7.62 can on a 5.56 barrel...

I am looking to purchase a Gemtech HVT QD can for my 5.56 AR. I want to go with the bigger can so I can use it for multiple applications and I know there is about a 2db or more difference when using a 5.56 round with a 7.62 can...no big deal. My question is that I have to use a 7.62 flash compensator in order for the HVT Quickmount to fit on the 5.56 barrel. What effect does a larger bird cage have on the smaller caliber 5.5.6? will it work as well as a smaller 5.56 cage or is there a difference? (of course I am talking about firing the rifle without the can attached).
Anyone here have any experiences using larger cans on their 5.56 barrels?

My friend has a HVT that we both have used on everything from 5.56 AR's to 7.62mm AK's and G3's. Get the normal 5.56mm bi-lock for your AR. The HVT will index right onto the bi-lock, you do not need to put a 7.62mm flash hider on your 5.56mm gun.

Besides, the 5.56mm barrel is a different thread pitch than what the 7.62mm adapter will work with (1/2x28 as opposed to 5/8x24).