I was wondering if anyone has had the action threads on their cz55o re-cut to a non metric pitch?

I have a few of these actions and was going to have a couple re-barreled, squared up, polished etc....
So I ws thinking why not just have the threads re-cut at the same time. Other than the obvious cost
what are the positives & negatives?

Is there enough "meat" in the action walls to maintain action strength & integrity? Other potential problems?

btw - some cz's have been reported as having misaligned threads.....which is part of why I asked.

As I understand it D'Arcy, Dave Miller and others do this sort of modification as a "stardard" practice for their rifles.

Best Regards,
Dave

I have to ask, as long as they are straight, why?

Metric threads are easy to cut on a lathe. What would be the advantage to altering the CZ threads to non metric?

I guess I should have worded things differently.

Only recut if they are not straight as there would be no reason to do so otherwise...

My question remains. If they have to be recut what issues if any could I run into?

Best,
Dave

the major is about 1.1" (i for got the mm)so, if you recut, the minor would have to be a least that large .. put your calipers on the outside of the action, and ask yourself.. do you want a 65K psi bomb next to your face with the walls that thin?

So are you going to recut the action to a new thread too? That only works if you are going bigger in both major and minor diameters of the threads,
and you have to go way bigger to wipe out the pitch from meteric to SAE or whatever.
Then you have to cut the entire threaded portion of the barrel off and rethread to the bigger thread.
There is not enough shank to spare on any of the CZs I have.

I had a Dakota 76 action bought from Brownells.
The threads were boogered as it came from Brownells and all that Dakota could do was to rethread the action to the bigger Nesika Bay threads,
and charge me $200 plus shipping, for my pleasure in having the action threads re-cut.

Yep, that meant that the barrel then had to be whacked off and rethreaded.
Luckily there was enough shank left on the custom barrel for a featherweight contour, but after that was done,
it got rebarreled anyway, from scratch, with a great, fat, long-shanked barrel +4" of cylindrical knoxform.

From your question, I do not think you are a gunsmith.
Ask your gunsmith if the barrel threads are beyond help with action truing and thread chasing.
If so, and you want nonmetric threads,
rethread the action and get a new barrel to your heart's content on the threading.

quote:

From your question, I do not think you are a gunsmith.

HA...You got that right!

quote:

So are you going to recut the action to a new thread too? That only works if you are going bigger in both major and minor diameters of the threads, and you have to go way bigger to wipe out the pitch from meteric to SAE or whatever.

Ask your gunsmith if the barrel threads are beyond help with action truing and thread chasing.
If so, and you want nonmetric threads, rethread the action and get a new barrel to your heart's content on the threading.

Thats the info I was looking for.

Yes, I was refering to the action threads [not the barrel] being recut for the fitting of a brand new barrel.

Hopefully things are not amiss in this regard. Just trying to figure out what sort of options I have if problems arise.


Best,
Dave

I see you have rewrittten your original "questions" and they are good ones now.
I will defer to real gunsmiths on the answers.

quote:

Originally posted by RIP:
............
I had a Dakota 76 action bought from Brownells.
The threads were boogered as it came from Brownells and all that Dakota could do was to rethread the action to the bigger Nesika Bay threads,
and charge me $200 plus shipping, for my pleasure in having the action threads re-cut.......

So they sold you junk parts and charged you to fix it?

I believe that when D'arcy and Miller "recut" the threads they are merely chasing the threads to straighten them. Not removing the existing threads and recutting from scratch. This would still mean an increase in pitch diameter but not nearly as bad as stepping up to the next thread size.

And if Dakota charged to fix their junk you got ripped. I'd have sent it back to Brownell's and demanded a replacement or a refund. They have no right to charge to fix something they screwed up to begin with.

That's why they call me Rip.

If their is something wrong with the threads from the factory CZ should (and probably will) replace the action.

You can chase the threads to straighten them out to a certain extent or you can cut out a portion of the "bad" threads, any amount up to full major ID and recut...it depends on how good the machine and machinist is.

AS LONG AS YOU ARE REPLACING THE BARREL and cut the barrel threads to fit the resultant receiver threads.

Basically all you're doing is swapping the metal around...taking out some metal on the receiver and putting it back on the barrel shank.

Most of the Marlin levergunsmiths do this when the recut the threads for doing 45 and 50 Alaskan rebore/rebarrels.

The strength is more in the barrel than in the receiver...although the receiver does add it's bit, you could think of it as nothing but something to keep the barrel in line with the sights...or vice versa.

If you don't believe this take a look at the newer aluminum framed Brownings...the receiver just holds the barrel in line with the bolt and holds the sights on. I keep looking at my BLR with amazement...time for a paradigm shift.

You want miss-aligned threads...take a look a Remingtons...or Rugers...or Winchesters...not really a worry unless you are trying to make a silk purse out of a sow ear...as far as "normal" accuracy is concerned and even into the quarter inch bugholers.

I've had Rems that shot bugholes with the right load and I didn't know the threads were out of whack until I took off a worn out barrel, THEN found out the threads were totally screwed, pun intended.

Where you want the "trueness" is on the barrel shoulder, the receiver face, the lug abutments, the bolt face and have the barrel bore line and receiver/bolt line in alignment and if those points are " square, plumb and parallel" you will have a great shooting rifle.

Give the actions to a reputable gunsmith, use a known "excellent shooting" barrel, tell him what you expect in the accuracy department and to "blueprint" the receiver/barrel, then let him do his work.

Luck