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Discussion Starter #1 (Edited)
After returning from Africa and meeting Dukefan who lives not far from my home, and learning that besides being a really good guy, he has in his possession two nearly identical Krieghoff K-80 Trap Special 34 inch Top Single shotguns, one of which has a factory original barrel and the other of which has a “tuned barrel” which was done by Tom Wilkinson, I offered to help him determine how these two guns perform. This offer was, no doubt, somewhat self-serving on my part. I wanted to know, as I am sure many of you do, if a Tom Wilkinson Barrel really performs so much better than the factory original barrel that it is worth sending it to him and spending that much money?

So I found this to be a perfect opportunity to do a head-to-head comparison between an unmolested factory K-80 barrel and a modified Wilkinson K-80 barrel.

Of course, to have done this properly, one should have tested the actual barrel before, then after the modification with the same ammo and nearly the same environmental conditions. Of course, that option was not available to us. But for our purposes, since we are doing all the testing on the same day, with nearly identical guns (other than the barrel mods) with the same ammunition, head to head, we should get a fair representation of whether there is magic in the air or not.

If there is something to what Wilkinson does, the results should speak for themselves.

To add to the mix, I brought along my circa 1988 Zoli fixed full choke 34 inch unsingle barrel, and an unmodified old Remington 1100 fixed full choke 30 inch barrel to test. Just to see if the “old technology” was outdated or not.

So, off to the range with a lot of assistance by Dukefan, a lot of trips back and forth to the patterning boards, a lot of shots, and a lot of sweating in the Kansas humidity.

The testing was done in such a manner that we minimized any effect of rising temperatures throughout the day possibly affecting the results, by taking one shot with each gun before moving on to the next shot.

The barrels tested were as follows:

Krieghoff K-80 Unmodified Choke Tube Barrel
34" barrel
3" chamber
0.732" barrel diameter as measured
0.692" choke diameter as measured (super full choke tube)
0.040" choke constriction

Krieghoff K-80 Wilkinson Tuned Choke Tube Barrel
34" barrel
3" chamber
0.740" barrel diameter as measured
0.701" choke diameter as measured (full choke tube)
0.039" choke constriction

Zoli Z-90 Ritmo Fixed Full Choke
34" barrel
2-3/4" chamber
0.727" barrel diameter as measured
0.685" choke diameter as measured
0.042" choke constriction

Remington 1100 Fixed Full Choke
30" barrel
3" chamber
0.735" barrel diameter as measured
0.695" choke diameter as measured
0.040" choke constriction

The ammunition used was Federal Gold Medal, 1-1/8 ounce of 7-1/2 shot with an advertised muzzle velocity of 1145 fps. This is Dukefan’s ammunition of choice. By testing all of the guns with the same ammunition, we can get results that could be fairly compared.

Something we learned anecdotally from this exercise is that guys who shoot Federal ammunition may have a bit of an unfair advantage. When we counted pellets, Dukefan told me two of the shells had 448 and 441 pellets, and another had 414. Hmmmm. All of those sound high for 1-1/8 ounces of 7-1/2’s. The “book” says there should be more like 400. Why is there a 10% higher pellet count than expected?

So I asked him to recount those pellets, and he did, and he counted one more shell just to check. This time, 448, 441, 414, and 447. Hmmm.

I postulated that maybe Federal pellets are smaller than expected. So, I measured a handful of pellets and came to the conclusion that although the pellets were a tad on the small side, nominally coming out at 0.093” for the most part, that doesn’t explain why there are 10% more pellets in these cartridges than there should be. So I weighed the shot charges. Three to be exact.

One was 1.168 ounces, one was 1.170 ounces, and one was 1.169 ounces.

So there you have it. Federal 1-1/8 ounce 7-1/2’s, at least this batch, were nearly 4% over weight.

We checked one Remington STS shell just to see (we did not use any Remington shells for the test) and came up with 394 pellets which sounds more in line with what you’d expect, and the Remington pellets were all 0.095 or larger. A few measured 0.100 which categorizes them as number 7 shot!

I postulated the one Federal shell which counted 414 pellets was an anomaly, so we went with 446 pellets as our analysis number for pellet counts. I think the results bear this out.

All this goes to show you that in order to get proper results you must count pellets. Otherwise our results would be meaningless.

We took 10 shots with each gun (the first shot with the Remington patterned too low to count pellets so we only looked at 9 patterns for this gun.) Photos were taken of the patterns before we took them off the board. I used Shotgun Insight to analyze the patterns.

Testing was done at as near to 40 yards as we could get. We measured it with a 100 foot tape (yes, we went to 100 feet then measured off 20 more, smart guys.)

