Free pistol enigma - help me

Sylouell · Post by **Sylouell** » Mon May 19, 2008 3:02 pm

I bought a used free pistol and I quickly realized I have to ajust the rear sights fully to the right to hit the target center when I shoot at 25 meter.

After the first shooting session, I inspected the pistol carefully to see if the canon was curved or misaligned with the rear sight assembly. Everything seemed normal.

I went back to the shooting range for a second shooting session. It was less windy than the first time and I managed to shoot a good match with a score of 539. Note that to shoot this match I had to place the sights in the same position as the first time (fully to the right).

I came back home and decided to take several pictures to confirm or infirm bad sight alignment. I removed the handle and set up my camera on a tripod. I took sevaral pictures of where the sights were pointing then I took a picture through the barrel without moving the pistol. The pictures were took with the sights in the same position used to shoot the match. The target is at 7 meter from the pistol. It shows that the canon is pointing at 2 cm right of where the sights are pointing.

How do you explain this phenomenom. I am an air pistol shooter and the sights of my air pistol are approximately centered. It should therefore not come from the way I am sighting. I payed attention to cant and it does not seems to be the problem. Anyway, it would require a lot of cant to produce such a deviation. Can it comes from the rifling effect, I doubt it. I start thinking I am crazy... Your help would be appreciated.

Steve Swartz · Post by **Steve Swartz** » Mon May 19, 2008 3:21 pm

Dude!

If the first picture is a picture through the bore of your pistol (lower part of picture) vs. the sights (the top part of the picture) then yoiur sights are definitely off-boreline!

Either the front sight or rear sight is the culprit.

If hte front sight is on a "dovetail" type mount, it can simply be drifted left or right to make gross corerctions.

One thing to consider- with a question- if your gun has an adjustable rear notch width; it is quite possible for the width curently being used the sights need to be re-centered.

Some guns with adjustable rear widths use a "barrel-sleeve" design where the entire sight blade moves sideways as the width is changed.

Have you disassembled the rear sight mechanism yet? What is the design of the rear sight mechanism?

Sylouell · Post by **Sylouell** » Mon May 19, 2008 8:03 pm

By the way, the pistol is a Morini CM84E. The front sight position is not adjustable, you can only change it's width. The rear sight assembly is not moveable. I have dissasembled and modified it to allow a greather lateral adjustment on the right side. It is similar to the sights you find on Morini air pistols. It remains in position when you change it's width.

The picture have been taken with the sights adjusted so the pistol shoot straight. I will try to have other people trying the pistol to confirm the problem is not behind the pistol. I would be surprised to be the source of the error as I have 2 other pistols (air and standard) that shoot straight with the sights aligned with the bore.

I will also try to build a clamp so I can check the pistol for grouping and sight adjustment clamped.

I you have any idea of what could be the source of the problem, let me know. If the pistol shoot good groups, I will simply use it with the sights in that weird position.

Steve Swartz · Post by **Steve Swartz** » Mon May 19, 2008 8:14 pm

The Morini CM 84E uses a two- barrel (opposite threaded dual inner/outer screws) system. One spindle adjusts width, the other adjusts azimuth.

[FYI while the lateral offset is minimal when changing widths, it is not zero]

As you open (close) the sights, you eventually need to "recenter" the carriage.

When I opened my Morini CM 84 E rear sight notch, I needed about 2 1/2 turns of internal-external spindle adjustment in order to recenter the carriage.

This was from the original factory settings.

If you purchased your gun used, who knows how far off your carriage is now.

Steve

Chris · Post by **Chris** » Tue May 20, 2008 12:50 am

I do not own a morini but if you can shoot a 539 in FP then I think you are on track and your sights are messed up like Steve suggests.

On my Toz I have to put a spacer under my front sight so I can have some adjustment in my rear sight and my front sight still cant's to the right. I even used a piece of plastic from a box of olimp-R.

Steve Swartz · Post by **Steve Swartz** » Tue May 20, 2008 11:47 am

Oh one more thing on the Morini-

The front actually is "adjustable"

The entire compensator/muzzle brake assembly *can* be rotated around the barrel. While not easy to do, it is possible to get the compensator "cocked" when tightening the allen bolt. From your pictures this does not appear to be the case, as the front sight blade still appears to be vertical (no "lean").

This sounds impossible but I have seen it! The allen bolt will actually stick out above the surface of the compensator (until enough force is applied to squash the nose of the bolt and/or force another dimple on the barrel itself).

Steve

Sylouell · Post by **Sylouell** » Tue May 20, 2008 2:29 pm

Mark suggested that it could come from the fact that I shoot cross-eye (left eye - right arm). The recoil force not being in the axis of my arm could cause this deviation.

