I have an 11-87 Remington trap gun with .744 bore that tapers down to .728 at the final inches of the muzzle. Doesn’t that give the equivalent of a .016 restriction or “choke” without any additional device added (has factory screw-in chokes, but measurements exclude that area)?
Having reviewed this condition with a “barrel-smith,” it was suggested that the longer Beretta chokes could be installed. It wasn’t clear if the .728 constriction would or should be “opened” up before determining and selecting final choke sizes.
I really would appreciate your response.
When manufacturing guns, Remington has always taken the easy and economical route. When you are in the business of mass producing guns, cars or refrigerators, you have to cut corners at every possible turn to produce a product that can be sold for a profit.
Although I have no inside information, I am pretty sure that Remington’s early “overbore” trap gun barrels were the result of advertising hype knocking up against the realities of the bean counters in accounting.
A surprising number of shotgun “breakthroughs” are just trendy gimmicks. Now I am not saying that backboring is just a gimmick, but no one has yet proven to me that it produces improved patterns, less recoil or anything else. It may provide very slight improvements or it may not, but this isn’t the time to get into that.
Right or wrong, Remington decided that it needed a “backbored” gun to compete in the trap gun market place. The problem with producing a screw choke gun with an enlarged bore is that you have to make an entirely new series of chokes. Screw chokes that fit properly in a gun with a .728″ bore, will not fit in one with a .744″ bore. It isn’t just that the constrictions will be off. The skirt of the choke from the tight barrel may impinge on the bore of the backbored barrel. This would result in one shot per choke.
Obviously, at the time, Remington didn’t want to introduce an entirely new series of overbore chokes to go with their “backbore” barrel. They split the difference and used an overbore barrel with a solid choke. Nothing too new about that EXCEPT that they then threaded that solid choke area for screw chokes to produce a second level of choking.
What they ended up with was an overbore barrel that had about .016″ to .018″ of solid choke built into it- just like most “modified” choke barrels. Then, in front of the solid choke they further constricted it with screw chokes. The solid choke ID “just happened” to be the same ID as their normal non-overbore barrel, so the current line of chokes fit in just fine.
Of course, the chokes had to be re-labeled because the barrel was already starting out with .016″ to .018″ of choke, but Remington didn’t have to make a whole new series of larger chokes. They just relabeled a cylinder bore screw choke to read “modified” because they knew that it was already starting out with a modified solid choke before the screw choke. The “full” screw choke probably only measures about .020″ (normally a modified) because its constriction would be added to the existing solid choke.
All of this made great economic sense to the Remington accountants. Browning Japan bit the bullet early on and simply went to overbore barrels for everything and switched their Invector chokes to Invector Plus overbore chokes.
As to adding the Beretta chokes, I dunno. Have you actually patterned your Remington chokes to see if they are giving you the patterns you want? I don’t really see how retrofitting Beretta chokes is going to make the slightest difference and it will definitely open up the possibility of screwing up the barrel. If it were me, I would spend the time fine tuning the existing set of chokes and leave it at that. If you are shooting trap, fool around with choke/shell combinations until you get an 80% pattern (30″ circle at 40 yards), say “Thank You”, and go shoot. You can use a little “looser” shell at 16 yards if you insist, but 80% is a pretty realistic handicap percentage.
Shotgun Report’s Technoid
(Often in error, never in doubt.)