Choke Design And How Light Chokes Can Alter Gun Balance


Bruce,

In a barrel that has fixed chokes will the titanium chokes be lighter than Briley thin wall installation?

What would you recommend for a sporting clays/all around custom choke?

Let me clear this up a bit Teague chokes have a gradual taper and some other companies use a parallel section on the inside of the choke. If you are going to get custom chokes might as well get what works best. What do you think?

I will request 5 chokes SK,IC, Lt.Mod, Mod, FULL. The gun is a 682 GOLD trap, 32″ barrels with a weight of 1.570 kg and IM/F fixed chokes.

W.

 

Dear W,

I’m not sure that Titanium chokes are going to do anything for you. A set of Briley Thin-Walls (most appropriate for your fixed choke Beretta) simply replaces the metal removed from the choke during the threading process. When comparing a fixed Modified choke and a Thin-Wall installation with a Modified choke, there should be no weight difference because the barrels and chokes are made from just about the same weight steel.

A Briley Thin-Wall in Modified constriction from one of my FN Superposeds weighs 211.6 grains. Titanium weighs about 2/3 as much as gun steel, so the same choke made in Titanium would weigh 141 grains. That’s 71 grains weight savings per choke or 142 for two chokes. There are 437.5 grains to the ounce, so the weight savings on a pair of Ti-Chokes would be only slightly more than 1/3 oz. I don’t think that’s enough weight savings to matter and I don’t think that you would be able to tell the difference.

Where the Titanium chokes might makes sense is when you are using extended Briley over-the-counter steel chokes in an Invector Plus Citori. Those brutes, in modified constriction, weigh 666 grains. If you substitute Ti-Chokes you would save a full ounce. (666-444 x 2 = 444). You can definitely feel one ounce weight change under the front bead. If you substituted flush mount Ti-Chokes for extended steel Invector Plus chokes, the savings would be closer to 2 oz and the handling of the gun would be transformed. Two oz under the front bead is a lot.

Bottom line: for what you are thinking of doing, if weight reduction is your goal, I don’t think that Titanium chokes will make the slightest difference when compared to a standard installation of Briley Thin-Walls.

Choke design: As luck would have it, I was just corresponding with a major aftermarket choke manufacturer this morning concerning a written bit on the explanation of choke and patterning. Just about all American after-market choke makers use the classic conical/parallel design. I’ve not measured any of Nigel Teague’s excellent chokes, but I do know that pure conical chokes do work well with the more open choke designations, especially when using fine shot. There seems to be more of an issue with taper-only chokes in tight constrictions, though there are some good examples. Remember, the choke is only part of the pattern equation. Still, every high end fixed choke clays gun I’ve ever miked (Superposed, Beretta, K-80, Perazzi) has used conical/parallel chokes.

Frankly, I’d use whatever design the choke maker suggests on the assumption that he has looked into this more than you (or I) have. Screw choke makers also have different parameters than fixed choke designers. Screw choke makers have to make ALL their chokes to the same length, unless you discount the various length chokes based on constriction that Fabarm produces. Generally, the tighter the choke the longer the choke. The more open, the shorter. Screw choke makers must make them all the same length. Fixed choke makers can optimize for best performance. That’s why fixed choke guns can usually be made to outperform screw choke guns, especially in the tighter constrictions. You are the best judge of whether the convenience of changing chokes is more important than that last few percentage points of choke efficiency.

As an interesting comparison, the other day I compared patterns from my wife’s 687 Beretta 28 ga factory screw choked gun and my Perazzi fixed choke 28. The Perazzi 28 has .016″ fixed, but with very long tapers and parallel. The 687 28 has those little short dinky Mobilchokes. With the same shell, the Perazzi patterned slightly tighter and more uniformly with its fixed .016″ than the Mobilchoke Beretta 28 did with .024″. This may not be apples to apples, but it makes a point.

If you want to reduce the muzzle weight of your Beretta, get Briley to backbore it slightly before you have them screw choke it. That’s probably the best way. If you want to add weight, have them fit the gun with extended chokes. If you want the weight and balance to remain the same, just have them insert standard Thin Walls.

Best regards,

Bruce Buck
The Technoid writing for Shotgun Report, LLC
(Often in error. Never in doubt.)
http://www.ShotgunReport.com

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