the making of a very sweet IZH 61- easy to do

[neric]

 The IZH 61 is touted as "super accurate."  The trigger is the most impressive item on the stock rifle - 4 way adjustable trigger - it is fantastic, I never did anything to it.  However, based on my rested shooting experience at 10 Meter, I wouldn't have called it super accurate. Granted it is better than a smooth bore BB gun but I would have only called it 'mediocre'.  The first pic of grouping is with milk carton Crosman Wadcutters.

see first pic

The second grouping is with Gamo Match wad cutters,,,my favorite pellet for this gun.  A lot of flyers in both of these groupings.

see second pic

I was glad this rifle didn't cost more than it did as I have several mediocre pellet guns, but this one's trigger made it stand out. The advertised velocity, 500 fps, is not based on lead pellets, my actual velocities were in the mid 430's.  It's length of pull is shorter than I would like. The stock gun has a harsh firing cycle: it jumps a lot, a lot of twang and metal spring noise while cocking.  This gun is also called an 'all day shooter' but I found it to be a cool shooter; by that I mean after about 30 shots velocity drops off about 25 fps and groupings get even worse.  Let it cool down a couple of hours and it returns to its normal.

So here is the simple easy trick that will drastically improve its groupings:  move the metal spring guide which fits inside the main spring from the front of the spring to the rear.  All the rest of my springers have the spring guide in the rear of the spring.  Here is a pic of a typical piston with main spring and spring guide - in the rear.

see third pic

The result: jumps a whole lot less during the firing cycle - greatly improving the groupings.  Great groupings are my Holy Grail.   However you will loose about 26 fps in that switch.  That additional forward moving mass provides a little more velocity but causes the groupings to suffer, a lot.   Baikal wanted to make this rifle in the 500 fps range and that was how they did it, plus using plastic pellets. Loosing 26 fps in this plinker is in my mind insignificant; the resulting average velocity is around 410 fps. 

The main spring is not under a great deal of preload and an average man (me) can disassemble it by hand, although it took every ounce of strength I had. White lithium grease on the nylon base, after I got it out the first time, made the disassembly and reassembly easier, still was hard tho.  This base is not held in with drift pins like most guns I've seen - you have to rotate that base a few degrees so it will slide out, and that rotation would present a challenge if using a spring compressor.

While I had the main spring out I wanted to do all the other tips and tricks like a good cleaning,hone the cylinder, grind and polish the spring ends flat, moly lube.  I ground the main spring ends flat with a course belt on my belt sander, cooling often with water so it never got hot.

I kept thinking about all the twang, and noticing all the sloppy loose clearances of the spring guide inside the spring, and the main spring inside the compression cylinder.  So an idea came to me of using some sheeting of nylon as in vinegar and bleach bottles to take up the slack in those loose tolerances. Those bottles are easy to cut with scissors, the nylon material is really durable.  I cut one the length of the spring guide's insertion shaft (I made the circumference completely encircling the shaft) , and one for around the outside the main spring;  slid it inside the compression cylinder and the length of that sheet couldn't be any longer than the length of the compressed spring (this one did not completely encircle the spring - had to leave a slot for the cocking lever to engage).  I didn't do any gluing, they were all just friction fits.  I had taken it all apart after several hundred shots and they never walked around to become misplaced.

see fourth pic

I was completely astounded with the vast improvements of the firing cycle, no cocking noise of the spring compressing, no twang, no jumping, just a sweet sounding "thump" and most of all,,,truly 'super accurate' groupings.  This gun became the same smooth shooting experience of really fine guns I have like the TX200 and the HW30s.  I was beside myself with happiness.  Here is a pic of groupings using Crosman Wadcutters - which was not the best pellet for this gun.

see fifth pic

For a cheap springer with a fantastic trigger,,,those groupings approach my CO2 Crosman Challenger which cost about 4 times more and has a much worse trigger.  I did have one flyer with it, which I never have any flyers with my Challenger.  I had considered selling this gun but after this magical transformation,,,no no,,,it was a keeper for sure. 

But after not shooting anything for more than 2 yrs, its time to sell off my collection.  This rifle will be listed in this forum's classifieds soon.

Another easy thing to do which for me added a great deal to accuracy, is to file the nylon square front post site into a point.  I really like that site picture.

see sixth pic


Some of you are thinking, only 410 fps,,,,pretty weak.  But, 410 fps with a 7 grn pellet is still lethal for a squirrel.  Mind you, I don't hunt with this plinker and I don't recommend it, but there was one time I was out plinking with this gun,  up in a tree about 18 yds away was a squirrel barking at me.  This gun is sited for 10 meters, I never thought I would hit the squirrel at 18 yds, I just wanted to shoo him away.  Well it turns out I did hit him, pellet penetrated his spine, knocked him out of the tree,,the gun is a 5 round repeater I was able to finish  job quickly.  I wrote an article about that experience here:

http://www.gatewaytoairguns.org/GTA/index.php?topic=837.msg6038#msg6038

So with no machining requirements and only common tools and materials,,,you to can produce a REALLY fine springer plinker for not much money and it will have a truly fine trigger.  I shoot this inside my house at 10 Meters

[Tater]

Nice job making it a good shooter.

[farrlarr]

What is the basis for, "- - - Gamo Match wad cutters,,,my favorite pellet for this gun - - -"?  It seems to me that they don't shoot very well in your rifle.  If you haven't tried more than two types of pellets, which is suggested by your post, I don't think you can say much about favorite pellets for this rifle.  Trying a variety of different pellets might well show that others shoot much better in this gun.

[neric]

You are right, I should have mentioned all the rest of the pellets I tried in this rifle.  In the beginning I didn't take notes and I didn't write them all down.  Some of the pellets didn't even fit in pellet holder. There were a lot of pellets not worthy of mentioning.  I did write down the top three.  I have 10 different .177 pellets and I tried them all.

 The top three were: 1. Gammo Match  2. Crosman Wadcutters  3. RWS (don't remember the exact one).   Wadcutters rather than domes performed the best for me.  Pointed pellets were horrible.

I agree with you, the Gammo Match didn't shoot very well in the unmodified stock rifle.  The point I mentioned in the beginning of the article is that I thought this rifle was only mediocre rather than 'super accurate.'

My other point was after I had done this mod, the Crosman Wadcutters which were previously pretty bad in this stock rifle, suddenly became fantastic groupings as evidenced in picture #5.  This was proof enough for me to say that it was the rifle that was not really a good shooter from the factory, but had become a super accurate shooter.  I didn't change, I shoot from a rest for grouping evaluations, the pellets didn't change.

I didn't bother to test other pellet varieties after the mod, I was very happy with Crosman Wadcutters performance, as well as I bought several cartons of them by that point since those shoot very well in my Challenger,,,not to mention they are inexpensive.

[neric]

I also forgot to mention in the article the improvement of the extreme deviation after having done this mod.

Before the mod extreme deviation was averaging 20 fps.

After the mod, extreme deviation dropped to averaging 8 fps.   The mod was performed in Feb 2011.

A couple of days ago in preparation to sell this jewel, I got this rifle out to see how it shot.  More than 2 years of not shooting, the extreme deviation was still 8 fps.

I will list the current grouping pic and chrony numbers in the classified ad when I sell it.