I primarily hunt whitetails and shooting 29" draw at 65 and 70 lbs usually penetration is no problem.
However I decided that I wanted to try a heavier arrow.

I have been shooting Easton Flatline 340s at 8.2 gpi.
I ordered 1/2 dozen EastoN FMJ 6mm at 10.4gpi.

This whould take me from around 400gr total weight to about 460.

Anyone have any feedback on Full Metal Jacket arrows?

I have a couple dozen FMJs for my compound. I like then a lot. I have half a dozen FMJs for my crossbow and they are a better made arrow, but not so accurate as the plain old XX75 Magnum 2219s. Take the best of each and just shoot it for accuracy and they are equal. The next batch of FMJs for the crossbow could very well be as good or better. The difference is not more than 1/4 inch at 20 yards.

I prefer the FMJs for hunting. The extra weight is just cheap insurance for a little extra penetration. The three I shot with them this year did some bone cutting and one was heavy duty bone cutting and I still got two holes.

Thanks for the feedback. I hope to have them in a week or so.