Sharing some data and experience...
Congratulation
Bigugly, this is a great rifle.
This is a well traveled road and there are gezillion of threads about the CZ550. It has its lovers... and its detractors...
Do not be too worried about its detractors. As with many other things, there are a lot of folks very adamant about opinions developed through internet copy/paste and without having ever handled a CZ let alone dissected one or shot one... In truth, CZ has actively contributed to their own detraction when they quit deburring the parts, and providing a modicum of polishing to the feeding rails and ramp. Many have rightfully lamented the drop in out-of-the-box readiness when the branding shifted from Brno ZKK to CZ after the collapse of the iron curtain, but those who know and understand the rifle still appreciate that the fundamentals are all here.
Bottom line: the true magnum length, double square bridge, steel bottom, belly drop high capacity magazine, CRF
action is one of the best in the world - a diamond in the rough; but the rifle tends to be a bit rough and imperfect coming from the factory; however, fixing things to make the
rifle one the best in the world is easy and cheap.
Based on owning a number of them (7x64 ZKK 601; .375 H&H ZKK 602; .270 WIN CZ 550; custom shop .300 Wby CZ 550 Magnum; .375 H&H CZ 550 Magnum; .416 Rigby CZ 550 Magnum; .458 Win CZ 550 Magnum) and working on another dozen owned by friends over the last 40 years, here are a couple pointers...
Rings
Considering that the rifle has one of the most desirable features: integral bases milled in the double square bridge, it is completely irrational to add another set of bases on the top of the existing bases !?!?!? For this rifle, the only thing needed is a pair of rings, and yes, Warnes, Talley and Alaska Arms are the top 3, but there are differences...
Warnes have the levers on the right side and the recoil lug located in the middle of the rear ring. This places the ring a little more forward on the rear bridge. Also, some people do not like the pointed top.
View attachment 445493 View attachment 445494
Alaska Arms have the levers located on the left side of the rings, and more importantly the recoil lug is not part of the ring but part of the clamp. I had a pair but because I carry the rifle under my left shoulder, barrel forward (European style) the levers dug in my side. I also found that the recoil lug on the movable clamp was less conductive to exact return to zero.
View attachment 445495
I personally ended up favoring the Talley. The levers are on the right side, the recoil lug is forward, which locates the rear ring squarely in the middle of the rear bridge; the flat top is ergonomic; and the rings are delivered with both levers and Hex bolt so the rings can be made to be either fixed or detachable.
View attachment 445496
Stock
CZ factory stocks do not use very high quality wood; it may be nice, but it is generally not dense enough (too young). Many CZ have broken their stock at the wrist. In addition, the inletting is generally extremely loose and not conductive to great accuracy. The factory stock can be bedded, but the most durable solution, and the best for Africa potential humidity and certain heat, is to replace the factory stock with a Bell & Carlson Kevlar stock with a full length aluminum bedding block.
These are $300 well spent and you can do it when budget allows. This stock will never break or split and it will never warp and cause the rifle to lose zero. By the way, the CZ "Aramid" factory stock is nothing else than ... the “American Safari” B&C stock that is a drop-in fit for the CZ 550 magnum action..
View attachment 445484
Action smoothness
Oceans of ink has been spilled about the CZ action roughness, feeding roughness, etc.
To begin with, the .375 H&H CZ are easy, because of the cartridge shape, and because most feeding issues came from either straight wall cartridges (.458 Lott), and/or shoddy conversion / re-chambering jobs (.458 Win to .458 Lott), not to mention perennially difficult cartridges such as the rebated .500 Jeffery that were already a nightmare to chamber when London makers offered them in the golden years.
This being said, there is no arguing that machining burrs will cause things to be rough.
If the owner is observant of contact points in the rifle and scratch marks on the brass, and willing to spend a few hours with the appropriate miniature files; some fine and very fine grit sandpaper; and some valve grinding compound, it is positively amazing how slick a CZ550 will become
within a few hours of TLC.
Check specifically:
- how the central edge of the follower plate binds inside the grove for the ejector blade in the underside of the bolt (solved by rounding the central edge of the follower);
- how the burrs of the ejector blade grind inside the ejector grove of the bolt (solved by deburring/polishing the ejector blade);
- how the burrs of the lower rear bridge machining grind against the bolt (solved by deburring/polishing the machining of the lower rear bridge);
- how the forward edge of the extractor collar binds inside the upper rear bridge (solved by rounding the edges of the extractor collar and polishing the inside of the rear bridge);
- how the machining burrs on the inside and lower faces of the feeding rails grind against the feeding cartridges (solved by polishing carefully - but NOT removing material from - the feeding rails undersides).
- how the edges and the flats of the undersides of the front locking lugs drag on the action rails (solved by polishing the undersides of the locking lugs - but NOT touching the rear locking surfaces of the locking lugs).
There never was any "magic" in Rigby of London turning the $1,000 CZ 550 barreled actions into their $15,000 rifles for the decades when the original Mauser magnum action was out of production between the 1950's and the 1990's; they simply spent hours polishing and smoothing them. A caring owner can do exactly the same...
The one upgrade really needed...
The CZ comes from the factory with an action-mounted safety that blocks the sear. This is not the best safety. In a hard fall, the cocking piece of the bolt could conceivably jump over the sear and fire the rifle. 95+% of the ZKK 602 and CZ 550 in the field have this safety, and it is OK, but a true safety needs to be bolt-mounted and needs to mechanically block the firing pin, like the old "flag" Mauser safety did.
Replace the factory safety with a three-position, bolt-mounted, firing pin-blocking safety (the so-called "Winchester three positions safety”). It is not too expensive ($300 AHR or successor), or you can do it yourself,
but you have to know exactly what you are doing when adjusting the camming surface that pulls back the firing pin from the sear when engaging the safety. If you do not know what I am talking about, then you MUST have a qualified gunsmith do it. To me this is the ONLY mandatory upgrade on the CZ.
The following upgrades are also nice to have...
Replace the factory set trigger with a Timney direct trigger ($100). The factory trigger is not bad. I replaced them mostly because I prefer a traditional rounded trigger shape and I like the trigger to be in the back of the trigger bow, not in the center.
Have a good gunsmith solder a barrel-band front swivel stud ($100) and remove the front swivel stud from the stock (
order the B&C stock without a front stud). With a barrel mounted stud, you cannot cut your front hand on the stock forearm stud under recoil...
Have a good gunsmith weld full the bolt handle hole, and heat and straighten the bolt handle ($100). It makes it just a little more accessible.
All the above used to be part of the AHR Upgrade #1 if memory serves.
View attachment 445489View attachment 445501
CZ 550 with 1-Win 70 type bolt-mounted safety; 2-direct trigger; 3-filled & straightened bolt handle; 4-B&C stock; 5-Talley rings; 6-barrel band front swivel; and a few hours of TLC "breaking in" and "smoothing" - one of the world's best affordable DG rifles...
