Accept this as a given,all Ruger SA pistols are made to shoot low so you can fix the sights after you have picked a load your going to use in that gun.
I will assume you and your friends are pushing the gun to the left when firing it.
If you are using lead bullets the diameter of the bullet should be at least .001 larger than the groove diameter.
Each time you shoot a different weight bullet it will hit in another place.
If you shoot 3 bullets of the same weight all 3 should hit in the same place.
Stop blaming the bullet or the gun its you. Start again using the lightest weight bullet such as a 200 grain and stay with it until you learn how to shoot a RSA pistol.
Making sure the gun is empty practice home some dry firing to learn sight picture and finger control.
The sight picture should be the front blade in the center of the rear sight,you should be able to see a bit of daylight on either side of the blade.
The top of the blade should be equal to the top of the rear sight.
Here comes what your probably doing wrong.
Bring the hammer back.
The pistol is in your hand firmly but not squeezing, the front pad of the trigger finger is on the trigger loosely but not leaning,pressing against the side of the gun, concentrate on this, slowly squeeze the trigger. If your trigger finger leans on the low side of the receiver you will push the shot to the left.
Practice, its easy, forget now about the gun shooting low.
Now, you should be hitting one hole only at 10 yds thats what the gun can do GOOD LUCK Lee