The magazine cap screw which goes through the barrel mounting lug and into the magazine end cap has a lttle circlip "keeper" on it. remove this keeper and the magazine cap screw comes out. You will have to do this any time you change barrels anyhow unless you get a spare cap screw.
I fashioned a flat piece of steel with a hole in it for the cap screw to go through, and bent over to accept a forend sling swivel.
This goes under the head of the cap screw when you are mounting a barrel. By now, I'm sure someone has made an equivalent device to accomplish this. The circlip is stored away somewhere for safe keeping and not used in this application.
I'll post a pic later on this device (see EDIT below). I made it, as I say, decades ago, as a quick expedient, and it served so well that I never bothered to upgrade it to a prettier one.
..........
If there is a trap range around you might want to try some trap out, don't just concentrate on buckshot only. Birdshot is relatively cheap compared to buckshot or slugs, and there is much less recoil. The more you shoot the more comfortable you will become with your gun.
While you are practicing at the skeet or trap range, hold the gun at low ready and other positions in which you might actually be carrying the shotgun before yelling "pull." You are not out to hit 25 x 25, but to simulate real conditions where shots appear while you're just walking around doin' nuthin'. Most of the folks who are out there shooting skeet and trap start from the shoulder-already-mounted postion, ready to shoot.
I would go out there and practice with the shotgun slung over my shoulder, just as if I were taking surprise shots while walking through the fields and forests.
[SHOULDER SELF PAT]
With this kind of more realistic practice, I was hitting 15 to 18 X 25 clays out of the high house, with a companion yelling "pull" for the surprise effect
with a 30" full-choked goose (or trap) barrel.
[/SHOULDER SELF PAT]
Yes, I was getting wierd looks and smirks when I took my position with the shotgun slung over my shoulder, but I felt I didn't need practice in walking around the woods with my gun at the pre-mounted-to-the-shoulder position.
This, mind you, was long before we civilians got interesting in "tactical" shooting, and probably long before that word was applied to any kind of shooting.
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EDITED TO ADD:
Pix of the sling attachment I put together "just to try it out" decades ago. Rough & dirty, but worked well enough that I left it alone. The piece was made from a hunk of chrome plated steel and in finishing it, some of the chrome wore off, revealing the copper underplating. That's why it looks discolored in spots.
As one manufacturing engineer once told me, "Perfection is the enemy of production."
The first pic shows the quick-detach "swivel" open, ready to remove the sling. Second pic, disassembled, is slightly blurred. Apologies for haste, but once again,"Perfection is the enemy of production."
I wanted to get pics posted in a hurry.
