Thanks Tim. As always you seem to have quite a handle on things when it comes to these H&R's. Maybe you should do some consulting work with H&R for a while and get them updated on their facts etc.
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In any case, it's relieving to know it's more than likely an SB2 frame. A friend of mine who is a very knowledgeable gunsmith and machinist has told me time and again to stop worrying about it and just shoot it but I guess I'm just a bit of a worry wort.
I've noticed that the case coloring (and wood finish too) seems different on my W&H than the newer H&R's which is why I questioned the manufacturing and make-up of frame...year of manufacture and general strength. I like the coloring of the W&H, it seems to be a little more subdued and classic looking. It's definitely a fine looking rifle.
I did read the BC tripod website and it give a very nice history on the rifle and the original owners etc. It's good reading. Thanks!
In regard to your first comment, fitting of barrels; does this mean I probably cant fit a newer barrel to my W&H or does it just mean that H&R won't do the fitting?
Although I'll eventually pick up another rifle, probably the 45 Colt model with the case coloring, I'd like to add a 30-30 to my set-up. I'd love to have a 32-20 or 32-40 as well. I guess that will be a custom job for the future though.
Attempting to get back on the subject of original chamberings, I'm surprised that a 32-20 was never offered in the early days.
Anyway, thanks again Tim.