I have 2 GSP's, one is 2 an a half, the other is 6 months. When its just me an one of them an i throw a bumper or ball for them to retrieve they'll usually bring it back with no problem (epecially Abby the older one) however once they're both together, if i throw a ball or bumper out it turns into a keep away match an neither ever make the retrieve because they're too worried about the other one taking it away. Abby has been known to do this out in the field with quail as well. Any thoughts on how i could throw a ball an the first one out of them to reach it wins an they bring it straight back to me?

Why not throw one out for both of them?

Just a wild guess, but could you call off the dog that doesn't retrieve the item? That way the other could make the retrieve. If you worked on this and took turns, possibly you could get them to work together. I am sure it would still be a race to the item. Just a guess. I only have one dog.

x2...or play with them individually.

Here's a personal experience that sounds kinda similar.....
Several years back, my wife got a young choc female. Sent her to training, and she came came a retrieving monster! Couldn't have been happier with her progress. But when I would play with both labs in the yard, my older male would growl when the female would get close to the ball. She eventually QUIT retrieving tennis balls. I mentioned it to the trainer, who quickly said, Fisher (my male) has essentially taught her not to touch HIS ball. I started seperating the dogs at play time and she started retreiving the tennis balls again.

Why are you sending two dogs after one bumper?

Teach them to be steady. Then send one or the other. If you send Abby and pup breaks, scold him. Have them take turns and make them understand that if they don't sit quietly, then they won't get sent to fetch.

Oh...maybe I misunderstood the original question/issue. I thought it was mainly just at playtime.
If you are "working" the dogs, they should definitely be taught to honor, like BirdDog says above.

Throwing a ball or shooting a bumper is great for your dogs. But first your dogs need to be "here" and "whoa" broke. This time of year i do this alot. I will do this with 2 to 4 dogs never with just one. I start with just throwing it and letting them retrieve it back. I'll do this in the back yard and in the field behind my house. Then i'll whoa them and do the same. Thay learn to mark and it will help the "whoa".Then i will whoa the dogs and i will shoot the bumper over the house into the field with them blind of seeing where it went and release them and tell them to fetch. At times they will come back empty handed, just take them out and look for it with them saying "dead" till your dog finds it. you will be surprised at how well all of this helps in the feild.In all, you are working on "here" "whoa" "fetch" "hold" "give" hunt dead, marking and by running more than one dog racing for the ball or bumper your dogs will really bulk up and help them get in shape. To answer your ?? your dogs need to come when called. Hope this helps.

Play time or not I use both as a learning lesson.... Every time I throw a ball to my dog (champ) we work on sitting staying waiting and fetching on command then when he brings it back i pet him and tell him he's a good dog and stuff like

Thanks for the suggestions. Even if I throw a bumper for each of them, when one sees the other going for a ball they redirect their path to go after the other one. I guess I could send them out one at a time. And when we are hunting just call whichever one didnt point the bird i just shot back to me.