An arsenal refurb question

[jon_norstog]

I've been thinking about all the posts on this list and the trapdoor forum about bore diameter variability in those rifles. It seems odd to me that good machinists using state-of-the-art equipment couldn't turn out a barrel that was within spec.

last couple weeks I had a lot of time to think while lying in ambush for elk that never showed up. I thought about the rolling blocks we had when we were kids - they had bores that slugged about .446, about .008 over spec, supposedly because the Argentine arsenals broached out the pits in tose old .43 Spanish rifles.

I do know that a lot of rifles came back from service in Cuba and the Philippines in pretty rough shape. I wonder if the arsenal refurbs of the day included broaching the barrels? Might that explain all the Krags out there that won't shoot a .308 jacketed bullet?

jn

[madsenshooter]

The star gauge wasn't invented until the early 1900s, but one would think they would have slugged a barrel as we do. Perhaps it was thought close enough was good enough. To a certain extent that's true. Then along came Hudson and Pope bellyaching about undersize bullets and oversize bores. I shot some 168s out of a .310 groove diameter barrel and wasn't expecting much, but got a 1" 100yd group. I imagine the rifles with bad bores that came back from Cuba and the Philippines were simply rebarreled rather than broached. After all, that's sorta the point of having a barrel that screws into the receiver. It's likely also the reason we often find 92s and 96s with like new bores. Like new, but still often oversize. Boring seemed to be pretty consistent, most all mine are .301" bore, t'was the rifling depth that varied.