Benelli MP 90S

Purchased the Benelli MP 90 that Cabela's had listed on their web site.  Would like to mount an Ultra Dot - Micro Dot on it.  Can anyone recommend the best approach?  Likely it will have to be drilled and tapped, but is there a way to mount that on the rear sight part of the pistol, could also go with a different type of optic if there is another way.  Looking to someone who has a setup for this type of pistol.   Any suggestions are appreciated.  Pictures of someone who has some setup like this would help.  Thank you.

Try this - https://www.redfeatheroutfitters.com/benelli-scope-mount.html

I agree Zippy's suggestion as the best by far, but you can also get a picatinny to 11mm converter and mount your micro dot fore of the chamber.  It also works to mount a regular red-dot with medium height 11mm rings directly to the small rail that is on the 90s frame.  In that case the rear ring will not have 100% of the gripping surface attached, but enough will get on behind the chamber that it holds just fine.  Photo shows the mount Zippy suggests when installed. Whats nice about this is you can clean the gun without re-zeroing the dot.  You just take the mount off and it goes back on exactly as you took it off.  Depending on how your MP90s ejects shells, you may need to relieve a bit more of the exit opening on the mount, but usually not.

hammer6048 wrote: Likely it will have to be drilled and tapped, but is there a way to mount that on the rear sight part of the pistol, could also go with a different type of optic if there is another way.  Looking to someone who has a setup for this type of pistol.  

The Larry's mount is a perfect fit and goes on and off perfectly too. However, it adds a good bit of weight (to say nothing of the optic you put on it), which can be good or bad depending on your strength and endurance.

If you decide to drill and tap, beware - the frame has an incredibly hard surface treatment, and there's not a lot of metal between the surface and the barrel (front) or bolt (rear). You need to find a smith who really knows what they're doing.

That said, it can give great results. I drilled mine, with two blind holes in the saddle area behind the chamber, and in front of the rear sight. The pistol functions and balances perfectly with smaller sights, including an Aimpoint H1, and I love it. An Ultradot Micro would work well there too. Sorry, no chance to take a picture but I'll try to get to it next week if you are interested.

-TT- wrote:

hammer6048 wrote: Likely it will have to be drilled and tapped, but is there a way to mount that on the rear sight part of the pistol, could also go with a different type of optic if there is another way.  Looking to someone who has a setup for this type of pistol.  

The Larry's mount is a perfect fit and goes on and off perfectly too. However, it adds a good bit of weight (to say nothing of the optic you put on it), which can be good or bad depending on your strength and endurance.

If you decide to drill and tap, beware - the frame has an incredibly hard surface treatment, and there's not a lot of metal between the surface and the barrel (front) or bolt (rear). You need to find a smith who really knows what they're doing.

That said, it can give great results. I drilled mine, with two blind holes in the saddle area behind the chamber, and in front of the rear sight. The pistol functions and balances perfectly with smaller sights, including an Aimpoint H1, and I love it. An Ultradot Micro would work well there too. Sorry, no chance to take a picture but I'll try to get to it next week if you are interested.

 What you explained is exactly what I want to do.  I have an extremely capable experienced gunsmith who I have do my work, will pass the info on to him.  Yes if you could send some detail photos, that would be appreciated.  The Larry mount and more weight is not what I care to do, the nice thing with the purchasing from Cabelas, the man at Cabelas in Nebraska said "you don't like it when you see it at your Cabela's you don't have to take it".  That was my concern is how much meat there is between the surface to the bolt.

or, if you can find one.
formerly offered on the forum
you have to saw off the front extension, but it holds very well.
The Benelli extractor is well known for throwing through a 180* range!

croesler wrote:I agree Zippy's suggestion as the best by far, but you can also get a picatinny to 11mm converter and mount your micro dot fore of the chamber.  It also works to mount a regular red-dot with medium height 11mm rings directly to the small rail that is on the 90s frame.  In that case the rear ring will not have 100% of the gripping surface attached, but enough will get on behind the chamber that it holds just fine.  Photo shows the mount Zippy suggests when installed. Whats nice about this is you can clean the gun without re-zeroing the dot.  You just take the mount off and it goes back on exactly as you took it off.  Depending on how your MP90s ejects shells, you may need to relieve a bit more of the exit opening on the mount, but usually not.

 
The 11mm rings are the way to go. I had two Benneli's with the Larry's/Red Feather mounts. They are slick but I had too many stove pipes. Once I went with the 11mm rings the stove pipes stopped. RMMV.

