In my youth, I owned both a Model 39A in the rifle as well as the Model 39A "Mountie" (a much shorter 39A rifle with a straight stock, no pistol grip). I just bought a Model 453 CZ "varmint" model with a heavy barrel and a single-set trigger last year (50 years later). In the meantime, I've owned and used a Ruger 10/22 semi-auto .22 L.R. rimfire as my primary squirrel rifle... and while it's an excellent "HUNTING" (squirrel & cotton-tail) rifle, it's not nearly as accurate as I like a rifle to be.
I don't know if the new 39A's are of the same high quality (and I very much doubt that they are) as the two Marlin 39A's I owned 'way back in the late 1950s and early 1960s. The original Marlin 39A rifle (the longer one) was EXTREMELY accurate (but I never tried it off a bench-rest)... or at least it was "extremely accurate" as far as I was concerned since I use to get "the good apples" at the top of the apple trees in a farmer's orchard (by shooting the apple's stem in half with the 39A rifle-not the Mountie which wasn't as accurate) which was located at the end of my often "long, hot, sweaty summer trek" down an abandoned railroad track out in the boondocks along which I went to shoot "varmints" with the old, longer 39A in .22 rimfire.
The farmer's apple orchard & the sweet, juicy apples at the tops of his apple trees were my "reward" at the end of the half-way point in the "trek". There's nothing like a couple or three fat, juicy red apples to quench a fella's thirst that built-up from a 3 mile "walk" along some hot ol' railroad tracks in the hot summer sun... especially when the "return 3-mile trip" down the R.R. tracks back to the car was coming up.
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The "Mountie" was never as accurate at the longer-barreled standard 39A... nor was the action on the Mountie as smooth and "velvety" as the action on the longer 39A, but it LOOKED more like a Model 94 Winchester .30/30 and that pleased me to no end!
The Model 452/453 CZ has made a reputation for itself as being an extremely accurate rifle right out of the box. Being the "accuracy nut" that I am, I bought a Model 453 (actually the same rifle as a Model 452, but with the addition of a single set trigger) in the heavy-barreled "varmint" model (sans iron sights) to get that "extra" accuracy a heavy barrel often gives plus the added "light" trigger of the single set trigger.
Then, to add to the already fine accuracy, I had my gunsmith pillar-bed the action screws and "bed" the action... and, at this time, I'm in the middle of weighing the 29 different boxes of cartridges and measuring the thickness of the rims of the cartridges and separating them into like categories to also improve their accuracy when shooting the 5-shot groups.
My goal is to be able to shoot relatively tight groups with the
CHEAPEST possible .22 rimfire ammo... and so far, the CCI Blazer SEEMS to be the most accurate of all 29 difference types and brands of .22 rimfire cartridges I've tried. And the Blazer ammo is the least expensive of any ammo I've found... costing $1.40 per 50 round box if bought by the case (I get them wholesale through my son's store).
The next least expensive .22 rimfire ammo I've found that is truly "accurate" is Federal's American Eagle brand .22 rimfire ammo (both the CCI & Federal are high-velocity, 40 gr. solid point ammo) at $1.52 per box if bought by the case (100 boxes of 50 rounds each or a total of 5,000 rounds).
Of course, neither of these "cheapie" .22 high-velocity long rifle cartridges will shoot as accurately as Wolf Match/Target ammo, but then... they don't cost 10¢ a shot like the Wolf M/T ammo does (wholesale), either! Generally, I can keep all 5 shots of the "cheap ammo groups" well inside a small, bright orange target paster at 50 yards. I believe ANY decent rifle shot could do the same... so that's no big deal.
Incidentally, I use the excellent and very clear Bushnell "Legend" (about $200 on the net, retails at $375 + tax or so) 4-12x by 40mm A/O scope on the CZ which gives a VERY sharp image and yields plenty of light (it gathers 91% of the available light). I shoot it exclusively at 50 yards (so far) off a bench-rest at the local rifle range... thus the "need" for an
Adjustable
Objective (A/O) front turret to "adjust-out" the scope's parallax which ALL big game scopes have at 50 yards.
Generally, the trigger on the CZ models MUST have some "attention" in order to get them as smooth and light as one likes... but both the triggers are user-adjustable and both the regular trigger and the single set trigger on the Model 453 are user-adjustable. In fact, you don't even have to take the action out of the stock to adjust the single set trigger. The adjustment screw is just inside the front of the rifle's trigger guard.
Once you get it all set up and the trigger "smoothed up" and the barrel "broken-in", you'd be quite pleased with the excellent accuracy you'd get from the hammer-forged CZ's barrel.
Mostly, it depends on what YOU "like"... or how you intend to use the rifle! For extreme accuracy, choose the CZ. For versatility, choose the Marlin.
The standard Marlin's under-barrel tubular magazine holds about 15 L.R. rounds vs. a 5-shot clip for the CZ. CZ has a 10 shot clip available at an extra charge.
Good luck...
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Strength & Honor...
Ron T.