Here is picture of our NEF 12ga FH with Hogue Compstock. It has the
recoiling cam and springs in the hollow butt plus some weght,

Here is a variety of slugs and bullets that fit in the 12ga dangerous
game slug, lock on sabot. BPI sells that DG slug.

.

There is couple 585 videos on Swann Gunsmithing's Facebook site;
Of our 585HE in first Ruger #1, that was done in Australia.It was set up
for the poster Tankhunter on the AR big bore forums. That gun killed the
first AUS buff, killed by a 585HE, that I posted picture of above. You can
go direct to the page and click on the videos to watch the test firings..

https://www.facebook.com/swanbarrels/videos

Here is picture our 585HE in a Montana PH action in a MPI stock, with the
style of a CZ stock and metal will be finished with a Gun Kote finish.

Here is picture of a 585HE we did in a Mauser 98 as a
singleshot test gun. We used a composite stock we
adapted to fit action. Weighted to 12 lbs.
Enfield in back, you can see it is longer.

And speaking of singleshots a fellow in the Yukon is
just finishing up one in a Ruger #1.And the 24hr Campfire
forum has over a million views of this thread, ..ED