You probably will not gain enough speed to actually make a difference, especially with her draw length and the type of bow she shoots.

You might be better off going with lighter arrows, especially for target shooting. If she is shooting for points I would try to make the bow as forgiving and easy to shoot as you can. She should be able to point the bow at the target and smoothly draw it straight back while still aiming at the target. And she should be able to do this 30 times in a row over the time it takes to shoot the course. And she should be able to hold the bow fairly still until she has time to relax and get the shot off. If she can't do this she is over bowed and you should turn the weight back down.

Getting tired and struggling to draw the bow will not help her scores any. If you want her to gain enough speed to help with judgment errors out to 30 yards you will need to get her around 300 fps or so. I don't see you doing that with a 300 grn arrow and that bow.

At 35-40 lbs of draw weight and a 23 inch draw length you could go very light on the arrow and still be safe. A 300 grn arrow would be like you shooting a 500-600 grn arrow out of your bow when you take into account her draw length and draw weight.

To be honest, and I will probably get grilled for this, but if she is just shooting for fun and not trying to compete I would see if she can use a range finder. I use one when I shoot 3-D, but I don't even keep score. I don't guess at yardage when I hunt, so why do it when I practice? I only shoot 3-D to practice shooting at deer sized game and get a feel for shot placement at different angles. I don't score by the ring, I worry about if it would kill the animal or not. Many times the better score would not be the better shot on live game and vice versa.

These are only my opinions though. My girlfriend shoots 1713 platinums with 70 grn glue in nibs. I don't remember what they weigh, but they are not very heavy. She shoots a rintec at 30 lbs, I think she is shooting similar speeds, around 189 I think last time we checked it.

Paul