During WWII, the M1 Garand was issued with a leather sling. Later, 1962 Fort Knox, the M1 I was issued, (serial number 1603418), had a web "carrying strap". When I entered Service Rifle competition, I found out the difference. The leather sling is an aid to target shooting. The web carrying strap is only used for carrying the rifle at, "Sling Arms", while marching...we shot "train fire" (silhouettes pop up at random distances), and were never taught to use a sling as in "known distance" target practice. Get an experienced competition shooter to show you how to get into the sling and how it is adjusted and used. You might luck-out and find some pictures or diagrams on-line to show and explain how it is done.
Sometimes you get what you pay for, sometimes you only pay more for what you get.
Three shots are not a "group"...they are a "few".
If the Bible is the literal, infallible, unerring word of God...where are all those witches I am supposed to kill? (Exodus 22:18)