New Baikal MP-46M air pistol impressions



Author Topic: New Baikal MP-46M air pistol impressions  (Read 1019 times))

Offline subscriber

  • Sharp Shooter
  • ****
  • Posts: 896
  • yes
Re: New Baikal MP-46M air pistol impressions
« Reply #40 on: January 10, 2019, 02:09:12 AM »
"trying to hard" and "don't aim too long or insist on perfection" hits it on the head.

The third paragraph of this article states it perfectly. Read the entire article however as there is much more to it.

http://www.usashooting.org/library/Instructional/Rifle/rifle_march_april_2009.pdf

Add to that, those 50 offhand shots on paper were preceded by another 50.  So cumulative fatigue for this old geezer was also a factor.   I mean, the five shots I just showed you were shot fresh, by just going "through the motions".  No fatigue there...
« Last Edit: January 10, 2019, 08:12:44 AM by subscriber »
  • USA

Offline Stinger177

  • I think it's only at death that a guy goes from "Gotta have that" to "Don't need it".
  • Sharp Shooter
  • ****
  • Posts: 995
  • yes
  • Real Name: Dennis
Re: New Baikal MP-46M air pistol impressions
« Reply #41 on: January 10, 2019, 08:41:02 PM »
Quote
I should make an effort to stick the targets more tightly to a fresh cardboard backing, so that the individual holes are clearer.

Peter, I just remembered something I wanted to mention. What I use as a target backer is something called Ram Board. It's used on construction sites to protect new floors. You can get a 3 ft. x 50 ft. roll from HD for $30 (or steal some from a construction site, not that I would know anything about that  ;)). I spray the backside of the target with 3M Spray 77 adhesive, wait a few seconds and then stick it to the Ram Board. Be careful if you use the Spray 77 as it gets on everything (mostly your arm hairs)! The Ram Board is perfect for making nice round holes. Only real issue is that the Ram Board wants to stay curled. You can moisten the concave face and press it flat until it dries. I put mine in a pellet trap so that's not an issue for me.

I did the math and you can get 211 pcs. 8-1/2 x 11" out of a 50' roll.

Just a suggestion.  :D







Sample target using above method.



  • Denver, Colorado, USA, North America, Earth, Sol, Milky Way
You can view my gun list Here

Offline subscriber

  • Sharp Shooter
  • ****
  • Posts: 896
  • yes
Re: New Baikal MP-46M air pistol impressions
« Reply #42 on: January 13, 2019, 01:29:52 AM »
I was feeling "robbed" that my 46M was only shooting at 400 to 430 FPS, rather than the rated 500 FPS.  So, I decided to increase it compression ratio, by utilizing the piston stroke "TDC" adjustment mechanism.

The forward most position of the piston in the compression cylinder is adjustable in 4 increments per rev on the 1 mm pitch thread.  This is a factory adjustment, but can be repeated to compensate for linkage pivot wear, or to detune the pistol.

First, I decided to shoot some other pellets that are close to 7 grain (the assumed pellet to achieve 500 FPS):  The 7 grain Meisterkugeln I have, shoot at only 390 FPS out of my 46M, but seem "slow" in every platform.    This, while 8.2 grain Meisterkugeln shoot at 430 FPS, and 10.34 JSB domes at 400 FPS, out of this SSP pistol.

I have some HN Excite 7.4 grain wadcutter in unopened cans.  On shooting them over the crony, I discovered that they behaved much better, at 465 FPS.  However, this is still not "fast enough" to convince me that my 46M was shooting up to par.

I went looking for info on taking the pistol apart to access the piston stroke position adjuster.  The most useful was a slideshow in exe format.  Now, I am normally leery about clicking on any free exe, but the file opened fine.  I wanted to share this "how to guide" with you, but can't remember or find which site I got it from.  So, as GTA does not allow such large files, or exe format attachment, I copied, compressed and attached each image; and posted it to this thread as a separate entity:  https://www.gatewaytoairguns.org/GTA/index.php?topic=153388.msg155687765#msg155687765

The red arrow in the image below shows the locking screw and the four increments per rev on this 1 mm pitch thread.

I figured that shifting the piston's TDC position by one increment might not be enough, so I tried two; or 0.5 mm more air compression.  The result was that the HN 7.4 grain wadcutters now shoot at 495 FPS.  This is close enough to 500 FPS with 7 grain pellets :)

Now, I noticed that closing the cocking lever with the valve open has it come to a cushioned stop, with the lever about an inch from the parallel to the air tube rest state, when locked closed.  Pushing the lever closed then takes about 5 lb on the lever (much more at the piston), indicating that the seal is running into the end of the cylinder and being compressed. 

As this may damage the seal and actually make it leak in the future, I think I will back off the adjustment by one click.  That way, the piston TDC would be 0.25 mm closer to the end of the cylinder from "out of the box"; rather than 0.5 mm further, with obvious interference.  If I can get the piston seal to just meet the end of the cylinder, I may not lose any velocity...

