Re: Rifle easier to find than .357
I think that Dewey guide is made so that there are no sharp internal areas, that might scrape the coating. Thus it is a "coated rod guide". "Buy our special 'coated rod guide', instead of someone else's guide, and you won't damage your coated rod". I'm pretty sure it would be fine with a regular rod.
The "27 and up" would be nice if you had several different calibers of guns. You wouldn't need to buy a rod-guide for your 270 and another for your 308 and another for your 8mm, etc. But if you just have the one gun, the "made for 35 caliber" one would be fine.
When talking about rifles, "Small Bore" is 22 rimfire.
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