What bb's did you use for this test?
I didn't see that posted, I understand why the pdi .01 got such bad results. g&g bios why?good to know you followed what was posted
" The BBs used are G&G .20 BIO BBs."
from the link to the original.
for any others unable to check
ARMS October Custom Inner Barrel testing
AEG Custom Inner Barrel Testing As one of the principally used upgrade parts, inner barrels are used to increase velocity and influence the BBs final flight path. Currently, both tight and loose barrel options exist when used to tune consistency and airflow. The recently developed loose barrels use the air released at the time of firing to stabilize the round and keep contact between the BB and barrel to a minimum, which have their roots in the Hop Twist barrel developed by Tanio Koba. Utilizing rifled channels cut into the barrel to guide the airflow down the barrel to a high degree of precision, this results in some of the best results among many of the commercially available loose barrels. Conversely, there also exist tight bore barrels that minimize the contact with the inner barrel by adding velocity to the BB. KM head has also produced a barrel that fits into both categories, however there are many factors in installing this barrel that we were not able to replicate for the sake of the test. Inner barrel testing process: The gun used is a TM Recoil Shock M4A1 Carbine. The barrel length is the stock M4 carbine length, or as close as possible The BBs used are G&G .20 BIO BBs. A short zoom scope was used to help minimize the human factor. A standard Marui hop was used. The hop was first adjusted to zero the scope, and when barrels were changed, the hop was adjusted to meet the zero on the scope, without changing any elevation settings on the scope itself. Velocity was measured after the hop setting was completed on each barrel. The targets were a paper target at 20 meters, and a 20cm diameter metal plate at 30 meters. The groupings were measured on the paper target, and the metal plate was used to record the number of positive hits, and 10 rounds were fired at each distance.