Reddit reviews Ringside Boxing Training Heavy Duty Bag Spring (Up to 150-pounds)
We found 3 Reddit comments about Ringside Boxing Training Heavy Duty Bag Spring (Up to 150-pounds). Here are the top ones, ranked by their Reddit score.
This boxing heavy duty heavy bag spring can hold bags as heavy as 150 poundsMade of all steel construction this heavybag hanger spring is extra strongSpring will lesson the shock of hard hits, kicks and knees to preserve the longevity of your bag mountsPerfect for boxing, MMA, Muay Thai, or any of your favorite contact sport heavy bag training
Since your mounting is going to be less than ideal for a heavy bag, I strongly recommend getting a spring and don't just hang it with chains.
This is what I bought: http://www.amazon.com/Ringside--Poundheavy-Duty-Heavy-Spring/dp/B006K408LG/
Initially I had my bag hanging in the garage with just chain but was sort of worried by the shock traveling up. I bought that spring and put it in and it does a really good job of absorbing some of it. Initially I bought some springs that are used for patio swinging benches, since I saw some people talking about using those online for their bags, but those are rated far too high (like 300 lbs) and thus don't absorb enough imo.
If you need a picture of it installed, I can provide.
Ringside Steel I-Beam Heavy Bag Hanger https://www.amazon.com/dp/B000NZIXBU/ref=cm_sw_r_other_apa_nQtwxb3885VE9
Ringside Heavy Duty Bag Spring https://www.amazon.com/dp/B006K408LG/ref=cm_sw_r_other_apa_uRtwxbH3TC0W8
Or
http://m.homedepot.com/p/Everbilt-352-lb-Capacity-Heavy-Duty-Porch-Swing-Spring-SP-9649/100193571
I use the home depot swing on wooden joists in my basement and there's no vibration at all, that setup would be fine. Maybe add a small length of chain if you have to drop it down
I use a heavy bag spring between the bag and the ceiling hanger (I use the same ceiling hanger, screwed into the ceiling studs with lag bolts). The spring doesn't eliminate the noise, but it's certainly easier on the studs. Note: you may have to get a different spring, since your heavy bag is 70 pounds and the one I linked to is specifically for 150 pound bags.
EDIT: Here are a variety of springs for different weight bags.