Gold tip spine and weight question

I currently shoot Gold Tip 5575/400, the length of my arrows with nock and tip is right at 28". The weight of my bow is at 68 or 69 pounds. According to the Gold Tip arrow selection chart I should be shooting 340s. Is this going to make a huge difference? Or is that chart more of a guideline than gospel?

yep, you are way under spined. Get it right and your groups will really tighten up, especially at longer ranges. Fixed blade broadhead flight will also greatly improve.

It makes me somewhat relieved and frustrated. The frustration comes from months of trying to figure out why I have issues with grouping well at long range. But relieved cause I am going to go get some 340s today and I am looking forward to seeing if there is a difference. Thanks for the response!

3Blade is correct, too week of an arrow will cause consistency issues especially at long range. If you are shooting the Expedition, XT or Pro Hunter 5575/400 you may look at the Velocity 340 it weighs the exact same as that arrow but has a stiffer spine.

So this reply is going to two different issues I posted on this page. The whisker biscuit fiasco, and the proper spine issue. So I took the advice from all of you guys and have made a few changes and I am very pleased with the results. I got rid of the whisker biscuit and got the Hoyt QAD. I changed out my 400's and went to the 340's. I added one more change and added helical vanes. Ran it through the chronograph, lost 10 FPS. Everything was going fine at normal distances, I noticed that I never had the occasional flyer that made you sit and wonder what the heck caused it. I had to make a pin adjustment at 60, and 70. But at 70 my shot group was literally cut in half from before! Just to make sure I wasn't just getting lucky I did it a few more times. I shot a six inch group with 5 arrows 3 times. I am very pleased. Yea I lost 10 fps, but I feel more confident that I won't have any unexpected flyers anymore which is good to me!