Patterning - a real eye opener!

The Baron

The Baron

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I finally snuck out and patterned my 725 Sporting with the extended Invector DS chokes today... and it was quite an eye opener. Loose and pretty splotchy with Kent 1oz #8's at 1200. I feel no need to question the ammo.

I got home and did the 30" circle count. It's a very limited test, granted, but results are shocking:

LM - 45% in 30" circle (from bottom barrel) at 33 yards
M - 50% (bottom barrel) / 56% (top barrel) at 33 yards
IM - 62% (bottom barrel) / 65% (top barrel) at 33 yards
IM - 38% (top barrel) at 45 yards (so, about like skeet... from an IM ��)
F - 63% (top barrel) at 38 yards (about like M)

I've been struggling with long birds in Sporting Clays and since I see now I've been getting about cylinder-skeet performance from the M/LM I've had in the gun, I may have found the reason. At least, that's my excuse and I'm sticking to it. ;)

Here's what the spec'd results should be at 40 yards::
Cylinder 40%
Skeet 50%
IC 55%
Modified 60%
IM 65%
Full 70%
 
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I have owned a few new Browning sporting guns over the last few years including a 725 with the DS chokes and have settled on my 30” crossover target with A set of exrended Midas chokes as the gun for me. But to the point, I have found they all shoot better ( My scores are 15 to 20%higher ) with 7 1/2 handicap loads.
Maybe it’s all in my head, but the numbers don’t lie.
 
Handicap, or higher velocity rounds constrict the choke. Or act like a constriction.

I did the same, but without counting % and was shocked with my Carlson and Beretta chokes out of my 690. I wrote it off as being softer lead in my reloads. I’ve been meaning to test my factory rounds (challenger, Kent’s, AA, Federal target, etc)

I have since run tighter chokes on the 690 since the original test.
 
bunny said:
...I have found they all shoot better ( My scores are 15 to 20%higher ) with 7 1/2 handicap loads.
Maybe it’s all in my head, but the numbers don’t lie.
Click to expand...

Yes, this is my next plan to try some 7.5's and see what happens.

But I'm basically deciding between Brileys and Mullers right now. I'm convinced these loose chokes have cost me birds, and can't have that in my head at the next comp.
 
Kent claims to use 4% antimony in all of their lead shot shells which happens to be about half way between soft (2%) and what is considered hard (6%) so at 1250 fps, you could be getting some deformation happening. As well as deforming the shot, higher velocity also tends to spread the load more than slower velocities.
My favorite load for long shots is the AA Sporting 1 1/8 oz 7 1/2 shot, they're 6% antimony and at 1300 fps, it's a very effective load and quite soft recoiling.
 
Most of the time when I shoot sporting I leave my high end guns at home and use old guns, I have a 1897 pump and a few Ithaca’s, and some others made in the 50’s or 60’s with fixed full chokes, they all shoot incredibly tight patterns, but I don’t find it a disadvantage,as I usually shoot the highest scores of the group. Nothing like beating the Kreigoff, Blazer, high end Berretta crowd with a plain barrel Winchester model 50, or Ithaca 37.
Iam currently using Challenger handicap 7 1/2 loads and find them to be as good or better than anything else out there.
 
Falconflyer - your reply just noted an error in my post. The Kent loads I'm using are 1200 fps, not the 1250 I originally stated.

Interesting note about shot hardness. Maybe I'll try some AA's just to see, but aftermarket chokes are a foregone conclusion to my story.
 
I think your right about the choke tubes but I mentioned the shot hardness thing just because a lot of people don't give it much thought. Generally speaking, (but not written in stone), the more expensive shells such as Remington's STS and Winchester's AA have hard 6% antimony shot. Antimony is expensive and that is what your paying for in the premium shells. Also, heavier shot tends to deform less due to mass and therefore an 6% antimony #7.5 pellet resists deforming a little more than a 6% antimony #8 pellet so just moving up to the heavier shot helps deformation regardless of antimony. Probably the worst combination would be something like the Winchester Super Speed in #8 shot, a 1350 fps load of 2% antimony shot, lots of deformation.
 
