Choke Guage question ....

Ahsan Ahmed

Ahsan Ahmed

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How does one accurately read the following guage?

For example, if you insert the guage into a choke tube or a bbl that maybe marked as "Mod" - should the marking (M) on that Guage stay visible right outside (on top of) the tube/bbl or concealed just inside?

Hope I was able to adequately word my query :) Thanks,

Guage-1.jpg
 
An interesting question. I would suppose that such gauges are made to show the marking (in letters) clearly legible. An outside micrometer should confirm this.
Of course you know that choke is really the difference between the inner bore diameter and the smallest diameter of the choke - a gauge such as illustrated can't give any indication of the amount of this constriction, only an approximation of the size of the choked diameter that is being measured.

Cheers,
Bob
 
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bluedcanoed said:
a gauge such as illustrated can't give any indication of the amount of this constriction, only an approximation of the size of the choked diameter that is being measured.

Cheers,
Bob
Click to expand...

Absolutely concur. Just not sure how the guage is supposed to be viewed to provide that aprox idea.
 
Ahsan Ahmed said:
How does one accurately read the following guage?

For example, if you insert the guage into a choke tube or a bbl that maybe marked as "Mod" - should the marking (M) on that Guage stay visible right outside (on top of) the tube/bbl or concealed just inside?

Hope I was able to adequately word my query :) Thanks,

Guage-1.jpg
Click to expand...

To me, that tool appears to be marked atop the areas that determine the size. In other words, the area marked is the part that would fit into the barrel to determine its constriction.
 
easy said:
To me, that tool appears to be marked atop the areas that determine the size. In other words, the area marked is the part that would fit into the barrel to determine its constriction.
Click to expand...

Yes. Look at 16 F. That would have to fit inside to indicate 16 Ga. full choke because there is no smaller diameter to try to fit inside the barrel.

Darn good question.
 
Depends .... :)

For the Galazan (Brownell's) Choke Checker I have, the "Mod" band will not enter a standard Remington "Mod" choke .... the checker's band width mics. .707", whereas the Remington choke is .711 ( or .018" constriction for a .729" standard Remington bore).

The choke checker shows "1/4 choke" on a Beretta Optima Modified extended tube ... the 1/4 choke band mics. .717". However, the Beretta choke mics. .715" or .018" ( Modified ) constriction - for a .733" nominal Optima bore.

At best, the choke checker is only an approximation.

Band diameters on the Brownell checker are:

.727" - Cyl., .722" - I/Cyl, .717" - 1/4 choke, .707" - Mod., .698" - I/Mod and .688" Full. These are reasonableapproximations to check barrels from .725" - .729" ... but not the overbore barrels more common today like Beretta's Optima ( .733") or Brownings Invector Plus ( .740" )

A full on bore/gauge type barrel micrometer (like a Baker ) is far more accurate and pretty much indicative of choke ... however, the only way to gauge actual choke performance for a particular load is to pattern ... using at least 5 shot / pellet percentage averages on paper in a 30" circle at precisely 40 yards from the muzzle.
 
beretta boy said:
Depends .... :)
Click to expand...

I concur with the explanation provided. That checker provides only a rough estimation at best.

FWIW, I checked a fixed choked 12ga sxs (bbls reamed to IC/M by Precision Arms).....the Gunsmith's micrometer (obviously) was/is accurate. When read with my Choke Guage, the M/IC bands were positioned right outside the bbls.

I also measured choke tubes (all marked as Full) for 20ga and 28ga 686 SPs + a CZ 28ga - in all cases, the 28F band on the tool did not go inside the tube.

Ironically, a 12ga 686 SP tube (marked as Mod) and a 20ga Invector (marked as IM) went up all the way to cover the Cyl band on the tool :) ... so much for mass factory produced choke tubes.

Thanks everyone for the input.....much appreciated.
 
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