The Technoid Examines Sub-Gauge Sporting Guns…..
The Technoid has not been so excited since he got sunburned watching his first solar calculator recharge. Sub-gauge sporting guns offer an entirely new field of experimentation! Nothing out there is perfectly suited. Any sub-gauge solution you come up with is subject to compromise and requires detailed tedious analysis. The Technoid is in his heaven.
There are two basic approaches to take with a small gauge sporting shotgun: enjoy an attractive little out-of-the-box field gun that is fun to shoot, or go whole hog and try to duplicate your usual competition gun in sub-gauge. Miss Manners would take the former approach, the Technoid will revel in the latter. If the high tech goal is to create a sub-gauge gun that is the mirror image of your standard gun, there are a number of approaches you might consider:
1) Put light sub-gauge tubes in your standard gun. Briley makes an excellent 3 gauge screw choke set weighing 10+ oz for about $1500. Advantage: good performance, medium price, gun remains familiar. Disadvantage: 10 additional ounces up front may drastically change the way the gun feels and swings. Adding weight to the back will not really return the proper dynamics.
2) Buy a four barrel skeet set and add screw chokes as necessary. Advantage: good balance, all gauges on a single familiar frame. Disadvantage: cost, barrel length (most skeet barrel sets are a maximum of 28″), barrel width (thus sight picture) differs slightly.
3) Buy a set of “carrier” barrels and tubes for your current gun. The overbored carrier barrels with gauge tubes installed should weigh the same as your standard barrels. Krieghoff offers this solution and it works very well indeed. Kolar will also make a carrier barrel/tube set for your gun. Advantage: the best way to go for familiarity, balance and performance. Disadvantage: high cost (tubes plus special barrel), availability (other manufacturers do not yet offer this solution).
4) Tube the Browning B325 30″ 20 ga (or the neat new Ruger 30″ 20 ga. if you can find one) with 28 and .410 tubes. You might want to add a touch of lead to the rear. The gun will come in around 7 1/2# to 7 3/4#. Advantage: nice balance, weight and length. Disadvantage: cost (new gun and tubes), different feel from standard 12 ga. The tubeless 20 ga would be lighter than the tubed 28 and .410.
5) The final option is the Technoid’s Grand Master of the Sub-Gauge World Solution. It has all the elements of a great project. It is immoderately expensive, technically challenging and has uncertain results. How can you resist? Here it is:
“Make” your own set of carrier barrels! Have an extra set of barrels fit to your gun and back bore them until you remove metal to equal the weight of a set of tubes. Barrel steel weighs approximately 4.5370369 ounces per cubic inch. A radical backboring from .725″ to .765″ on a 30″ O/U would lower barrel weight by 11.75 ounces, about the weight of Briley tubes. Note: A fly in the ointment is that Briley says that tubing a heavily overbored gun will require special aluminum weighing about 2 oz more. Advantage: applies to many brands of guns, weight and balance are unchanged. Disadvantage: voids warranty, may ruin gun if barrels not thick enough or perfectly concentric (few are), probably unsafe to shoot in 12 gauge, technically demanding and complicated.
Remember the Technoid’s dictum: “Complexity is the father of complication. It can also be a mother.”