Just a thought..

[bgcameron]

In regards to Lee Enfield barrels. I'm sure that everyone will agree that the internet is full of phrases like "..oversize barrels" and "slug your bore" and "... known to have groove diameters up to .318"

From what I've seen, a lot of these claims relate to 2-groove barrels. Now my crazy thinking is that a barrel with 2 grooves instead of 5 should have deeper grooves to give the barrel the same "cross-sectional area" as a 5-groove. Therefor the bullet passing through has more room in the grooves to squeeze into.

Am I crazy? Or is am I getting onto something. Thoughts??

 

[ATOM]

Interesting concept. Might be, but I suspect that loose wartime tolerances had more to do with it.

Second thought - not really willing to go to the effort of digging for the specs, but were not the grooves on the multi-groove barrels narrower?

 

[mg4201]

I think that after all that equipment was lost at dunkirk the allies needed weapons so badly that tolerances were probably relaxed a little in order to speed production.

 

[fiddler]

Many milsurp rifles have a range of barrel tolerances, not just Enfeilds. Slugging the bore is always a good idea, not just to determine bullet A or B, but to get an idea of barrel usage and wear. There are people who feel a barrel is worn or "shot out" because it may not group within specs, this is often not the case. Often when slugging the barrel, the rifling is very strong, but the bore is large. For hand loaders its a no-brainer. Going up 2/one thousandths in bullet diameter can give you a two inch group instead of six inch group.

A Mosin 91/30 is a good example of this. a .312 bullet always out performs the standard .310 bullet it was designed for.