Is this with your handload?

So, maybe both are a little too hot? My 1885 with a heavy (215 grain) gas checked bullet and 4198 powder at around 20 grains will shoot sub MOA at 100 yards out of a sporter weight (maybe ex-GI) barrel and not stick. I've noticed in other rifles in other calibers that the Czech ammo can be loaded on the hot side. My Uberti in 38-55 shoots very well so I wouldn't necessarily question the barrel's quality. I had a rifle that a case stuck in and it turned out it was my mistake in loading (rare!).

Just curious, DH, but are you loading lead or jacketed bullets (with what weight) and with how much 4198? There doesn't seem to be a lot of data on using 4198 in a 303 except for reduced loads with lead bullets. (My 303 is a 1905 Ross, by the way).

Yes, that is only .9 grains under max with no pressure listed. If you go to (You need to Login or Register to view media files and links) you can find loads that are a similar velocity (or even higher if that is what you are trying for) with pressures listed and you will see they can vary considerably. Also note that 4198 is not a listed powder for the .303. I'm sure you know that it is usually deemed best to start at least 10% below max and slowly work up. I'm sure you also know that best accuracy is often found at less than highest velocity.