I also tried the Z-aim, and I'm probably one of the few people who didn't like it, might have been because my rifle is quite heavy but it certainly didn't feel secure for my use
I have one, very comfortable and easy to get the rifle off with practice, my stock has side mounted flush cups so my rifle is vertical while being carried, they spread the weight very well
For further information on the Armed Forces' interests in this area contact:
Commandant Wyke Regis Training Area, Camp Road, Wyke Regis, Weymouth, DT4 9HH.
Telephone: (01305) 831930
These maybe
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