Some skeet shooters actually prefer lead shot with a lower antimony % since shot deformation provides a bit of a wider spread at closer ranges. Although this isn't always appropriate for shooting trap at longer distances, that extra one or two golden pellet provides a little chip off of the clay target that still counts on the score sheet. Lead pricing has recently dropped to about .99 cents per pound while antimony is about $3.79 per pound. My "back of the envelope" figures would position a manufacturers cost of materials as follows:
One pound of shot 98% lead with 2% antimony at $1.05
One pound of shot 96% lead with 4% antimony at $1.10
One pound of shot 94% lead with 6% antimony at $1.16
Based on current world market pricing in US $$ for raw materials. Add in the cost of manufacturing and you can see why the price of shot increases every so often.
I'm not trying to hijack this thread or change the topic, but it just got me thinking.
 
Randy Wakeman commented on this a few years ago, here's the measurements he took on the factory DS chokes.

"Browning, in my opinion, has done a fabulous job with the 725 Citori, the best O/U they have ever offered and the best in its class on the market today. But. The “but” is the ridiculous choke tube performance. The lower barrel of the 725 Sporting measures .739 in., the upper barrel .738 inches. The inside diameters of the choke tubes are SK = .742 in. IC = .739 in., MOD = .732, IM = .726, and Full at .701 inches. Only the Full is designated as a lead-only choke tube. The Skeet tube is no constriction, actually a reverse constriction choke, while the IC tube is either no constriction, or a .001 in. constriction contingent on what barrel you screw it in to. By common standards, the Mod and the Improved Modified are actually nominally IC and Mod tubes, while the Full at .037 - .038 actual constriction really is a Full. For comparison, the flush DS tubes of the 725 Field came in at IC = .739 in., the Mod at .731, and the Full at .702 inch, essentially the same nominal dimensions at the extended tubes either the same (IC) or within one thousandth of an inch (Mod and Full)."
 
Yikes - You'd think Browning would at least let their customers know about their unusual choke dimensions! In essence, they've applied steel only specs to all their chokes except full.
 
That's why I'd sooner use the English method of choke tube designation or 'points of constriction' rather than IC, MOD, etc. In the case above, the mod tube with .732 diameter fitted in the bottom barrel that measures .739 is 7 thou difference or '7 points of constriction. This starts to mean something when you realize that a MOD tube should normally be around 20 points of constriction and 7 points is barely IC. You have to measure your tubes and barrels to get POC but it more readily describes just exactly what you putting in your gun.
The factory tube markings are purely a guideline for those that don't measure or pattern their tubes and in my experience, I think that the majority of shooters don't measure or pattern their tubes because they don't realize how loosey goosey the manufacturers are with the tolerances. Of course, this all means little if you don't spend an afternoon counting tiny holes in a piece of paper at the pattern board with your ammo of choice.
 
When I had my 725 Sporting guns, I patterned them, and then bought Briley extended choke tubes to replace them. The patterns were more consistent , as well as matching the labels.
 
Falconflyer said:
I think your right about the choke tubes but I mentioned the shot hardness thing just because a lot of people don't give it much thought. Generally speaking, (but not written in stone), the more expensive shells such as Remington's STS and Winchester's AA have hard 6% antimony shot. Antimony is expensive and that is what your paying for in the premium shells. Also, heavier shot tends to deform less due to mass and therefore an 6% antimony #7.5 pellet resists deforming a little more than a 6% antimony #8 pellet so just moving up to the heavier shot helps deformation regardless of antimony. Probably the worst combination would be something like the Winchester Super Speed in #8 shot, a 1350 fps load of 2% antimony shot, lots of deformation.
Click to expand...

The lower antimony shot deformation is very interesting and would explain the number of extremely deformed pellets that I have been hit with and recovered and the number I have discovered laying on the trap house roof next to the #8 station.
 
Barrels and chokes play a large part in pellet deformation as well, long forcing cones, over bore barrels and long choke tubes are all relatively recent developments. For an example, an older Beretta 12 gauge with 3/4 inch forcing cones, a bore diameter of .725 and mobil choke tubes with about 2 inches or so of taper will deform pellets more severely than a Beretta 692 with 14 inch forcing cones, a bore of .733 and 3 inches of taper in the choke tubes. These refinements have all served to improve patterns by reducing deformed pellets called flyers that don't fly true and stay with the non deformed pellets. It's like pouring gas through a funnel, the more gradual the taper, the faster and easier the gas will flow.
 
I have advocated for many years that if your a serious shot gunner you pattern your gun to see what's going on. And it always turns up many surprises. The resulting pattern from a barrel choke combination has many variables. One has play with the variables to see what will give you the best results for your needs. You have turned up one fact in your findings that most fellas have a hard time believing and that is that no two barrels will give exactly the same pattern with all other variables being equal.
 
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