i have a question. i was wondering if hevi shot would increase my range on my gun my effectve range now is around 30 yrds

If you can keep your pattern dense enough hevi shot will out perform lead shot of the same size. However, hevi-shot behaves differently than lead, and you need to find the choke that works the best.

I have my son set up with a Remington LT20, Rhino extended choke and Nitro triplex hevi-shot loads. He can get 20-25 hits in the kill zone at 40 yds.

..SURE I WOULD SAY IT WOULD,CALL REMINGTON CO..CHAT WITH THEM A FEW SEE WHAT THEY SAY...I ONCE HAD A REM 20 GAUGE,AT 40 YARDS DEAD TURKEY FOR SURE,I WAS SHOOTING A EXTENDED STRAIT RIFLEING TUBE
........AWESUM PATTERNS...KICKED LIKE A MULE..

Well the 20 gauge would work if you got an extra long barrel. But my favorite is a 12 gauge or a 10 gauge with huge turkey barrels. So try your best on getting the big one...