What did we find? About what I expected we would find.

There’s no magic.

The K-80 Wilkinson “tuned” barrel performed neither remarkably better, nor worse, than the unmodified K-80 barrel, or for that matter, the Remington or Zoli barrels.

They were all about the same. Indeed, statistically the Wilkinson barrel was the worst of the four. But still not bad. Probably the biggest surprise was the Remington barrel. For a magnum hunting barrel, it came from the factory with a “big bore” and was factory choked “super full.” And it performed just as well as the other barrels.

I don't have the nice graphing program Neil uses so you'll have to accept average numbers. But I used the same methods Neil uses.

  • Krieghoff Wilkinson Tuned Barrel – Pattern Efficiency=73.9%, 75% Shot Diameter=27.4 inches

  • Krieghoff Unmodified Barrel – Pattern Efficiency=75.6%, 75% Shot Diameter=27.5 inches

  • Remington Factory Barrel– Pattern Efficiency=76.1%, 75% Shot Diameter=27.5 inches

  • Zoli Factory Barrel – Pattern Efficiency=76.4%, 75% Shot Diameter= 27.3 inches
The pattern percentages produced by the 4 guns did not significantly differ.

The average 75% diameters were the same for all 4 guns.

There was no significant difference in the “central thickening” as calculated.

Another remarkable thing. The pattern percentages and average pellet counts among the four guns are so similar, nearly identical, you’d almost think we faked it. I assure you we did not.

On the subject of “just looking at patterns.” During the day testing, while looking at the pattern paper, shot by shot, both Dukefan and I remarked, “These all look about the same. There’s no clear difference among these patterns.”

And that is true from two perspectives. One, there really ISN’T much difference pattern percentage-wise, among the patterns. And two, even standing the very worst pattern sheets next to the very best ones and looking at them, you can’t tell which one is better just by looking. At least, we couldn’t.

More fuel to support Neil Winston’s stance that you really can’t tell anything by shooting one or two or three patterns; we randomly chose one pattern from each gun and analyzed it just to see what we could see. It just so happened, the ones we chose showed the Remington beat the others hands down. By a wide margin. But when you look at 10 patterns and take the average, the results turn out very differently. Over ten patterns, the Remington patterned well, but not substantially better than the others. Just “about the same.” So if you were to take that one pattern as representative of the gun’s performance, you would be wrong. That one pattern told you nothing. You NEED to do more patterns and you NEED to analyze them quantitatively to really know anything. Anything less is probably no better than doing nothing at all.

So in the end, does this time and effort get you one more target in 100 than you would have otherwise gotten? No.

But what it DID do was to establish that all of the barrels we tested throw patterns that are about how you would expect a full choke barrel to perform.

Can testing like this tell you if your gun barrel is worth keeping, or should be off-loaded to the next unsuspecting trap shooter? Absolutely yes.

And the big one. Does this prove there is no benefit to sending your gun (that you have tested with quality ammunition like AA’s STS’s or GM’s and found that it patterns about like these results) off to a barrel smith for “tuning?” Well, I say it sure looks that way.

Bear in mind, Neil Winston did send a TM9X barrel that patterned poorly to Tom Wilkinson, and he DID make it perform much better.

Nothing against Tom Wilkinson or any other barrel smith, but this testing lends credence to those who say “there’s no magic.” That is, good barrels pattern well. Having them tuned doesn’t make them pattern any better. Sending your barrel to a barrel smith without ever testing it yourself to see how it performs, is throwing money down the toilet.

So should you do this with your gun? Well, that’s up to you. It’s a LOT of work, time, and effort, and the Shotgun Insight analysis is tedious and time consuming.

Being an engineer, I actually enjoyed doing it, and I am pleased with the results.

I think I’ll keep my Zoli for a while.

Dukefan sending a pattern down range.
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The ammunition we used for the test.
20160717_104340.jpg



The patterning board arrangement (the breeze had to be contended with.)
IMG_8373.JPG



The four contestants.
IMG_8414.JPG



Dukefan's two K-80's
IMG_8415.JPG


My Zoli and my Remington "project gun."
IMG_8416.JPG
 

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Well played.
 
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Tim, I appreciate the time and resources you spent in performing this testing. It was a pleasure to be part of it.
 

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Discussion Starter #4 (Edited)
Tim, I appreciate the time and resources you spent in performing this testing. It was a pleasure to be part of it.
Thanks Dominick, for all your help, and the use of your guns!
 

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Thank you for posting this for us to read.

Regarding the barrel smith's work, I had very similar results.
I had two Perazzi barrels from W, and one from A, arguably the two best in the filed.
I patterned them against my other Perazzi factory barrels extensively (Not as scientifically as you or N.W.) without counting unfired pellets.

