doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com long choke tubes vs short ones

Has anyone had experience with comparing the longer Briely choke tubes with Colonial or the shorter choke tubes as far as patterns are concerned?

Do the short ones stack up?

choke tubes in a double ? what are they ? paul

A useful a modern alternative to fixed chokes.

Tim, to answer your question ..

The general thinking today and the results that I've personally seen on plates would indicate that the actual choke constriction has much more to do with the pattern than the length of the choke itself. It has been a topic of conversation/discussion for at least a hundred years & I expect the jury will remain 'out' on this subject for at least another century, and then come in 'hung'.

As many never get around to patterning their guns, it is oft more a question of how the user perceives the issue anyway.

If you will look around, you can find some published comparisons of Beretta 390 type guns tested with standard 'short' choke tubes and virtually a myriad of after market longer or 'extended' ones. Similar constrictions generally produce similar percentages, all other things being equal.

The trap shooters at our club swear by the "in the barrel" tubes for lead and then insist that the extended ones work best for steel. Imp Mod for 2's BB's and T's.

bill

Such questions can be answered fairly definitively when more shooters start using Dr. Jones's pattern analysis program. Way too much of our pattern "knowledge" is based on an eyeball impression of one shot. Statistical "truths" are another kettle of fish.

I have compared a Hellis game gun that has a 7" choke taper of 0.035" constriction and an Ithaca 2 1/2" taper for 0.035" constriction. They both produce (drum roll) full choke patterns unless I toss a spreader wad into the load. I don't present this is irrufootable evidence of an all time and all place truth - rather as a pointer for the "normal envelope of taper lengths. I'd opine that extra long tapers would tend to more open performance than their constrictions would indicate and that excessively short tapers might well do the same. "How short and how long do tapers (large and small taper angles) have to be to produce patters divergent from expected for given constriction?" is a good question.

This very question was addressed several years ago by "Gun Tests" magazine. Their extensive tests indicate that the Briley longer tubes are superior to any of the shorter tubes and worth the extra cost. I believe they even called them a "best buy". Their work indicated it had to do with the increased number of "flyers" produced by the shorter tubes. Best, Dr. BILL

Tim,

A Choke design that has a parallel section, whether your talking a fixed choke or a choke tube, will pretty much always produce the densest long range pattern, especially with larger shot.

This parallel section needs to be longer, the tighter the choke constriction is. Thus, the parallel section in a Full choke needs to be longer than said parallel section in a Modified choke.

A parallel section in the choke system means a longer choke than most times found in a conical one.

So, the longer choke tubes are more of an advantage for tighter chokes, longer distances, and bigger shot.

For the skeet shooter, using a skeet choke and #9 shot at 15 to 25 yard distances, it probably makes very little difference if the choke tubes have a parallel section of not, and thereby the longer choke tube with a parallel section versus a shorter conical one has no real (or big) advantage in that application.

For the hunter pass shooting ducks at 50 yards with a Full choke and size 4 KTM or Bismuth pellets, the longer choke tubes with a parallel section will be advantageous.

Hope this helps.

TSAB - do you have data on chokes with a parallel section following the constriction? I have read this before, but can't find any theoretical reason for it. So, I wonder if it can be substantiated at a stasistical level.

Claude Purbaugh, the originator of sub-gauge tube inserts, told me the parallel section should be long enough to contain the entire shot charge. He did not distinguish between the degree of choke, nor do I know if he had ever proven this theory in any manner. Most of what I've read suggests that some parallel gives the best(whatever that means) patterns, but also if the parallel section is too long(whatever that means) the choke will produce less, maybe no constriction. This also suggests, to me, that inward deflection or acceleration produced by the approach taper is what makes choke work in the first place. JL