Hi,

At 1665FPS a 650 grain bullet will produce about 4000FPE. I need 1850FPS for 5000FPE. I was thinking about RL15 and starting at 90 grains and working up. I'm building this on a very stout AYA 10ga box lock action, three bites, side bolsters, side clips, bushed pins, long bar with a massive solid butt stock. I will proof it for factory ammo +20%, which is about +30% my intended load. Barrels are shoe lump and massive as well, gun weighs 9+ pounds. Weight should be around 13 when I'm done.

Hardest thing thus far in the build has been locating all of the proper reloading equipment and supplies which includes brass and bullets. Everybody is out of everything, or never had it to begin with but advertised it anyway. I purchased every bit of brass I've been able to find....20 pieces of 3.25". There must a lot of .577NE's out there, because all the normal vendors are sold out.

bs-