It’s a matter of calculable physics. No…it won’t matter much in a perceptible way. The recoil is likely from the muzzle blast. I doubt the valve “recoil “even amounts to 1/2 fpe.
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Skout Skout Epoch Share and Discussion
- Thread starter Lewis
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Inertia v setback is mechanical mass in motion in nature and math is calculable but recoil created by air escaping the muzzle is? Research required… come on physics peeps jump in.@thomasair
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what drove your caliber choice?Picking up mine TODAY ....
95% of my airgunning is suburbia backyard piddlin, or FT related so i chose the .177 = I don't think there are many of these tiny tots in play yet.
Of note, on my caliber choice, I Ran into some magazine feed issues; but Skout is "on it" and in just two days they are already sending two new magazines for me to try.
I think some airgunners, like me, are like damn gerbils ... next shiny thing catches their eye.
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Given a hammer of say 20 grams, sprung on say a 10 lb spring with .7" of hammer travel, (arbitrarily chosen), you get the following
Hammer Velocity : 25 fps
Hammer Locktime : 3.8 ms
Hammer FPE : .429
Most pcps will operate with less than 1/2 FPE being transferred from the hammer to valve as thomasair already stated. Some with as little as .1 FPE.
The majority of any airguns recoil is the weight of your projectile and the air behind it traveling down the barrel, believe it or not generally most guns operating at or near their plateau shoot a mass of air between 50%-100% of their projectile's mass, depending on various factors from pellet weight/sectional density to energy output.
Also its not just air escaping the muzzle, or the pellet, say you had a really, really long barrel...so long that the pressure gradient left the muzzle pressure equal to atmospheric, would this gun exhibit any recoil, even at very high energy levels? Of course it would...
-Matt
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Can't wait to hear more about the .177! I'll be looking for a barrel kit as soon as they are available.
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You can probably simplify recoil on the energy blast by the dwell of the pellet inside the barrel. A short barrel making 60 fpe with 1 ms dwell will have a 1ms long recoil @ that energy, a barrel with 4 ms dwell will have the recoil last for 4 ms @ that energy.
How to convert the above to momentum...
Lets say the above was done with a 33.95 grain pellet @ 880 fps.
Momentum = mass × velocity
33.9 grains × 0.00006479891 pounds/grain ≈ 0.0021947 pounds
Momentum ≈ 0.0021947 pounds × 880 fps ≈ 1.93304 pound-feet per second (lb-ft/s)
Inertia is...
Inertia = mass × velocity^2
Inertia ≈ 1703.41 pound-feet squared per second squared (lb-ft^2/s^2)
So your exposure to the above inertia that is felt, is based on the exposure time (dwell time) of the pellet in the barrel.
-Matt
How to convert the above to momentum...
Lets say the above was done with a 33.95 grain pellet @ 880 fps.
Momentum = mass × velocity
33.9 grains × 0.00006479891 pounds/grain ≈ 0.0021947 pounds
Momentum ≈ 0.0021947 pounds × 880 fps ≈ 1.93304 pound-feet per second (lb-ft/s)
Inertia is...
Inertia = mass × velocity^2
Inertia ≈ 1703.41 pound-feet squared per second squared (lb-ft^2/s^2)
So your exposure to the above inertia that is felt, is based on the exposure time (dwell time) of the pellet in the barrel.
-Matt
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VERY Nice !!!
Not shot the EPOCH in a couple months ... really no need for .30 and unwilling to shell out the $$$ in cost for giggles plinking .. so we wait
Not shot the EPOCH in a couple months ... really no need for .30 and unwilling to shell out the $$$ in cost for giggles plinking .. so we wait
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Well, I actually had a prototype.22 in my hands at Skout, so hopefully it proves out and they become available soon.VERY Nice !!!
Not shot the EPOCH in a couple months ... really no need for .30 and unwilling to shell out the $$$ in cost for giggles plinking .. so we wait
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Scotty,
Is that the Skout liner or another barrel?
Very impressive. I always have one hole groups...... until the second shot!
Is that the Skout liner or another barrel?
Very impressive. I always have one hole groups...... until the second shot!
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That is the Skout standard liner. I fully expected the fifth shot to be a spoiler, but it magically went in the same hole! I know five shots doesn’t represent a whole lot, but it makes me happy anyway.
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In summary, Newtons third law, every action has an equal and opposite reaction, longer barrel means you feel that much longer lol. (especially at lower pressures that slowly build up the speed vs higher pressure that has a sharper build up and even less dwell)
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That’s not how that works at all.
A 20 fpe gun with a 30” barrel will have much less felt recoil than a 20fpe gun with a 4” barrel. This is simply due to the greater secondary recoil from the muzzle blast. The primary recoil will be the same. Getting a pellet up to a particular speed in a shorter barrel will create more secondary recoil than a long one.
As a person that makes some 13” barreled 20fpe guns and 24” barreled 20fpe guns….this is not something that can be contested by numbers. It’s readily obvious to anyone that shoots them both.
Mike
A 20 fpe gun with a 30” barrel will have much less felt recoil than a 20fpe gun with a 4” barrel. This is simply due to the greater secondary recoil from the muzzle blast. The primary recoil will be the same. Getting a pellet up to a particular speed in a shorter barrel will create more secondary recoil than a long one.
As a person that makes some 13” barreled 20fpe guns and 24” barreled 20fpe guns….this is not something that can be contested by numbers. It’s readily obvious to anyone that shoots them both.
Mike
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That is not what I stated, and you're taking it out of context, do the math...I said longer, not stronger...
You know what sharper means right, too? I was also specific about this in the post..
Also I never stated at equal energy, clearly if you go longer barrel you typically go for more energy...and if in the SKOUTS case as this discussion IS, its LOW pressure in a LONG barrel...
-Matt
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Feeling longer results in less felt recoil. It’s the very principle that makes recoil absorption devices in artillery function. Spread the recoil over a longer time and it feels less.
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You need more air mass to make 20 fpe in a 4" barrel than a 20" or any longer length barrel as well. That contributes so much to recoil, yet you fail to mention it...unfair comparison
Not sure who you're arguing with? Cause it isn't me but you're barking up my tree....you interpret longer and sharper as you want because you're in another ball park than me...
Also explain to the chaps why this gun has more recoil than they are accustom to?
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