M28/30 ammo question - I can’t figure this out

[AchNgnt]

I finally added an M28/30 to my collection. I just have absolutely zero understanding of ammo choices. Reading this forum and Gunboards I get even more confused and have read the following:

All were bored to 308.
Some were reamed out to 311 by using commie ammo during the war
Shooting 311 in a 308 bore is ok
Shooting 311 in a 308 bore is not ok
Sometimes they are 310 bores

It is a 1940 SKY in great condition but who knows what’s been shot through it in 84 years.

I will slug the barrel but is there a standard to follow with this rifle? I do reload so I just need to know what bullets to buy and would prefer to avoid slugging if I have the chance as I don’t want lead in the bore.

Thanks!

[Insignificant Git]

Manually pushing a piece of lead through your bore to then measure the slug and determine your bore diameter will NOT result in leading of your barrel. If you want the best accuracy out of your reloads, slug the barrel and get a measurement of the actual bore diameter to get a better starting point for your reloads. Otherwise just start by loading some .308 bullets and try them out. If you get good results accuracy wise, you are good to go. If your results show that .308 bullets have too much windage and they are tumbling within 200 meters, then perhaps you should consider going slightly greater with bullet diameter. Of course you could consider having a gunsmith check your rifle for you, and get the correct measurements that way. The Finns did develop a 7.62x53R standard round after all, and your chamber may not actually be 7.62x54R as you may be assuming.

[Darryl]

Round length 53R: 77.00 mm 54R: 77.16 mm
Case length 53R: 53.50 mm 54R: 53.72 mm
Rim diameter 53R: 14.40 mm 54R: 14.48 mm
Bullet diameter 53R: 7.85 mm 54R: 7.92 mm

It was my understanding that the Finn's changed the "chamber" but the barrel was the same as a Russian. They reamed the chambers out to fire Russian. But it's been years now.

Darryl