..No problem with custom barrels, but I've never found a need for anything heavier than 162g in my 7mm RM...
that just blows another hole in the 7mm greater bullet selection argument...in that most people only utilise a small selection of whats available,... and likely for two main reasons; - common 7mm barrel twists limit the variety of projectiles one can practically use - the majority of hunters typically have a narrow band of loyalty and/or typical stick to tried and true by experience or on sound recommendation.
People with greater practical sense are more interested in terminal performance , not number crunching highest BCs and energy/vel graph plotted nuances (at the shooting distance limits most people operate within)
Rem700 7-mag 1:9 1/4" twist Howa 1500 1:9:5" Vanguard 1:9.5" Sako 1:9.5" M70 1:9.5" X -Bolt 1:9.5" Savage 1:9.5" Tikka 1:9.5" Kimber 1:9.5"
that puts the super duper BC pills and xtra long monometals out of the game for most 7-Mag owners.
-Bulletproof and Waterproof don't mean Idiotproof.