Accurizing a sluggun- Pinning the barrel help!!

[PunchinPaper]

I have heard some people pin the barrels on pump slug guns to make them more accurate. Well I have a New Mav88 I bought cheap and have decided to make it a dedicated slugger.
I have a full rifeld barrel ported with iron sights. I am considering drilling and tapping a hole on both sides of the reciver where the barrel shank slides in and using set screws to (pin) the barrel. If this is truly going to boost accuracy. Anyone experienced in such please advise me. I also have a slug scope I am probably going to put on this Mav as well. I have been looking at options for mounting this optic. Im not sure if I should drill and tap the top of the recever for the scope mount I have or try to find a saddle type mount. As the mav i have isnt predrilled for mounting optics. Any advice on that will also be helpful. The drilling and taping operation is not a problem for me as I am tooled up and capable of doing so. I am just looking for a second opinion so to say before I jump into this.....by the way I know I know it would have been easier to buy a H&R Ultra slugger. But I already have all this so....
Ideas-Info-Advice Please!!

 

[Scorch]

Pinning the barrel is done to keep the barrel and action aligned so that a receiver-mounted scope will give consistent accuracy. Get a cantilever scope mount and you will not have to worrry about it.

 

[Old Guard Dog]

Scorch is right. A cantilever scope mount is the way to go. Besides, you're not going to be shooting 300 yds.