I have an opportunity to either buy a Barret m82a1 or a McMillan tactical.  Anyone care to compare?  I know there is a difference in price, but I thought that the Barrett may be more suitable because I'm fairly recoil sensitive.  I don't know a lot about fifty cals, but would appreciate any thoughts you might share.  Thanks

What are you looking for, accuracy or recoil?

Accuracy, go for the McMillan.

Less recoil. go for the M82A1.

Good points.  I want the most accurate rifle possible.  The trouble is that I have a lot of recent problems with recoil.  I have shot so many rounds of 12 gauge skeet it feels like my brain has been knocked loose and floats around my skull.  Four rounds of skeet and my ears start ringing, and my head starts pounding.  I use a auto 20 gauge now.

Stop using high base mags for skeet! Have you thought about getting your skeet barrels ported?  My dad ported his 1100 at work and it makes a big difference.  A little louder but softer on the shoulder.  

It sounds like you may need to see a doctor.  What type of muffs are you using?  I can shoot 4 rounds of skeet and 4 rounds of  trap and the only thing that bothers me is my neck from getting a good cheek weld.  

As for the .50.  Are you just limited to those two rifles or are those your personal choices?  How much are you going to be shooting it?  I'd go for the McMillan.  I don't foresee having the need to dump that much lead downrange anytime soon.  A bolt action repeater suits me just fine.  I envy you for having the option to purchase a M82.  Those are just too evil where I live!

Recoil reduction solutions for competitive shotgun:

(1) make SURE shotgun fits!  Go to an expert.
(2) 1 oz loads are just as effective in my opinion
(3) ported barrel(s)
(4) mercury reducer in stock or lead in hole -same effect different price.

See a doc, you shouldn't be havingthese kinds of problems.  If you shoot something big, you my tear a nerve causing blindness, deafness, death.  Be very careful!  Sounds like you have a serious problem!