You can keep the default behaviour (with gutter) and add a class to your CSS stylesheet for tasks like yours:
.no-gutter > [class*='col-'] {
padding-right:0;
padding-left:0;
}
And here’s how you can use it in your HTML:
<div class="row no-gutter">
<div class="col-md-4">
...
</div>
<div class="col-md-4">
...
</div>
<div class="col-md-4">
...
</div>
</div>