I must admit I am a fan of the break action, and the single shot.
It probably is because my first shotgun, and rifle, were a break action Winchester Cooey .410, and a Lithgow/Slazenger 1B .22lr.
That shotgun was 'officially' my mothers, but I used from a young age (and still have it). It was an 840, and all the 840's appear to have been built on a 12G action, and then you have a breech area the same size as a 20G, then it tapers down to the end of the barrel, which is a thick .410! I learn to ignore the bead, and point, when hunting ducks, or hares (jack rabbits).
I more recently did it up, and gave it an aluminium pivot block (the plastic had broken), and drilled and tapped the barrel, to add a .44" tactical options fiber optic sight (I used the same hole, then trimmed and reversed the rifle sight). At the same time I lightly reamed, and polished, the choke, to open it up to .398" and polished the forcing cone, barrel and choke. I added a clamp on the barrel, and rear attached, for a sling.That shotgun is now 'perfect', points and shoots where it should, and breaks clays with 7.5shot, 3 inch shells, out to 40m, regularly!
If you want to carry 'extra' shells I use a 'Spika' premium sling, which lets you push shells under the nylon band, across the sling, where they present the primer end, and let you grab and insert one, as the shotgun ejects the fired case.
I use these .410 shotguns for teaching kids (and some adults), how to use a little shotgun, as an introduction, and general duty rural firearm.
I bought a later Cooey 37A .410 thinking it would be basically identical to the 840 (it is, and it isn't). It is a 'prettier' firearm, with stamped etchings, and a gold trigger. I have done it up the same way (no aluminium hinge block replacement required at this time), but found that it only needed a .365" front sight. I love the single shot Winchester Cooey design.
I have more recently 'found' the Savage 24 combination rifle/shotgun.
I have a tight action, basically unmarked, field grade series P .22lr over .410 (has the hunting scenes stamped into receiver, barrel selector on the hammer, and the front of trigger guard opening lever), which, once I shimmed the shotgun barrel (literally cut a shim from a baked been tin, shaped it by clamping it to a round tool handle and tapped it to get the curve, and then inserted into the round front shotgun barrel guide, with a brass punch, to move point of impact across) it shoots both barrels to same point of aim, it points naturally, (I had to add a correct wedge to the rear sight - someone had trimmed a hacksaw blade on an angle, as an adjuster, without knowing you need to solder two together, so they don't slip sideways), and is a pleasure to carry. It gives you options; I have yet to give the trigger the attention it requires.
I have a "camper" Savage 24C, in .22lr over 20G (cylinder bore) which, it appears, someone once did a serious disservice to, by burying it nose down. The action is that tight it appears unfired, the trigger appears reasonable. However, the very end of both barrel is seriously corroded, there are spots of corrosion elsewhere, as it appears ends of the barrel sat in water for an extended period (maybe buried in a leaking PVC tube?). I have tried to recover them, however I have just got a quote to get my local gunsmith to give them the attention they deserve. I have discovered how to regulate the barrels on my 24C, by loosening off the single screw on the barrel band, and 'moving' the barrels in relation to each other. This aligns them in the vertical, alas I have not been able to lift the 20G pint of impact! What I did discover was that (after I slimmed the far too wide front sight, and painted the face gold - it's steel), was that the .22lr barrel corresponds to the fine v of the sight, and the shotgun corresponds to the 'full' V of the overall sight. The rear sight of that 24C has been changed to a Marble sight.
I love the reliability, and simplicity, of the break action design.
The .45-70 Henry above looks like a fantastic rifle, too! (My cheese and kisses will blow a gasket, if I buy another rifle/shotgun any time soon! I may have purchsed a few different one's I always wanted, and a bit of reloading gear recently
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