Attachment 0014 RECOMMENDATION FOR CHARGE ESTABLISHMENT AND UNIFORMITY CALCULATIONS.pdf

Recommendation for Charge Establishment & Uniformity Calculations

1. CHARGE ESTABLISHMENT PHASE

METHOD 1.

The linear relationship between the corrected velocity values and the charge weight is defined by the following formula:

V = mC + B where: V = target velocity m = slope of the line B = y-intercept of the line

C = charge weight

Use the following formulas to calculate the slope and intercept of the least square line:

i i i i i i i ii i i ccn vcvcn m n cmv B i i i i where: n = total number of samples ci = charge weight for ith vI = observed velocity for ith round

METHOD 2.

Use Excel XY Scatter chart (do not use a line chart): Charge weights as X-values, Velocities as the Y-values, include a trend line, include equation and R2 (trend line options).

Calculate the charge weight by solving for C:

C = (Vp - B)/m where: Vp = prescribed (target) velocity m = slope of the line B = y-intercept of the line

C = charge weight

Attachment 0014

2. UNIFORMITY PHASE CALCULATIONS

After velocity corrections are determined, Calculate the final recommended charge weight using the following formulas:

m

VV

DC UP −=

and

DCCFRC +=

It follows from these two equations that m

VV

CF UP

RC

where: C = charge weight from uniformity DC = amount of propellant adjustment required FRC = final recommended charge weight m = velocity slope from charge establishment VP = prescribed velocity VU = corrected mean velocity

It follows from these two equations that