Since you are shooting at known distances speed means nothing period! If anything a slower arrow is more forgiving becuase it has more time in flight to correct its self.

40 lbs is easier to draw smoothly and hold than 60 or 70 is. Thus letting you shoot more arrows without getting tired, and since speed is not an issue why beat yourself up flinging arrows indoors?

As far as the big arrows he is using it is called line cutting ability. His arrow is bigger around so what would be a miss for you would not be with him. Since his arrow was bigger around it may have cut the line and yours would not have. My honest opinion is he would be better off shooting an arrow that had better spine than slightly better line cutting ability. I have tried it both ways and I shot better with the correct arrow vrs a larger one.

I would be willing to be he let down a lot as well. You watch any good target archer and they let down quite a bit. If the shot does not feel right they let down and start over again. This is why they don't miss as much. A lower draw weight and smooth cams are nice for this as well. Letting a bow down will wear you out faster than drawing one.

Indoor spot shooting really isn't great practice for hunting, other than practicing your grip, form and aiming technique. It also teaches you to shoot under pressure. 3-D would be a better venue for practicing hunting skills. And I would do it the way you intend to hunt, not shoot for scores. Often the better shot on live game would not be the higher score on a target. I know many great target shooters both indoor and 3-D that really don't do that well hunting. And I know many VERY good hunters that are not very good target shooters.

That does not mean you can't use your hunting set up to shoot indoor targets with. It is all about doing the same thing every time. If you shoot well enough it shouldn't matter. I honestly think 5 spots or 3-D would be better with a hunting rig though.

Paul