It would only devalue it (to a collector) if you tried to sell it in England again and that's not happening any time soon. Proper barrel measurements will show whether it can be safely done whether it's an American gun or a Euro gun.

If you're currently reloading 16ga. 2 3/4", you probably have a favorite recipe.
It 's my experience, having been reloading for nearly 50 years, that there is no 2 3/4" load, that I can not duplicate in 2 1/2", with an alternate wad. I load 12-28 and have the 'short kit' on all of my MEC presses. With the exception of a great wad by Fiocchi, which has been on back order for a year, I use Guilandi wads and almost all are available in short or long (and even medium) lengths.

Thanks to all for responding. This place is a real pool of knowledge and view points.
I have gotten info from the maker in England and still have not reached an agreement but I am as interested as ever. I have decided that altering the barrels is NOT the path I would take. I Have had advise both ways about 2 3/4" in the short chambers and not sure how comfortable I'd be as to pressures. The idea of making & loading 2 1/2" shells is less intimidating and that is the path I'd go down.

Maybe this willl be considered as being too picky but, cylinder bore at the muzzles is not "choke". "Choke" is another term for constriction and, the lack of constriction constitutes an absence of choke.

I understand, and realize, that there may seem to be a lack of accepted terminology to describe this condition. But, in the end, a gun that is cylinder bore at the muzzles has NO choke.

That is what I have always understood as the definition of cylinder bore. I’ve always taken cylinder bore as an indication that barrels may have been cut on older guns. More recently I have been told that some English guns were made with extremely open chokes for use in driven hunts and that cylinder bore was not really unusual.

However, there are many examples of Parkers that were choked “cylinder” from the factory where there is actually bore constriction of up to .005” or even .007” at the muzzle. I feel certain that this was done to get an acceptable pellet count.




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I concur with you, Dean.
I have lettered Parkers with recorded cylinder bores with .004 constriction. If you define cylinder by its pattern (50%) and you need slight constriction to achieve that…

Fox Sterlingworth Skeet & Upland Game Guns (SKUGGS) are typically choked "skeet/cylinder" (a Savage Fox designation) in the right barrel, but usually measure between .004-.007" actual constriction at the muzzle, which jibes with what Dean wrote.

Sherman Bell did the research for us, finding that there is no appreciable rise in pressure when shooting 2 3/4" shells in 2 1/2" chambers. The advice from Bell and others is to shoot shells of a load that was made for the gun, regardless of the length of the hull. I have shot 2 1/2 DE, 1 ounce factory 2 3/4" 16 gauge loads in short chamber 16s for decades with no ill effects on the guns. Drilling out a short chamber gun is a waste of time and money and possibly to the detriment of the value of the gun. The Brits do so much to destroy their gun barrels by excessive honing of the bores, and I won't add to the damage by drilling out the chambers.

...or lengthening forcing cones for that matter.





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