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CZ LONG ARMS => CZF RIMFIRES => Topic started by: Wiley Coyote on May 29, 2018, 08:15:10 PM

Title: My CZ-452 Grand Finale - I Need HELP
Post by: Wiley Coyote on May 29, 2018, 08:15:10 PM
A week and a half back I received a beautiful CZ-452 Grand Finale. (Rifle's a .22 LR, I know because it says so.) I posted a thread about it. I even managed to find an earlier GLOSS Leupold Vari X 3-9 E.F.R. Life has been good. Then today I got the scope, mounted it, and got ready to bore sight it with my old Bushnell unit for a Range trip in the next day or two. Amazing as it may sound, my .22-.270 Arbor for the Bore Sight will NOT even begin to fit into the muzzle. And yet it drops freely into all the other .22 LRs I have. My Dial Calipers don't fit well enough to give me dimensions I can trust. FWIW, the rifle does easily chamber & extract .22 Mini-Mag 40 gr CPRNs.

I do know the bore's larger than the .17 HMR, but can't tell about a .204 Ruger? All I know is I can't bore sight it with what I have. I'm at a loss. Temptation is to chamber a round, walk out in the back yard and squeeze it off!

Anyone else encounter anything similar? Am I being overly apprehensive? Does CZ actually use such a tight bore? I need help, it's gonna be a looong night.
Title: Re: My CZ-452 Grand Finale - I Need HELP
Post by: DWARREN on May 29, 2018, 09:08:22 PM
CZ.22lr rifles seem to have a tighter bore than many other .22lr  chambered rifles.
Title: Re: My CZ-452 Grand Finale - I Need HELP
Post by: Koikeeper67 on May 29, 2018, 11:45:37 PM
CZ rifles have a very tight bore. With my 452 American most of my .22 cleaning rods will not fit and the ones that do scrub the sides all the way down the bore. I did manage to get my calipers in the muzzel and vot measurements of
0.2005-0.2105 it is hard to hold the calipers and the rifle and look down the bore to see if I was on the lands or not.
Title: Re: My CZ-452 Grand Finale - I Need HELP
Post by: eaglemountainman on May 29, 2018, 11:50:15 PM
Bore sight it the old fashioned way. At 25 yds, put it in a solid rest, remove the bolt and look down the bore from the breech. Center your target in the bore then, without touching or moving the firearm, look through the scope. Make windage and elevation changes on the scope so that it lines up as close as possible with what you see through the bore. That should get you on paper. Reinsert the bolt and fine tune your scope with live ammo. Never owned a bore sighter. I do all my bolt guns this way.
Title: Re: My CZ-452 Grand Finale - I Need HELP
Post by: Wiley Coyote on May 30, 2018, 04:44:06 AM
? measurements of 0.2005-0.2105 ...

0.2005 - 0.2008 are the measurements I'm getting.

Thanks for the comments guys. They're appreciated. Talking with others I'm finding out CZ tight bores are common. I just never encountered this before and it's made me wonder. I've got it bore sighted and ready to go to the range tomorrow. I'll have a good day with it I'm sure. Can't wait for Squirrel Season this Fall.
Title: Re: My CZ-452 Grand Finale - I Need HELP
Post by: Jiva on May 30, 2018, 10:04:57 AM
FWIW, I have no trouble with my .22 cleaning rod in my 452 - Then again, I shoot Geco for bolt action, like Frank says "keep it greasy so it goes down easy" 8)
Title: Re: My CZ-452 Grand Finale - I Need HELP
Post by: eaglemountainman on May 30, 2018, 11:21:46 AM
I use a .20 cal. Dewey rod in my Cz 22's. His .17 cal rod works well for .22 cal. also, in case you have a 455 with the extra barrel.
Title: Re: My CZ-452 Grand Finale - I Need HELP
Post by: Wiley Coyote on May 30, 2018, 12:22:08 PM
Got an email to Ivy for a .20 Cal rod in the works.
Title: Re: My CZ-452 Grand Finale - I Need HELP
Post by: Blackwatch on May 30, 2018, 11:17:59 PM
I use a .17 rod specifically for my 455 ...the OTIS small breech .22 bore brush is a direct fit (5x40 thread)
Title: Re: My CZ-452 Grand Finale - I Need HELP
Post by: dale5150 on March 14, 2019, 01:36:29 PM
I too use a 17 rod.
Title: Re: My CZ-452 Grand Finale - I Need HELP
Post by: Wiley Coyote on March 15, 2019, 08:33:17 AM
Got an email to Ivy for a .20 Cal rod in the works.

Don't know what happened with Ivy, but nothing positive ever materialized with them. Opted for Pro Shot .20 caliber rods and they work well. I did put a slight bevel on the leading edge of the 5-40 x 8-32 adapters to insure a clean entry to the chamber.
Title: Re: My CZ-452 Grand Finale - I Need HELP
Post by: Mister .22 on July 19, 2023, 05:13:09 PM
First of all, congrats on the GF, that's awesome (now that's what I call a GREAT friend!)!! I hate to dredge up an old thread, but I gots to know...

@Wiley Coyote & @Koikeeper67, I have recently picked up a Grand Finale (that has fantastic wood!) and just read this post. I have a machinist background, and ended my career as a CMM programmer. I am familiar with all measuring equipment and for the life of me, I can't figure out how you measured the bore of the rifles down to .0001" with calipers!! I can maybe see a half thou, but 1 tenth increments... I dunno!!
Title: Re: My CZ-452 Grand Finale - I Need HELP
Post by: eastman on July 22, 2023, 07:18:17 PM
part of the key to the accuracy of CZ .22 LR rifles is the extra tight bore

instead of the usual 0.222", it is a lot closer to 0.215"
Title: Re: My CZ-452 Grand Finale - I Need HELP
Post by: Fasteddie01 on July 25, 2023, 10:39:04 AM
Mr22 - They're saying  "xxx to xxx" so nothing consistent.  Prob using the $20 digital (like I do).  I ignore the 'ten-thou' readings since I'm not "playing for money".   + / -  one thou is good enuf for me.
And for a rod I use an Amazon $15 .22-cal ALL-BRASS 3-PIECE which I connected and polished the joints.  I leave it assembled in my shop.  And another for my range bag.  measures ca 0.185" - ish.  Fits thru my CZ455 & 457 V-MTR - does not drag inside the bore but is snug.