring tension in lb. The following are constants (I believe) Gun weight, barrel, primer, case, and bullet weight (grains), variables powder charge bullet velocity (FPS) prediction equillivent slide action (ejection of case) recoil spring lb need to operate the slide 125 grain 1100 fps PF constant 1000 grains x fps / PF constant 1000 = PF 125 1100 / 1000 = 135.5 recoil spring resistance lb = rs lb 18.5 lb pf / rs lb = pf / rs lb cofiecent 135.5 / 18.5 = .135 at this point the slide reliably ejects the spent case and loads the next round. Changing fps to 900 the pf drops to 112.5 (expected). Presuming the ps / rs lb is valid then a recoil spring of 15 lb would produce .133 (ps /rs lb) and similiar reliability?