Got got back from the range today. Shot about 150 9mm rounds out of my Kel-tec sub 2000 and 75 out of my Ruger AR15. I had no problems either rifle, and they have the $16.00 Amazon bi-pods. The Kel-tec bipod did loosen a little, 1/4 turn of the adjusting know took care of that. So far I am pleased 100% with both bi-pods.