Shot Bag Question

[newfiebackflip]

I was curious if anyone has made a "shot bag" or "sand bag" for metal forming before?

I would just like to know what would be the best type of leather to handle the constant pounding and punishment that comes from the hammer and metal. For the most part, the ones that I have seen on the internet are made out of cowhide (thats what they label it as on their sites) but could latigo or veg-tan bends work? The average thickness that I have seen is 3-4 oz.

Should something like these bags be sewn with a machine or would hand stitch work just fine (double stitched of course)

Any info is good info unless its try google.

Thanks for looking and your input.

[Scary Leatherworks]

my brother-in-laws is made of suede. filled with very fine sand