Benelli mp90s

[Rudi]

My pistol is from 1991

It doesn’t have this circled part of the trigger assembly.
Was this added later?

Second question , a while back I asked about replacing the rear sight plate but mine doesn’t have a screw, just a small round “dot” and the plate I have is super thin. I’ll have to grab a pic tomorrow.

[Gwhite]

That is the latest version of the disconnector lever. The original Benellis had no lever at all, but they could fire "out of battery". Benelli fixed that by adding a lever, but the original one was flat across the entire top, and you could no longer dry fire the pistol using the empty chamber plug. The slide had to be closed almost completely (less than ~ 1 mm gap) for the hammer to fall. The version you show allows the hammer to fall when the dry fire plug is in place, but prevents firing when the slide is closed a bit more than that.

The biggest hazard with the original design was from a fired case getting caught sideways between the bolt face and the back of the barrel. Under those conditions, the hammer can strike the firing pin when the back ~ 1/2 of the case is unsupported. The case will explode & can throw brass bits around. With the completely open top on the Benelli, that was pretty hazardous for the shooter.

Many (most?) European target pistols can fire out of battery. I know that MatchGuns MG2 and Pardini SP's will, because I've seen it happen. The breech area is more enclosed on those pistols, and the odds of an injury are very small. I've had 4 or 5 with my MG2. Now that I've fixed the extractor & ejector, I don't get trapped brass and it's no longer an issue.

[Dcforman]

Not to hijack a thread, but what did you need to do to the MG2 extractor? I had to reprofile the ejector to get reliable function. Just curious more than anything else? How old is your's?

Dave

[Gwhite]

Mine is an EVO, bought last November, along with one for my wife. I've had to adjust my ejector too to keep cases from bouncing off the slide rail or top cover. I've been working with the importer, and I got to examine a bunch of extractors from a total of about 8 slides. My wife's (which is 100% reliable) and the others that worked well all look a bit like this:

The key is to blunt the tip as much as possible, without having the front edge run into the back of the extractor slot in the barrel. I also added a shim behind mine to reduce the gap between the back of the extractor hook and the case rim. When you blunt the tip, you also have to stone down the "throat" of the extractor so it still swings in far enough to grab a case.

I've done this on three different extractors, mine & two for other owners (without shims, but they started with a relatively small gap). They all work very reliably. I wrote up what I did & the importer has forwarded it to Italy, but I need to send them an update. I have no idea if MatchGuns will try this approach. It's very different from any other extractor I've ever seen. The MG2 has the ejector hitting the case WAY inboard of what is conventional. I think the short "moment arm" of where the ejector hits makes this help. If nothing else, it helps control the case a bit better than a conventional sharp extractor. The other advantage is that the tip is very rugged. They make the extractors so hard they tend to be brittle, and I've had the tip chip on a couple sharp ones.

[Dcforman]

Thanks for the detailed write-up! All makes sense, except I can't quite visualize where you installed the shim. At any rate, you've given me something to check. I too have a new one. Working on the ejector fixed feeding issues I had, but I still occasionally have a stovepipe. My bullet Insert lever just broke, so I get to replace that this weekend. I've heard it's a fun job :) Despite the issues, I still love the pistol. Best 22 trigger out there.

Dave

[Ricardo]

I have a further question about Matchguns out of battery: I just got an MG2 and MG4, and since I shoot left-handed I wonder if an out-of-battery discharge might be a bit more dangerous for me. Just based on the direction of case ejection, but I expect no, since the flash would come out both sides of the ejection window, so left = right, but thought I'd get an experienced opinion.

[Gwhite]

While I was having extractor issues, I had 3 or 4 FOOB's (Fire Out Of Battery). It seemed to squirt the flames & debris out to the sides pretty well. No damage to me or the pistol. I didn't even feel anything on my hand. I think the width of the slide face helps to protect the shooter a bit. The structure is pretty symmetrical, so I don't think a lefty would be in any more peril.

I've refined my extractor shim construction a bit. I had been folding them around an old extractor, which made the corners sharp, and it was cracking the metal ("half hard" stainless). I kept finding the sides broken off & floating around inside my pistol :(

I made a slightly thicker tool to bend them around, with a bit of a radius on the edges so as not to crack the corners. So far so good....

The shim goes underneath (in front of) the rear tab on the extractor to move the extractor back & reduce the gap. I hope that makes sense.

The ejector is also definitely part of the puzzle. I put black magic marker on the slide rail and the underside of the slide cover to see where the cases were hitting. You can tell if they are getting tossed too high or too low that way. They you just have to adjust the height of the contact point on the ejector to steer the cases out the side without hitting anything. If your extractor isn't doing a good job, it will hit both too high and too low. Once they are all going the same direction, then you can work on the ejector.

[-TT-]

The shim goes underneath (in front of) the rear tab on the extractor to move the extractor back & reduce the gap. I hope that makes sense.

Only a little - I had this badly focused shot in a folder to which I added a highlight - "Here?"

[Gwhite]

That's a Benelli extractor. The thread had gotten derailed a bit talking about MatchGun extractors.

In theory, you could do the same thing with a Benelli extractor. The catch is that it's a square peg in a round hole, and if you use anything but a very thin shim, it won't fit. I'm also not sure how you could guarantee the shim would stay put when you pop it in place. You might be able to glue it to the front of the "peg" long enough to get it installed.

I've found the gap under the extractor on Benellis to be generally about right. It gets complicated, because the pocket on the bolt face isn't the full rim thickness like on most pistols. Benellis tend to run around 0.035" deep. The thickness of a .22 rim is around 0.042", so even if the extractor had no excess slop at all, there would be about a 0.007" gap. To see if you have a problem, you need to:

1) Measure the depth of the rim pocket on the bolt face. You can use the depth rod on a dial/digital caliper to check that.

2) Measure the gap between the back of the extractor and the bolt face with a feeler gauge. That will typically be around 0.015".

You want the sum of those two numbers to be somewhere between 0.048" and 0.052". I checked my notes, and on three different well behaved Benellis, it was 0.049" on all three. Over time, the front corners of an extractor can wear, and the gap will grow, but it's very rare to have a problem. Given the scarcity of new extractors, one option might be to use a prick punch to expand the metal a bit along the corners where it seats in the hole to move it back a tiny bit.

MatchGuns are very different in this area. They've changed the length of the extractors at least once, and they haven't had very good control on how deep they cut notch the back hook sits in. The depth of the pocket on the bolt face is usually just about perfect (0.042"), but I've measured gaps under the extractor as large as 0.014". That's more than enough for a case to flop around & cause ejection problems.

[-TT-]

Ah, NOT the Benelli. Never mind!