Howdy All, Frequent reader but not a frequent poster here for years. I have an Uberti "Special Sporting Rifle" 24" barreled 1873 Win / case-hardened receiver, etc. in the original .44-40 WCF chambering. I absolutely Love this thing and shoot it often with cast bullets. The 200 gr. bullets are .429" and commercial "magma-type" slight-bevel base cast with a hard red lube in them. They are medium hardness that I buy at .430 and side-down so nice and uniform. Bullets are good and tight fit. Probably have 400-500 rounds through it with Unique, BE and (Courtesy of Savvy Jack he REAL Jewel in powders for this thing!) Alliant Reloder-7. Max Velocity is nearing 1,400 fps. with RL-7 H-V loads, but usually 1,000-1,200 for just plinking around with Unique.
Problem is in bore exactly 3" forward of the beginning of rifling. There is a "Loose" spot for about 1" that is a real lead grabber where it "Returns to Regular Bore Diameter" as bullet travels. Also the bore is no super-star with respect to visible tooling and reamer marks. I have one of those brilliant Teslong fiber optic bore-scopes and can see every little detail of the steel with excellent clarity.
I ran 6 LBT Lapping compound bullets through that smoothed up the throat a bit and removed all the tooling roughness off of the beginning of the Lands. Now lands start nice and shiny. Going up the bore I don't see any softening of the very sharp rifling edges or this strange little Loose Spot that has some nasty tooling in fwd. edge. I think i was using 2-3gr. of BE to pop them out.
Question for the gang here is how many LBT Grit rolled Beartooth Lappers do you think I will need to make a noticeable cutting-down of some of the Sharp Edges 2/3 way up the barrel and "soften the Transition out of that little "balloon spot" in bore?? I guess it goes to "How Hard do you think Uberti's Barrel Steel Is"??
Thanks everybody and standing by. Steve in E. Florida