With most of the Top 150 free agents under contract and NFL rosters coming into focus, at least three teams must really, really like the way they draft.

Despite a ballooning salary cap, the Pittsburgh Steelers, Los Angeles Chargers and Houston Texans are the only three teams to sign one external free agent or less since the league year opened March 9. Houston's trading of Brock Osweiler was a deft salary dump and grabbed the rest of the league's attention, but as it stands the Texans haven't signed a single free agent coming from another team.

A modest free agency plan isn't uncommon for a team like Pittsburgh, which traditionally eschews the early-March sweepstakes and prefers to re-sign its own players. The Steelers' only signing outside its locker room is journeyman receiver Justin Hunter.

But the $167 million cap -- a $47 million increase since 2011 -- has enticed 27 of 32 teams to sign or trade for at least three new members. The Kansas City Chiefs and Cincinnati Bengals have signed two new players and re-signed many others, while the Chargers spent $25 million guaranteed on left tackle Russell Okung, their only signing.

Through 11 days, the per-team average is 4.4 new players signed. The San Francisco 49ers basically turned over nearly 30 percent of their team in less than two weeks, acquiring 14 new players this month.

Though inactivity in the new landscape is a bit surprising, the list of teams being inactive are not. The Chargers, Steelers and Texans have drafted well in recent years and are considered to have pretty deep rosters. That's why they are choosing to re-sign their own players, which the Steelers have done with Antonio Brown and James Harrison, among others. Houston, for example, can let cornerback A.J. Bouye walk because first-round pick Kevin Johnson is coming back from injury.