There is more effort to bolt lift in the M98 because the firing pin fall is longer. The M98 has more firing pin energy than a M70 and misfires in M98 are rare, but I have had misfires in M70's.
At the time, middle 30's, smooth bolt operation was the rage in the gun magazines of the era. The M1903 was particularly smooth and patriotic Americans were “finding” reasons to support their 03 over the M98. The Mauser design is the more reliable , safer, stronger action, but those considerations were thrown over the taff rail , because the 03 had less bolt wobble and was smoother in operation. Because this was an important characteristic to the group think of the time and something promoted in the press as a superior attribute, you can bet the M70 designers paid attention to making their action very slick and smooth.
And so it is, and they adopted the same cone breech as the 03 and basically ignored gas venting. In this regard, the M70 is as bad as the 03, and inferior to the M98. While a pre 64 action is a very reliable action, from a parts breakage viewpoint, it is still inferior to the M98.
Still, I like my M70's and still shoot them in competition.
Back in the day when bolt rifles ruled the firing line, a pre 64 M70 action was widely used to build target rifles. A stiff action, the ease of bolt lift, smooth and slick action, fast locktime, made an excellent basis for an across the course rifle.
Rarely do I shoot my target M98. There is nothing you can really do to make it as slick and smooth as a M70.