Not quite pure BS! I did have a box of Remington factory loaded ammo, with old style 250 gr. RN bullets that had so little shoulder and the shoulder was placed so far back that about half of cartridges in the box failed to fire in my Remington M700 .35 Whelen factory chamber. I didn't have a headspace gauge at the time but you could compare ammo form different lots and see the problem just by "eye". Simply a lack of quality control by Remington. I have never had a failure to fire or headspace issues with any other ammunition or reloads or chambers in three other .35 Whelen rifles. The shoulder dimensions / chamber design provides adequate positive headspace, if tolerances are within specifications.
