Slugged barrel sizes

[ovenpaa]

I slugged a couple of .303 barrels today and have the average results of:

Rifle one gives me a fairly steady .3120"

Rifle two gives me a fairly steady .31232

Are these acceptable tolerances and what range of cast boolit diameter is suitable?

[Christel]

What's this "I"?

For the record, I held the rifles...

[Alpha1]

They are OK you need a boolit sized to .313/.314 Lyman do a mould in .314 that I have had some good results with in .303 rifles.
I am asuming those measurements are your rifling groove size.

[ovenpaa]

Yes this is from the slugs so will be into the groove. I have some of Dodyrog's .314" 190 grain cast boolits to use so I am off to measure my COAL next.

[Alpha1]

Sounds like your into the groove m8 :lol: :lol:

[ovenpaa]

Allowing a 5 thou jump gives me a build length of 2.880" with the 190's does this sound about right? This cast boolit lark is very new to me.

[dodgyrog]

I'm amazed you can measure to 5 decimal points! What kit are you using?
Good luck with the boolits.

[ovenpaa]

I was using a Mitutoyo digital micrometer than measures to half of a tenth of a thou (And it is in calibration as well!) Such accuracy is quite pointless as the difference between a warm and cold day is measurable on a 25mm block of stainless.

[pe4king]

I was using a Mitutoyo digital micrometer than measures to half of a tenth of a thou .

isnt that a gnats cock?, its been a standard unit of measurement as long as I can remember