Other pellets also gained around 30 FPS.  If this seems like "nothing", consider that it represents a 20+% increase in FPE...

Anyway; once you have the pistol stripped this far, it becomes apparent that it really is beautifully simple in design and construction; and quite easy to work on.
« Last Edit: January 13, 2019, 11:01:31 PM by subscriber »
  • USA

Offline subscriber

  • Sharp Shooter
  • ****
  • Posts: 896
  • yes
Re: New Baikal MP-46M air pistol impressions
« Reply #43 on: January 15, 2019, 01:14:53 AM »
I wanted to study the dynamics of this  pistol's SSP cocking linkages.  So, I modeled the mechanism in Solidworks: 
https://www.gatewaytoairguns.org/GTA/index.php?topic=153475.msg155688851#msg155688851


Then; I stretched this pistol design into a rifle concept, and modified it so that the barrel is the cocking lever, here:
https://www.gatewaytoairguns.org/GTA/index.php?topic=153749.msg155692324#msg155692324
« Last Edit: January 21, 2019, 09:15:00 AM by subscriber »
  • USA

Offline subscriber

  • Sharp Shooter
  • ****
  • Posts: 896
  • yes
Re: New Baikal MP-46M air pistol impressions
« Reply #44 on: January 16, 2019, 07:50:25 AM »
Did more detailed analysis  and came to this conclusion:

The Baikal MP-46M's pumping sliding follower generates force multiplication geometry, that very nearly follows the inverse of the air pressure build-up, that would occur when its 49 CC air is compressed into (an assumed) 0.5 CC residual volume. 

The link at the above quote will take you to all the good images, data and charts...
  • USA

Offline Yogi

  • GTA Senior Contributor
  • ******
  • Posts: 2595
  • yes
  • Real Name: Yogi
Re: New Baikal MP-46M air pistol impressions
« Reply #45 on: January 19, 2019, 02:00:36 AM »
Guys beautiful work.  To me the grip just has to hang the pistol at the end of your locked elbow when shooting one handed.  Palm shelves that really grip the bottom of your hand is what works for me.
Shooting 2 handed, you can stabilize with the off hand so grips aren't quite as important. ;)

-Y
  • San Francisco, CA
Hatsan 95 Vortex, .22
RWS 6G, .177
RWS LP8 Magnum, .177
Diana 340 N-Tec, .22 Compact Lexus
HW 50S, .177 and/or .22

Offline theanalogman

  • Shooter
  • *
  • Posts: 38
  • yes
  • Real Name: John
Re: New Baikal MP-46M air pistol impressions
« Reply #46 on: January 23, 2019, 09:12:42 PM »
Late to the game! All I can say now is after shooting my IZH 53, then my HW40, then my IZH 46M (using the right handed grip in my left hand, as I'm a lefty waiting for new grips) I'm stunned. The IZH 46M is spectacular!
« Last Edit: January 24, 2019, 05:42:22 PM by theanalogman »
  • USA  GA Ringgold

Offline Stinger177

  • I think it's only at death that a guy goes from "Gotta have that" to "Don't need it".
  • Sharp Shooter
  • ****
  • Posts: 995
  • yes
  • Real Name: Dennis
Re: New Baikal MP-46M air pistol impressions
« Reply #47 on: January 23, 2019, 09:40:30 PM »
I think you mean 46M?
  • Denver, Colorado, USA, North America, Earth, Sol, Milky Way
You can view my gun list Here

Offline subscriber

  • Sharp Shooter
  • ****
  • Posts: 896
  • yes
Re: New Baikal MP-46M air pistol impressions
« Reply #48 on: January 23, 2019, 10:32:33 PM »
Spectacular and brilliant, John!
  • USA

Offline theanalogman

  • Shooter
  • *
  • Posts: 38
  • yes
  • Real Name: John
Re: New Baikal MP-46M air pistol impressions
« Reply #49 on: January 24, 2019, 05:43:06 PM »
I think you mean 46M?

You are correct as usual. I do wonder about myself sometimes. ;D
  • USA  GA Ringgold

Offline Stinger177

  • I think it's only at death that a guy goes from "Gotta have that" to "Don't need it".
  • Sharp Shooter
  • ****
  • Posts: 995
  • yes
  • Real Name: Dennis
Re: New Baikal MP-46M air pistol impressions
« Reply #50 on: January 24, 2019, 06:01:19 PM »
I think you mean 46M?

You are correct as usual. I do wonder about myself sometimes. ;D

I wouldn't say "as usual". Just today in another thread I confused my D34 for HW30's. Hurriedly went and edited before I exposed just how old I really am getting.   ::)
  • Denver, Colorado, USA, North America, Earth, Sol, Milky Way
You can view my gun list Here

GTA - The best place for discussion about Air Guns.
 

Sponsored Ad: