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I was going to calculate the recoil energy of my 870 using slugs with a "max dram" charge. the calculator asks for a number, so I'm not sure what to put in there.
Max dram?
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You can't, no max dram actually exists.Deerbuster said:
Dram is a unit of weight used to weigh ( :roll: ) blackpowder.
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I could swear I have seen some websites with slugs's recoil energy in footpounds that have max dram.... maybe the socalled dram equivalent could be calculated from the velocity? 1450 fps...
Oh yeah, I forgot to put in dram equivalent instead of dram. if theres a difference, then its what i meant.
Oh yeah, I forgot to put in dram equivalent instead of dram. if theres a difference, then its what i meant.
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According to physics, the momentum of a free recoiling firearm is equal and opposite in direction to the momentum of the ejecta and powder charge. The formula for free recoil of a firearm is:
Recoil Energy in ft. lbs. = (Bw Mv + 4700 Pw)2 / (64.348 Gw) where:
Gw= the weight of the gun in pounds
Bw = weight of the ejecta (shot and wad) in pounds
Pw = powder weight in pounds
Mv = muzzle velocity in feet per second
Example: Our shooter has an 8 lb. target gun with a load using 19.0 grs. of Clays, a wad weighing 33.0 gr., shot charge of 1 1/8 oz. and giving 1200 fps muzzle velocity. First we must convert the ejecta weight to lbs. (1 1/8 oz. = 492.0 gr.) Dividing grains by 7000 converts to pounds.
Gw = 8 lb.
Bw = (492.0 + 33.0)/7000 = 0.075 lb.
Pw = 18/7,000 = .003 lb.
Mv = 1200 fps
Substituting the numbers in the formula we find the recoil of the shooter's load = 21.05 ft. lbs.
(As published by Hodgdon, Lowry, et al.)
Recoil Energy in ft. lbs. = (Bw Mv + 4700 Pw)2 / (64.348 Gw) where:
Gw= the weight of the gun in pounds
Bw = weight of the ejecta (shot and wad) in pounds
Pw = powder weight in pounds
Mv = muzzle velocity in feet per second
Example: Our shooter has an 8 lb. target gun with a load using 19.0 grs. of Clays, a wad weighing 33.0 gr., shot charge of 1 1/8 oz. and giving 1200 fps muzzle velocity. First we must convert the ejecta weight to lbs. (1 1/8 oz. = 492.0 gr.) Dividing grains by 7000 converts to pounds.
Gw = 8 lb.
Bw = (492.0 + 33.0)/7000 = 0.075 lb.
Pw = 18/7,000 = .003 lb.
Mv = 1200 fps
Substituting the numbers in the formula we find the recoil of the shooter's load = 21.05 ft. lbs.
(As published by Hodgdon, Lowry, et al.)
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So the only way would be for me to open up a shell and get a powder scale and see for myself?
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Well like I said, its slugs, and its a one ounce slug, and I'll check out the box for any fine print.
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I can't find the weight of the powder anywhere. I checked all six sides of the Remington Copper Solid box.
I checked all six sides of the Remington Copper Solid box.
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Comparing your Remington load to a Ballistically equal Federal load, the dram Eq. of your load is 3.98. In short, that means the gun's going to kick a lot. So, basically, get used to it. The only way to know how hard it kicks is to step out on the back porch and pop one off :lol:
BT
BT
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Hm.... I wonder how legal it would be to do that. :lol: (i have neighbors)
And I've shot some before, just that I want some basis so I can know how much foot pounds I took to the shoulder
And I've shot some before, just that I want some basis so I can know how much foot pounds I took to the shoulder
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Not really. Calculated recoil is not important; felt recoil is what we all care about.Deerbuster said:
Pulling the trigger is the only way to experience that.
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You could look up a reloading recipe from Hodgdon.com to get a charge weight in grains for an equal load.... Thanks Randy for that example!
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The dram doctrine has gone on a long, long time; moreso with blackpowder and "volumetric equivalents":
http://www.chuckhawks.com/blackpowder_volumetric.htm Not all that fascinating, is it?
Okay, let's cut to to the chase.
For an 8 lb. gun, your load has approximately 28.7 ft. / lbs. of recoil energy.
http://www.chuckhawks.com/blackpowder_volumetric.htm Not all that fascinating, is it?
Okay, let's cut to to the chase.
For an 8 lb. gun, your load has approximately 28.7 ft. / lbs. of recoil energy.
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Thanks Randy,
I'll go see exactly how much this gun weighs at my mom's chiropractor (he's cool like that, he likes guns too). He has a medical scale thingy.
I'll go see exactly how much this gun weighs at my mom's chiropractor (he's cool like that, he likes guns too). He has a medical scale thingy.
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Point it at a deer and shoot it and you won't even notice the recoil. My deer rifle has a brutal kick at the rifle range but I didn't notice any kick at all taking an 8-point this afternoon.
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I've got a Remington 7600 in .30-06 that has a 18.5" barrel. I shoot a 180 Gr. load and it kicks a lot and it will ring your ears. I shot a deer with it last weekend and I didn't hear the blast or feel the kick, most amazing :lol:
BT
BT
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And I doubt that an 870 with slug barrel weighs 8 lbs to boot, so you could add a little more to that! Claybreaker nailed it! It only kicks if you miss the deer!
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The rifled barrel is only 20 inch with rifle sights. Its definately lighter than the vent rib smoothbore
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