Bill

Couple of options if you have a older one with 11mm groove and quasi picatiny. Mono ring mount front or back or bridge with two rings . larry mount.

Holosun setup above looks good if the front lense can stay clean..

I shot mine for yrs ULTRA DOT with front mono ring, first with BME ring and than modified Leupold that could be more easily removed for cleaning or replacing firing pin.

The biggest issue is the Benelli throws brass almost straight up most of the time and empties bouncing off dot back into action can be a big relibility issue. The higher the dot the less issue in my experience. Rtv'n a small metal deflector on bottom of dot helped a bit. 

Definitely scrounge up some spare firing pins you will need them.

I have 2 MP90's a 22 and a 32. I tried the Larry's mount, very well made, fits perfectly, but makes the gun very node heavy. I use the 11mm rail with tall mounts. I also use a 1" Ultra Dot, it does not block the case ejection as much. You have to remove the scope to clean the gun, but I just attach with the front mount level with the breach face and I have had no problems holding a zero. 

Graham

Thank you for the photo of your setup. Take care and keep them in the 10 ring.

The Benelli is a heavy gun and nose heavy with the Larry's mount. +1 on the larry's mount cause problems. Medium Rings and cutting a notch over the ejector port is a an idea better Idea is to go with 11m adapters or 11mm rings. 

Harken Spuhr makes a 11MM base for the Aimpoint H1, Aimpoint makes one too but the Spuhr one is the same price and higher quality. I know that guy and he is a genius. He also is by far the best gunsmith for Lugers in the world.  I would mount it afore of the chamber and it should balance good. Shades should work and keep the glass clean. Mounting the micro dot on the back cut out could be the best solution but with the Spur mount that would likely require the removal of the rear sight, With that mount you should hold zero if it is removed and replaced. 

https://spuhrwebshop.com/en/sm/sm-1900.html

Here is a crazy idea. That pistol has the best set of iron sites i ever shot. If you eyes are good shoot irons.

Here are the rings I used

https://www.amazon.com/gp/product/B01A5ICWFM/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Graham

hammer6048 wrote:

-TT-... wrote:If you decide to drill and tap, beware - the frame has an incredibly hard surface treatment, and there's not a lot of metal between the surface and the barrel (front) or bolt (rear). You need to find a smith who really knows what they're doing.

That said, it can give great results. I drilled mine, with two blind holes in the saddle area behind the chamber, and in front of the rear sight. The pistol functions and balances perfectly with smaller sights, including an Aimpoint H1, and I love it. An Ultradot Micro would work well there too. Sorry, no chance to take a picture but I'll try to get to it next week if you are interested.

 What you explained is exactly what I want to do.  I have an extremely capable experienced gunsmith who I have do my work, will pass the info on to him.  Yes if you could send some detail photos, that would be appreciated.

Here you go.

Originally, I chose a Weaver #85 sight base, which is only about 1 1/4" long and has one slot, and holes 0.860" apart. It is radiused for mounting on .468" rifle barrels, but was easily milled flat. My gunsmith declined to touch the job, but he supported my bravery with good advice to not drill through the saddle. I chose to use metric (M3) flathead screws, and drill and tap 2.5mm blind holes, 3mm deep.

I used a 2.5mm center-cutting end mill, which nearly bounced off the hardened surface at first. But after annealing with a nail chucked in the milling machine, it cut quite well. Tapping was difficult due to the tiny tap in a blind hole, with (great) care it worked out.

I later made my own custom mount out of raw aluminum sight base stock, which you see in these photos. I milled a "step", which fits tightly to the forward edge of the frame, this keeps it quite straight and firm, and the slight overhang is well out of the way of ejection.

Turns out my choice of hole spacing was well-made, I've since created bases for Burriss/Vortex/etc reflex sights by milling down EGW parts (the 49324 and 49425 have the same .860 spacing). I love the Aimpoint Micro, but my injured shoulder needs a lighter option. I'm very happy with the results.

The forum only lets me upload three images at a time, so I'm splitting into multiple posts. The first images show the "in the white" initial piece, then the same piece after cerakoting and installing.

Happy to chat offline about any details!

More photos of the fit and final finish. Note the rounded lower edge of the overhang, it's needed to allow the bolt to rotate upward when stripping.

The holes, and installation

And the final result.

Nicely done.

james r chapman wrote:Nicely done.

+1