Those expensive barrel works showed pretty even patterns against somewhat Hot Core patterns from factory, but 75% pattern counts were the same.
In reality, the most important finding for me was none of those tuned barrels increased my average. They didn't buy one single target for me.
 
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Discussion Starter #7
Nice Analysis, nice write-up! I'm most curious about the Remington 1100 Barrel--Izzat' a Keensight Rib?
Thanks!

Yeah, this was a "project" I started and never finished before I left to go work in Africa. It is a 1-1/4" tall Keensight rib and the stock is an "old style" Jack West stock.
 

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This is some very good and accurate work. Most of these kind of modifications do 2 things make the person who does the work $$ and make the owner of the gun feel better about themselves. We all have this mindset in our society today that if we can spent a little money at something it will give us that little edge to win no matter what sport we are participating in, the people marketing sports products do a heck of a job. This game and most sports are so much mental and in that regard maybe it does work. Good job and well documented!
 
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Discussion Starter #10
Timb, not a related question, but how do you like your Zoli?

Thanks!

Hauxfan!
Haux, this is an older Zoli, and the newer ones are in a league beyond mine. Mine is hefty (almost 11 lbs.), built like a tank, but I have had good results with it!
 

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Thanks! I'm going to the Grand to check out some guns and that is one I want to check out. They say it's a pretty good gun.

Hauxfan!
 

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I found out the same thing when I patterned my Remington 1100 Competition Synthetic with the Pro Bore Barrel -vs- my Ljutic Mono. The Remington surely won't last as long as the Ljutic but it did pattern a little better. Of course I could buy ten (10) Comp. 1100's for the price of a Ljutic.
 

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Wow,
how long did it take you two to go down and photo all 40 patterns?
Thank you both for dong all the leg work inc the painful task of counting all those pellets in a shell.....
Its always interesting to see how an experiment goes and what the results look like.
Shotgun insight sure has taken some of the pain out of doing one of these marathons.
Would really like to see a graph of the results for a ten round series on a graph to get an idea of variability in patterns. Im assuming its about the same across shotguns.
 

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Discussion Starter #17
Wow, how long did it take you two to go down and photo all 40 patterns?
Thank you both for dong all the leg work inc the painful task of counting all those pellets in a shell.....
Its always interesting to see how an experiment goes and what the results look like.
Shotgun insight sure has taken some of the pain out of doing one of these marathons.
Would really like to see a graph of the results for a ten round series on a graph to get an idea of variability in patterns. Im assuming its about the same across shotguns.
Thanks for the kind words Bob.

Dukefan counted all the pellets in the days before we got started.

On the day of the test, Dukefan and I got started about 0800 and finished up about 1115. Our modus operandi was to go to the board, post a piece of 48" x 48" paper, mark on the paper which gun we were going to shoot, go back to the firing line, take a shot, walk back to the patterning board with the camera, take a photo of the pattern paper, take it down, and mount another piece of paper.

After a while you get into a rhythm. I would take the photo and go fold the pattern paper, Dukefan would pull out a new sheet, I'd start taping my side, and so on. Teamwork.

It took about 2-3 hours to process 10 pattern photos on Shotgun-Insight, so that's where it ate all my time.

I'm using Excel. Not sure what Neil uses to make his nice graphs. Let me see if it will post.
 

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Thanks for the kind words Bob.

Dukefan counted all the pellets in the days before we got started.

On the day of the test, Dukefan and I got started about 0800 and finished up about 1115. Our modus operandi was to go to the board, post a piece of 48" x 48" paper, mark on the paper which gun we were going to shoot, go back to the firing line, take a shot, walk back to the patterning board with the camera, take a photo of the pattern paper, take it down, and mount another piece of paper.

After a while you get into a rhythm. I would take the photo and go fold the pattern paper, Dukefan would pull out a new sheet, I'd start taping my side, and so on. Teamwork.

It took about 2-3 hours to process 10 pattern photos on Shotgun-Insight, so that's where it ate all my time.

I'm using Excel. Not sure what Neil uses to make his nice graphs. Let me see if it will post.
Saveas a jpg if you can then repost. Looks good but it requires downloading and opening in a reader .
 
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Discussion Starter #19

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Discussion Starter #20
Thanks to flashmax...here are images of the reports I generated in Excel.

Pattern Testing K80 Unmodified Super Full Barrel July 2016.jpg

Pattern Testing K80 Wilkinson Full Barrel July 2016.jpg

Pattern Testing Remington 1100 Full Barrel July 2016.jpg

Pattern Testing Zoli Ritmo Unsingle Full Choke Barrel July 2016.jpg
 
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