Springfield 1903

[Rakkasan]

With a Forster gauge set, that means you are within .006" of "go," so you are plenty good!

Thanks I’m also waiting for my muzzle wear erosion wear gauge tool to come in.

[Rakkasan]

Thanks I’m also waiting for my muzzle wear erosion wear gauge tool to come in.

Muzzle wear was 1.5 on the gauge, I’m assuming that is good?

[MAC702]

Muzzle wear was 1.5 on the gauge, I’m assuming that is good?

"Probably." Muzzle gauging is not an exact science, and more of a relative thing, once you know what normal is for that exact barrel design (and gauge).

Do you have other .30 cal rifles to play with?

[Rakkasan]

"Probably." Muzzle gauging is not an exact science, and more of a relative thing, once you know what normal is for that exact barrel design (and gauge).

Do you have other .30 cal rifles to play with?

I don’t

[oldfoneguy]

1.5 is not terrible especially for an 82 year old barrel. Many early replacement barrels were 2 groove, is your barrel a 2 or 4 groove?

[Rakkasan]

1.5 is not terrible especially for an 82 year old barrel. Many early replacement barrels were 2 groove, is your barrel a 2 or 4 groove?

I’m not sure

[oldfoneguy]

I’m not sure

I tried to photograph 2 of my barrels, my Garand while dirty is pristine and a perfect example of 4 groove Springfield rifling. The 5th line is just copper from firing. I really need to get to cleaning these rifles after the holidays.

Second is the only 2 groove I own a Maltby Enfield No4 MKI. It is also dirty and kind of hard to see but it is exactly as described. 2 large flats and 2 grooves, in this case the 2 copper color lines to the left and right.

The 2 groove was adopted by the allies as a wartime expedient faster and easier method of producing barrels. They provided acceptable accuracy and were indeed faster to make early on. Eventually it was found that production had met the pace of necessity and Enfield and Springfield both returned to conventional rifiling.

[Rakkasan]

1.5 is not terrible especially for an 82 year old barrel. Many early replacement barrels were 2 groove, is your barrel a 2 or 4 groove?

I believe my barrel is a 4 groove

[oldfoneguy]

I believe my barrel is a 4 groove

Ok, that will give a more conventional reading on the erosion gauge than a 2 groove barrel does. I've found that different types of rifling hold the gauge differently. For example 2 groove to 4/5 groove, button rifling to flat, Savage commercial to Savage Enfields and the list goes on. It's a matter of feel to know exactly when the gauge is seated properly in some or direct and unquestionable in others.

[ssgross]

If we are spitting hairs here...the multi-diameter muzzle gauge is not the end of the story. A muzzle gauge must be read proportional to bore diameter. So you know the max diameter at the muzzle...but relative to what? Bore tolerances were something like 0.2995 min to 0.3015 max for the m1. I don't have my 1903 reference at hand, but I would imagine something similar. So you see your 1.5 reading could be a pristine NOS barrel or it could be well used. Using both a muzzle gauge, the actual bore diameter (from pin gauges or slug the bore, or both actually if you want to know all the details), and a throat erosion gauge tells a more complete picture of how "used" your barrel is. For comparison I have a rack grade garand hanging on my wall. The muzzle reads 1+, the throat is at 9+. The bore is pristine. It was well taken care of, even though it was shot...a lot.

Headspace is safe. Stock fits tight. Go shoot and enjoy!