Up to now, that's the most plausible explanation. I will investigate in that direction and I'll post the results in this thread.

Thanks for your support!

Sylouell · Post by **Sylouell** » Thu May 29, 2008 5:50 am

I changed back to my right eye and it does not correct the situation. I will have other experienced free pistol shooters look at and try the pistol this weekend. I hope we will be able to find an explanation.

Steve Swartz · Post by **Steve Swartz** » Thu May 29, 2008 7:32 am

Based on your pictures there is something mechanically misaligned.

The front sight appears vertical, so the shroud assembly does not appear to be offset.

That leaves the rear sight carriage, unless there is some critical missing information about the photo images.

J.Hoes · Post by **J.Hoes** » Sat May 31, 2008 5:39 pm

I bought my CM84E new, and had a bad experience with the sights. With centered sights the pistol grouped somewhere in the 3 ring at 3 oclock. (50 m, ISSF target) Grouping in bullseye was only possible with rear sight adjusted to extreme left and front sight slightly canted to the right.
The receiver is build up from two metal plates, pinned, riveted and bolted together on distance pieces. The side plates were slightly bend to the right, and that seems to me a logical cause.
I returned the pistol to the factory, where they swapped the barrel. The receiver was not touched. The repair however brought things back to normal.

Greetings Hans.

IPshooter · Post by **IPshooter** » Sat May 31, 2008 10:59 pm

J.Hoes wrote:I returned the pistol to the factory, where they swapped the barrel. The receiver was not touched. The repair however brought things back to normal.

Greetings Hans.

Hans,

Thank you for the tip. I now know why my 84E doesn't shoot all 10's. It must be the barrel. And, all the time, I thought it might be me.

I will return mine to the factory and have them fix it so that whatever I do, I get a 10.

;-)

Stan

PaulT · Post by **PaulT** » Sun Jun 01, 2008 2:39 am

Several things to try or consider
1. Morini sell offset front sight blades for the air pistol (162) the may be similar for the model 84 free pistol.
2. Stating the obvious, errors in grip or an off-set of the grip is possible.
3. If you are sure that the front sight has not “rotated” off centre, you could try a different barrel in your pistol or vice versa and observe outcome.
4. If you have adequate clamping facility, it is possible that the bore is off-set in the barrel. This as I recently discovered is not unheard of but apparently very difficult to test – swapping barrels above is a simple way of performing a crude test.

ColinC · Post by **ColinC** » Sun Jun 01, 2008 8:28 pm

OK you have me thinking now. When I first saw this post and the pictures, I just left it to the experts to sort out but it appears you are no closer to an answer.

My Morini air pistol has a similar "problem" The rear sight has to be wound right over the the right (I think 1-2 clicks) from maximum windage for me to shoot. I have always thought the problem was my eyesight (short-sighted with an astigmatism) because I have to wind it across 15 clicks for others to use it.
Having done that last week I note that the rear sight is still way off centre, overhanging on the right hand side but not the left.
Is it something peculiar to the Morini?

Further, Steve are you suggesting that when you open up the rear sight width that only one blade moves and that you then have to recentre? If so what is the process of moving the internal-external spindle?

Steve Swartz · Post by **Steve Swartz** » Sun Jun 01, 2008 9:33 pm

You need to remove the rear sight carriage, then turn the two halves around the center post simulatnaeously. Both blades will then move together in whatever direction you want. Then reassemble intot he carriage and viola like magic you are recentered.

I will dig around for a detailed description (I think David L and I discussed this about a year and a half ago; for some reason the factory guns were shiiping with uncentered carriages and it got worse as you opened the rear sights. i bought a new gun and had to go about 2 1/2 full turns on the outerdrum-inner spindle to get it synched up.)

IPshooter · Post by **IPshooter** » Sun Jun 01, 2008 10:06 pm

ColinC wrote:OK you have me thinking now. When I first saw this post and the pictures, I just left it to the experts to sort out but it appears you are no closer to an answer.

My Morini air pistol has a similar "problem" The rear sight has to be wound right over the the right (I think 1-2 clicks) from maximum windage for me to shoot. I have always thought the problem was my eyesight (short-sighted with an astigmatism) because I have to wind it across 15 clicks for others to use it.
Having done that last week I note that the rear sight is still way off centre, overhanging on the right hand side but not the left.
Is it something peculiar to the Morini?

Colin,

If it's not something peculiar to the Morini, then you and I are both weirdos. With my 162EI, I have to crank the rear sight all the way to the right to center my group. In fact, with the notch opened up to the size I like, I run out of windage and have to close the notch some just to move it far enough to the right.

