Ragnarok wrote:Ah. You've made a bit of a boo boo here....
Thanks for the heads up... something didnt seem right in my head and I neglected to pull out my manuals from physics to reference. Spring equations should be ingrained in my head pretty solid after Diff EQ lol...
I'll redo that part and find the appropriate gas springs!
And a few days later.... I've finally found my method of absorbing the recoil.
First off - screw springs - If I were to stick with a 6 inch spring for this project it would need to be beastly. If I were to use a gas spring for it - it would be so harsh on the return stroke (unless it had amazing dampening... hmmmm)
So after some thorough research in the field of dampening gun recoil - I came across some stuff used by high powered rifles. "industrial shock absorbers" - go figure... i forgot the word industrial in all my previous searches...
Case in point, Using conservation of momentum, I found that my gun would recoil with a maximum velocity of something like 38 ft/s shooting a 1 lb projectile at 880f/s (yes, right around 10K lb ft of muzzle energy). My gun will weight about 25lbs with the sled (now 8020 material).
Using the mass and velocity of just the gun recoiling, I can get the kinetic energy (don't forget to divide weight by gravity!) and so I found I need to look for a shock, or shocks that give me a ceiling value of 7000 in lbs of energy absorption - conveniently that is how shocks are rated in the industrial field - by the total amount of energy they can absorb (within realistic shaft speed values) per compression.
Low and behold I found 2 shocks on ebay that have a 2" stroke and absorb a cumulative 9200 in lbs of energy. They also have adjustable dampening rates (nice for shooting lighter ammo).
And that brings me to the most current version of my design... meh when will I get this thing done? lol.
I'm going to use a section of 40series 8020 material and their respective linear bearing system for the recoil sled for the chamber. Onto this the gun will bolt, and the boss's for the recoil absorbers.