28GA FH new slug.. The Lyman cast 20ga slug made to
fit in a 20ga shotcup for 20 ga slug hunters, works perfect
in the 28GA FH brass case. It is a hollowbases hourglass
shaped 362 gr slug. No wadcups or wads needed, loaded
right on powder. It is the slug you buy the molds to cast
your own or you can buy them from guys who cast for
sale. I use slow rifle powders in case so no air space,
they fill to the slugs. I got 2900 with moderate case
expansion and it hits target straight on, from a smooth
28ga heavy barrel on 695 Mossberg bolt action.

Other new info on primers. Some of the guns can't have the
firing pins or hammers beefed up easy like my Enfields
With some magnum primers with hard cups you get delayed
ignition if hammer doesn't have perfect hit and high strength.
One test with a small diameter case/bore that any primer will
ignite slow powders fine with good firing pin spring would
show delayed ignition with shotgun battery cup style 209
CCI Mag and 209 Federal Mag primers, and when I tested them
in cases with just the primers, they only put in a small dent
when they fired, but WIN 209, REM 209, RWS 209(used in
Brenekkes, Lightfields, Hastings), dented in much more when
firing just the primer. And with the smaller bore you had fire out
the end of the barrel, so you could compare primer strength
visually. The REM 209 was as good or better than CCI and FED
209 Mag Primers. The WIN and RWS was close behind. We put
the REM in same case/gun where that we had delayed ignition
and it fired instantly, no delay. The two mag primer brands have
the primer insert in cup rounded a lot and little harder metal,
and the other 3 metal cup insert is almost flat and slightly
softer. It is easier to get a better more solid strike and dent.
I always figured mag primers were best in our hopped
up shotgun loads but not anymore. It took a while but I finally got
everything around for proper test. Hopped up loads(regular also)
we have talked about, use REM 209, where the firing pins
and hammers can't be strengthened. Even loads with Longshot,
Blue Dot, Steel, HS6-7, etc.
Hope this helps.....ED