I have a browning silver 12 ga. 3-1/2. I have polished the barrel and tried 4 different chokes with mostly poor results. I have shot the jelly head 670, Indian creek in 665 &675 and the factory turkey choke. Shells used were H13 3-1/2" 6 ,7 and MB. All shots were at a measured 40 yds with little wind and temps in the mid 60s. My best #s inthe 10 in Circe with MB and 6 shot were inthe 120s. Got 275 1 time with 7s, but not consistent. All shots were on 36 in paper
I had similar experiences with my Silver prior to polishing and having my 7 lb 10 oz trigger taken to 3lbs with no creep and travel but I was also overchoking the gun......
I went straight to Nitros after a lot of frustration and the modifications were made and the gun is currently shooting 270-280 in a 10" circle at 40 yards with an Indian Creek .675.
I guess my only question to you would be what choke diameters are you using? I eventually discovered that my gun HATED anything under .670 and that .675 was optimal.
I now have a IC 675 , but the jelly head 670 did the best. I have ordered a rhino 670 and getting a couple nitros to try
What is the barrel length of the gun?
I have a silver and love it now. Out of box with factory choke it sucked. I ended up with .670 JH, put a tru glo sight, polished barrel, and it throws great numbers. I shot Nitro and Hevi 13. Actually the .675 JH with Hevi 13 #7 gives best results with mine. To me a sight is a must.
Check the magazine cap make sure it is as tight as you can get it. Make sure there is no oil inside the bore and that the bore is clean. To clean my barrel before shooting I use carbureator cleaner (cheap alternative to gun scrubber). Hang in there it will come back to you.
Gun is a nwtf edition with 24" barrel. came with sights but i took them off and added a set of tru glo magnum gobble dot pro series.
thanks for your info guys.