Benelli M1 SBS Help Needed

ASH556 · Mar 8, 2016

Hey guys, I know this isn't really a 3gun question, but this is where all the Benelli experts are, so here goes:

Last year I bought a new in box, old stock HK Import Benelli M1S90 14" Entry Model SBS. It has the smooth receiver and notched/rifle sights, pistol grip stock, and factory + 2 extension. I took it home, lubed it per manual, installed a Surefire forend and took it to the range. It will not run reliably with Federal LE1321B, which is supposed to be the premier defensive buckshot load. It WILL run slugs 100%. Other buck loads are maybe 70% successful and birdshot is a joke.

By contrast, my 28" field model with +9 extension will run light target loads (Estate, Gun Club, etc) 100% even with a fully-loaded gun. Now I know folks say Benellis are weight sensitive because of how the inertia system operates, but that little 14" gun is waaaaay lighter than my 28" competition gun, so it doesn't seem like it should be too heavy for the inertia system. Also, I asked Benelli about different springs between the guns and they said all their guns use the same springs....not sure if I believe them.

Other potential points of note: 28" comp. gun has factory straight/field stock with Limbsaver. 14" Entry gun has factory pistol grip stock with factory recoil pad. Maybe between the pistol grip stock and the stiffer factory pad I'm not letting the 14" gun move enough?

Any and all help is appreciated!

Pics:

Wall · Mar 8, 2016

ASH556 said:
Also, I asked Benelli about different springs between the guns and they said all their guns use the same springs....not sure if I believe them.

I can't imagine why they'd be any different.

Try loosening the stock a bit. A great shotgun builder once told me the stock can be too tight causing cycling issues.
Not loose, just not torqued.

jtischauser · Mar 8, 2016

That pistol grip stock can cause all sorts of issues. I know I remember Benny Hill posting something about overtightening them or having them crokked or something that really jacks up what it will run. Hopefully he sees this thread. if not send him a pm.

mike cyrwus · Mar 8, 2016

swap the stocks on em and shoot

technetium-99m · Mar 8, 2016

I think I need one of those.

Professor · Mar 8, 2016

Nice! Maybe I need to swap you a 870 for it!

View attachment 11128

technetium-99m · Mar 8, 2016

Are those factory guns? Or did you chop one up?

benny hill · Mar 9, 2016

Take the light off & see if it runs, if it does it is to heavy with it.If you use mag buckshot or slugs it should run. It also uses a heavy recoil spring, replace it with standard spring.You might need to drill crossplate hole bigger to not put a bind on tube.

Professor · Mar 9, 2016

technetium-99m said:
Are those factory guns? Or did you chop one up?

Both Benelli and Remington make factory Short Barreled Shotguns (SBS). I wanted to buy a Benelli 14" Entry model when I bought the above 870 in 1994. However department firearms policy limited us to an 870 at that time and they wouldn't approve a waiver. The 870 above was built by Scattergun Technology when they were based out of Nashville, TN. They were purchased by Wilson about 12-15 years ago and are built in Berryville, AR now.

The 14" SGT will put 00 Fed Tactical fully in a silhouette at 25 yards, as tight or tighter than factory Remington 870s. The factory 14" wouldn't go past 15 yards keeping everything on target. Head shots using slugs were easy with the ghost rings. The AR platform has taken over as the duty long gun of choice and you don't see as many now.

ASH556 · Mar 24, 2016

Well, I got the gun running. The Surefire forend was too heavy it seems. I went back to the stock forend and it runs 100% even with 1200 fps target loads (Remington Gun Club). LE1321B runs perfectly as well. Still wanting a light on the gun for HD, I got a Nordic clamp with rail and threw on an X300U. Everything still runs perfectly. Finally, I added a Limbsaver pad to make the gun a bit more pleasent to shoot - still no issues. At this point I'm pretty well set with it for function. Just need to get it on paper again and confirm zero with buck and slugs.