Unfortunately no. Nothing to do with whether the brass feeds. Any bullet may be seated far enough down in the necks of .260 REM cases to allow the finished round to fit a std SA magazine length, but for a typical short action magazine of 72mm this will often mean that with the round chambered, the bullet will be positioned well off the lands. I say often because it depends on the cut of the chamber - by how much the lands have been removed beyond the neck to form the freebore.
The 6.5 SLR mentioned by John has the same brass length as the parent .260, so it suffers from the same problem. This issue is covered in the article here:
6.5 Super LR. At the end of the article there are two reamer drawings that demonstrate why magazine fit can be a problem. With reference to these drawings the cut for a SA magazine fit has the freebore at only 0.055" (1.4mm). There is sufficient anecdotal evidence to indicate that the 130-140gr VLD bullets perform better with a freebore of 0.160" (4mm) or somewhat more, described for the 6.5 SLR in the article as requiring a medium or long action length. It does depend on what profile bullets are used, and whether for the application they can be jumped.
Maybe some of the .260 or .260AI shooters on here can reply with their magazine and chamber freebore lengths, and COAL for just touching with VLD bullets, then we'll know the requirements.