.. 2x7WSM, 2x7RM. A Mashburn will probably not do anything more than what I have (at least that I can utilize) but I like the idea of doing something a little different than the norm.
KDK: I can understand that....
You're more than suitably armed
So the Mashburn is tough to justify.
That said, what drove me to it was many years spent with the 7 RM,which is splendid as is,but when convenient I built them with a long throat and a H&H action,set up to seat heavy bullets "out"...I found this did not give much more velocity(some),but did prevent those funny walls that seemed to pop up as I approached top end.I see this even here with guys running into velocity walls with the cartridge..the cure is generally pretty simple...it's throats and barrels.
I always felt the case body and neck on the 7 RM could have been longer;and since all the rifles I've had for the 7RM had H&H length actions anyway, I might as well use it.
The Mashburn eliminated all these tiny faults (riflemen understand);has a longer neck,more case capacity without going over board,and gets its' velocities,easily, from 24" tubes(it goes even faster, easily, with longer barrels).
What I have found is that it gives that 3050-3075 or so with a 175 gr bullet,and with todays powders,easily hits 3200+ with 160's;even better than Page and Hagel promised, with todays powders.
What Art Mashburn found back in the 50's (there were actually 3 7mm Mashburns),was that going to a bigger case than the Mashburn Super, did not provide significantly more velocity than the Super,and just burned more powder.Hagel discovered this himself working the 7mm-300 Weatherby...maybe not true with todays powders, but a glance at loading manuals for the STW and the RUM points out this is true,especially with 160-175 gr bullets.And avoids the large powder charges and 26" tubes of the larger cases.
Said another way, the Mashburn Super hits a "sweet spot";not too big, not too little,and can be put up in a 24" barrel and under 8 pound rifle,takes reasonable powder charges,and gets velocities close to the larger cases without straining things.
It just works good.While hard for some to justify (understandable),for me it makes just as much sense as a 280 AI,comes in rifles of the same weight and length,and outperforms that cartridge easily.
Whether it is worth it or not is up to everyone to decide for themselves, as with most things shooting related.
