just a helpfull thing for calculating recoil, ext.

m-134

m-134

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this works best if you have a scientific calculator since you type it almost exacly as it shows.

Free Recoil Energy
(W1 x Vp + 4700 x W2)√
---------------------------
64.348 x Wg

W1= weight of bullet in pounds. (grains divided by 7000=pounds)
W2= weight of powder charge in ounds.
Wg= weight of gun in pounds.
Vp= muzzle velocity of bullet in FPS.

example.
(.021 x 2700 + 4700 x .007)√ = (56.7 + 32.9)√ = 8028.16 ÷ 579.132 = 13.86 ft-lbs of recoil.
64.348 x 9 = 579.132




Bullet Impact Energy In Foot-pounds
bullet weight in grains x velocity√ ÷ 450400 = ft-lbs of energy.

Example. 150(grain bullet) X 2700(FPS)√2 ÷ 450400 = 2428 ft-lbs of energy.


Sectional Density
a bullets weight in pounds divided by the square of its diameter in inches.
W= bullet tip weight
D= bullet tip diameter
W ÷ 7000 ÷ D√2 = .226

Example.
150(grain bullet) ÷ 7000 ÷ .308(tip diameter) √2 = .226


Sight Correction
this formula will show how much change in inches will be needed to correctly zero in your sights.


M = (D ÷ R) x S.


M= movement in inches needed to zero in sights.
D= impact deviation of bullet in inches.
R= range in inches.
S= sight radius. (distance between sights)

example: firearm is hitting 6" low at 50 yards.

D= 6", R= 50(yards) x 36 = 1800", S= 20"

6 ÷ 1800 x 20 = M= .067"

alloy - lead - tin percent - antimony - BHN
monotype - 72 - 9 - 19 - 28
stereotype - 80 - 6 - 14 - 23
linotype - 84 - 4 - 12 - 22
lyman no2* - 90 - 5 - 5 - 15
taracorp magnum* - 92 - 2 - 6 - 15
1 to 1 lead/lino - 92 - 2 - 6 - 15
electrotype - 94.5 - 3 - 2.5 - 12
10 to 1 mix - 91 - 9 - 0 - 11.5
16 to 1 mix - 94 - 6 - 0 - 11
20 to 1 mix - 95 - 5 - 0 - 10
30 to 1 mix - 97 - 3 - 0 - 9
wheelweight* - 95.2 - 0.5 - 4 - 9
40 to 1 mix - 97.5 - 2.5 - 0 - 8.5
pure lead - 100 - 0 - 0 - 5
*= responds well to heat-treatment.
 
Last edited:
Holy ####, I'll need a diaper and a helmet to do these.

I hope this isn't a test.

:D :D

Great info all in one place. I will have to print these out as the Sectional Density comes in handy in quickload.
 
This is almost enough to get more people to use the memory on their calculator rather than writing down a number, entering another, writing down another, and so on. Google "recoil calculator" and a veritable cornucopia of online recoil calculators comes up. But for when the inernet is down or your connection is gone, enter these in excel, and you can gang formulas in excel too, saving entering answers over and over to the next step.
 
m-134 said:
Free Recoil Energy
(W1 x Vp + 4700 x W2)√2
---------------------------
64.348 x Wg

W1= weight of bullet in pounds. (grains divided by 7000=pounds)
W2= weight of powder charge in ounds.
Wg= weight of gun in pounds.
Vp= muzzle velocity of bullet in FPS.

example.
(.021 x 2700 + 4700 x .007)√2 = (56.7 + 32.9)√2
64.348 x 9 = 579.132 = 13.86 ft-lbs of recoil.


allow - lead - tin percent - antimony - BHN
Click to expand...

Sorry, brother but you may need to edit your recoil formula. Nice of you to post it but I certainly can't make it work, even your example is not possible to calculate. You may be missing an operations sign. Where do you go from the SQRT to the next line. Any time I see a formula with one statement on top, a line, then another statement below, that means to divide the top statement by the bottom statement. Your example has nothing about that and the numbers are not possible from that, or ... am I just an idiot? Please explain as you would to a child, high algebra and force calculations were more than 30yrs ago.

Also, I think you meant ALLOY, not ALLOW in your metal compositions. Dang spellcheck!! I spend more time correcting auto-correct, than I do typing when I use my IPad.

Oh, and thanks for helping out... I had forgotten the formula for recoil.
 
thanks, i corrected it now.

rookie wildcat said:
Sorry, brother but you may need to edit your recoil formula. Nice of you to post it but I certainly can't make it work, even your example is not possible to calculate. You may be missing an operations sign. Where do you go from the SQRT to the next line. Any time I see a formula with one statement on top, a line, then another statement below, that means to divide the top statement by the bottom statement. Your example has nothing about that and the numbers are not possible from that, or ... am I just an idiot? Please explain as you would to a child, high algebra and force calculations were more than 30yrs ago.

Also, I think you meant ALLOY, not ALLOW in your metal compositions. Dang spellcheck!! I spend more time correcting auto-correct, than I do typing when I use my IPad.

Oh, and thanks for helping out... I had forgotten the formula for recoil.
Click to expand...
 
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