I bought this Springfield Armory Standard M1A awhile ago and found some surplus M80 ball ammo to shoot through it. I want to use this rifle as an all-around utility rifle for hunting, target shooting and such. Little did I know about M80 ball ammo. The story I got about the 147gr. M80 ball, is that it was intentionally made very slightly under-sized so as to run cooler in machine guns. I don't know if this is the true reason, but the 147gr. M80 ball bullets are physically under-sized. I installed an ARMS #18 mount, which I had to send to S.A. to get installed correctly. I then installed a Nikon 6X42mm Monarch scope on it. I could not group well with it and was concerned about the rifle, the scope, the mount, the ammo, it was printing about 8-10 inches at 100ds. A gentleman at the range came over and inquired about how things were going to which I replied not well. He asked about the ammo and blamed it for 90% of my accuracy problems. So we removed the bullets from some of the M80 ammo and installed some Sierra 168gr match boat tail bullets in their place and the groups shrunk dramatically to about 2-3 inches at 100ds.
I finally received my Sierra bullet order, 1,000 150gr. spbt bullets and changed out about 550 M80 bullets with the Sierra bullets and then back to the range today. The first couple of groups were good with him shooting and then myself shooting. After a target change, we shot again and the grouping stayed about the same but moved. They were up from center, then down from center. What we realized was the grip we were using to steady the rifle on the rest, when we gripped forward on the forearm just forward of the magazine the groups went high. When we gripped the aft end of the stock with our free hand the groups went towards the bottom.
So a bedding of the action is in order and we believe that this should remedy the wandering groupings.
But it's been an interesting ride and I have learned alot. As I have not done any kind of bedding work before this will be another learning experience and I hope it will make a good shooting rifle even better.
I finally received my Sierra bullet order, 1,000 150gr. spbt bullets and changed out about 550 M80 bullets with the Sierra bullets and then back to the range today. The first couple of groups were good with him shooting and then myself shooting. After a target change, we shot again and the grouping stayed about the same but moved. They were up from center, then down from center. What we realized was the grip we were using to steady the rifle on the rest, when we gripped forward on the forearm just forward of the magazine the groups went high. When we gripped the aft end of the stock with our free hand the groups went towards the bottom.
So a bedding of the action is in order and we believe that this should remedy the wandering groupings.
But it's been an interesting ride and I have learned alot. As I have not done any kind of bedding work before this will be another learning experience and I hope it will make a good shooting rifle even better.