I recently installed a Mcgowen varmint barrel on my Savage 11 .243 . I took it to the range with some handloads and factory loads. The factory loads shot fine, no soot. But my handloads had blowby on the brass and the bolt face. The primer looked fine, it didn't back out, so I'm assuming the head space is ok.
The handloads were a start load, with a 55 grain nosler bt. I full length sized the brass because they wouldn't chamber. I know... I know... I should have partially sized them. Whadda ya think?