What smith solutions are viable here?

P

Pond James Pond

New member
I posted a thread in the semi rifle forum about my brand new, unfired VZ58 (assembled from military spares stock and sold as a civilian semi-auto). The thread is here, complete with a picture of the problem.

The problem is that there are several places where the chrome rifling has been damaged/chipped, right below the crown.

This is not the States and just getting a new gun as a replacement is not an option, so I want to have some viable alternatives ready for the shop to increase the chances of getting this taken care of satisfactorily.

If given to a smith what are the options for tidying that muzzle so that I can get the most accuracy out of this gun as I can?

I don't think a rebarrel is likely, nor do I think a repatriation to the CZ factory is going to happen either.

So, I'm open to all suggestions that involve working on the gun as it is.
 
If we are talking only local repair options, the first thing I would do is fire it and see what accuracy its capable of. If it shoots fine let it be. If not, you can cut the barrel off just below the problem area. Looks like you would only have to cut 10mm or so, maybe a little more. Make sure you cut it square, then recrown. This is a fairly simple matter for a competent gunsmith and shouldn't be that expensive.

Of course the shroud that holds the front sight might complicate things... But you can probably pin that on a little further back. If not just cut it with the barrel.
 
Let me start off with this: I am not a gunsmith or machinist.
You might be able to get a recessed crown cut into the end of the barrel. Simply put it would be akin to taking a drill and reaming out the end of the barrel, removing the rifling back 10-20mm. Of course this would be a lot more precise operation than what could be accomplished with a drill but you get the idea. The chrome lining may eliminate this as an option. If this is a viable option I would think it to be the least invasive.
 
I responded at length to your "Chink in the armor" thread
Yes,a counterbore or "recess crown" is a very practical solution.

I would not approach it as "taking a drill and reaming" but the previous post is seeing the solution
 
Yes at this point the counter bored "crown" is going to be the best option.

A tool needs to be made with a pilot that will ride on the lands. It is going to have to be a very close fit. Probably about .0005" to .001" undersized.

On the backside of the pilot, about 3" back you'll need a cutter of about .320" in diameter.
You simply run the tool into the muzzle by hand. Keep it oiled as you turn it with genital pressure and let it cut the problem area away. I'd cut it back about .150"
 
I'll see what the shop says then suggest a counterbore if they don't come back with something encouraging/feasible.

The damage extends about 3-4 at its deepest so a 5mm counterbore should be fine, I imagine.
 
One old trick that can often cure this kind of problem is to insert a chamber reamer into the muzzle and use the throat portion of the reamer to cut away the damage. The throat cutting part of the reamer tapers away the lands in the chamber, and it will do the same thing at the muzzle.

Only take it in as far as you must to remove the damage. If the reamer has a good fitting pilot the new "crown" will be concentric.
 
A counterbore would be the least expensive option. Other than turning of the damaged bit and re-crowning. That may not work well though. The chrome might just chip more. Mind you, it might with counter boring too.
I really wouldn't worry too much about accuracy from a VZ58 though. AK's and their clones were not designed nor expected to have great accuracy.
 
Good idea,Wyo!! My question(I don't know) Its a chrome bore.A high speed steel cutter will break down pretty quick. My assumption is that might result in the chrome at the actual crown being ragged.(along with trashing the reamer)

I know essentially nothing about the OP's Estonia.I would assume there are skilled machinists and vertical mills available. I understand piloted cutters,thats typical of gunsmithing.

If I hang the barrel and upper off the side of the table,vertical and rigid (think vee block angle plate) and spin the mill turret/ram over to put the spindle over the bore,I can indicate around a pin gage in the bore.
Don't need a pilot. I can use a carbide end mill.Maybe a 3/8 ball mill,or a boring head and carbide boring bar. Etc.
With a light touch,high rpms,and use of the quill stop,a final dress could be put on the crown with a dressed mounted stone.

In other words,a plain,square carbide end mill can make the initial counterbore.Then put a mounted stone in the quill,dress it just smaller than the end mill,to clear on the OD,but cut on the lower face.

Dress a typical 11 deg angle on the bottom of the stone.Wind it up to 4000 rpm,use the quill stop to control downfeed till you just get a spark.Maybe 003 more.Then the fine edge of chrome is ground.I would not be afraid of a larger dia counterbore,like 9 mm or .375.
 
Last edited:
I know essentially nothing about the OP's Estonia.I would assume there are skilled machinists and vertical mills available. I understand piloted cutters,thats typical of gunsmithing.
Click to expand...

I'll seek out genuine gunsmiths for this job.
 
Very good question HiBC, and one for which I have no answer.


Good luck Pond.
I would help you if you were only about 4000 miles closer.
 
My guess is the rifling was damaged somehow when the anode used for the plating was removed, but that's above my pay grade...

1) Shoot it. If damage is detrimental to accuracy it could be counterbored as suggested.

2) Is a replacement barrel that tough to source there? They're $45 here:

http://www.ohioordnanceworks.com/parts/vz-58-parts

A Smith could press out the damaged barrel, and install a new one....

Option 2 would be preferable (if you can get the barrel) IMO because your value is affected by the damaged barrel whether you counterbore or not.
 
I've yet to find a place that sells barrels. It would be great if it were possible to order one from that linked site, but I think ITAR would say NO!!
 
But they end up on sale on yours! :(

There may be a place that sells them, but it is not so common for people to order replacement barrels here, especially for something like the VZ. Many EU countries don't even allow them.

I'll first eliminate counterboring 5mm of this barrel before I look at spares, though.
 
There is more damage to the barrel than just the plating. Industrial hard chrome plating is very thin. There are chunks out of the steel.
 
You must log in or register to reply here.
Back
Top