I just got a new 458 Socom about two months ago. I knew going in this was a "reload" only type of caliber and I reload so no problems there. Certain times of the year it seems 458 SC ammo becomes impossible to find as cases are made once a year and there are only a handful of "Factory" ammo makers, period. That being said ALL gas systems will not work with ALL ammo. My first outing I used some SBR factory ammo. Shot fine, did not cycle the action at all. I have a mid-length gas system and this has proven to work with only certain types of powders such as IMR 4198 and my favorite, Reloader 7. Once I pulled those bullets and used RL7 it worked great.
This video shows the weak ejection caused by the use of powder such as H110.
http://dl.dropbox.com/u/10728824/Gun.../slomo_458.wmv
This one shows the good ejection using RL7 powder.
http://dl.dropbox.com/u/10728824/Gun...7_37.5_FTX.m4v
I like it, it's a hammer for sure, and it fits in an AR platform.