Steve, I've never been brave enough to try your disassemble/re-assemble trick. It does make we wonder why the factory doesn't ship these guns with them roughly centered in the middle of the windage adjustment. Does anyone run into this problem going to the left?

Stan

David Levene · Post by **David Levene** » Mon Jun 02, 2008 1:10 am

Steve Swartz wrote:I will dig around for a detailed description (I think David L and I discussed this about a year and a half ago; for some reason the factory guns were shiiping with uncentered carriages and it got worse as you opened the rear sights.

This is the description you posted back in February 2006 Steve:-

O.K., I had to go through soem fine tuning on my new 162E. I have a 6mm front blade (barn door) and use about 1/3 the front width on either side (open barn doors) on a sub six hold (front sight on bottom edge of barn doors).

Bad eyes.

Anyhow, I first noticed that it appeared as though I could have either wide notch, or centered notch, but not both. I Feel Your Pain.

If you aren't comfortable chasing little springy bits around your house, stop now and send to Scott.

Assuming you are prepared to completely disassemble your rear sight assembly, do so now. When you get to the point where the rear notch sub assembly is "free," you will note that (oh by the way, put that spring that just went flying across the room in a Safe Place. And yeah, hope you got a real good look at exactly how it is supposed to go back in cause it's real easy to do it wrong) the two halves of the blade can be rotated along the two-threaded rod piece they are attached to. The rod is counter threaded (IIRC) so screwing them in the same direction actually moves them in tandem along the rod left-right; screwing them in opposite directions makes them either closer together or farther apart.

Hope you counted the number of clicks used when disassembling the rear sight assembly . . . this comes in real handy later so you can tell whether or not you actually amde things better before reassembling the whole danged thing to find out you actually just made it worse! As you unscrew the rear blade subassembly using the L/R adjustment screw you are creeping the two blade halves along the double-threaded rod at the same time. This gets clearer here in a paragraph or two.

Once the rear blade subassembly is free, take a moment and admire the elegance of this engineering solution. No, seriously! Cussing out the design engineers right now isn't helping. It is a quite clever piece at that.

O.K., what you are trying to do is get the blades wide apart, but way over on the left side of the rod. When you screw the rod-blades subassembly back in, you want there to be enough threads left to get the RH blade over to the RH side without running out of thread.

This is really hard to explain without your actually seeing it.

You will have to flop the left blade >>out<< (notch wider!) a few revolutions (how many is a few? wish I knew. I didn't follow the advice I'm giving you right now; I had to Find Out The Hard Way). ANyhow, I think two or three revolutions should do it . . . oops, the left blade just popped off the rod! O.K., one less than that then. Stiff upper lip now; back at it!

Anyhow, be prepared to fiddle with this several times installing/tweaking/re-installing before you get it just right.

Steve Swartz · Post by **Steve Swartz** » Mon Jun 02, 2008 7:49 am

Thanks David- and I believe the 84E is of similar design.

After re-reading my description, I confess it isn't very good at that.

Do we not have pictures of this in the TenP files?

If we can't dig anything better up, I will disassemble and re-assemble and post pictures with better description.

*After* I get back from nationals of course!

Fred Mannis · Post by **Fred Mannis** » Mon Jun 02, 2008 10:51 am

Steve,
That's the price you pay for wanting a pistol with an electronic trigger :-)

Fred

ColinC · Post by **ColinC** » Mon Jun 02, 2008 6:00 pm

Thanks Steve
I appreciate the description, having pulled a few things apart to see what makes them tick and then find it takes 5-6 assembly/reassembly processes to get the thing working again, without ever finding what made them tick in the first place, I might have to pass at this stage.
Looking forward to a more diagramatic description in the future.. Meanwhile I'll just put up with it. With my failing eyesight I'd hate to miss seeing that spring ping across the room!
Colin

Fred · Post by **Fred** » Sat Jun 14, 2008 6:37 pm

Days after reading this thread I realized there is a closely related question which I hope someone can answer. If adjusting the Morini rear sight gap either narrower or wider causes the the gap center to move, then any gap adjustment done in a match would need to be compensated with a windage adjustment immediately, so as not to lose points.

So here's the question: is there a formula? For example, does opening the gap 2 clicks mean you need to adjust windage 2 clicks right? Has anyone figured this out? Presumably since the adjustments are connected, there should be a fixed ratio.

I would appreciate any informed replies, especially related to the free pistol.

TIA,
FredB

TargetTalk

Free pistol enigma - help me

Free pistol enigma - help me

cm84e

A related question