There have been several threads recently where some folks (including some very well known folks) have said very negative things about Browning Invector DS chokes. However, these statements were not supported with any actual data. I asked in those threads for the basis for these negative comments and none was given. I shoot a Citori 725 Trap Max and so far I have only shot actual Browning brand Invector DS chokes; mostly LF and mostly from 16 yards. I wanted to see if there was any truth to the Browning bashing using my gun, my load, and my chokes. If any of you have tried something similar, you know it is a lot of work. I am aware of a video on You Tube that show a single shot each with a Browning choke and a Tru Lok choke and that video makes the Browning version look pretty bad.
I am going to split up posting my results into several posts. There are a number of provisos because this is the first time I have done a numerical analysis like this and there are a number of variables in how exactly you take the data. For example, I had two types of paper and there was an issue with camera resolution so I had to photo each target several times at different resolutions. Next time, I can be more efficient.
My process follows the work of Dr. AC Jones. There are a lot of results published in his book Sporting Shotgun Performance. One thing he didn't do was compare different brands of chokes. Also, his work was done some time ago so things may have changed. I wanted to see what was happening with my actual gun, my actual chokes, using my actual hand loads. The process consists of these steps:
1. Shoot multiple targets for each condition. Three is a bare minimum, five is a decent number for rough results, ten is what you really should do
2. Take a digital photo of each target
3. Analyze each photo with AC Jones' software "Shotgun Insight"
4. Create an Average Analysis using the individual analysis for each target.
Yesterday, I shot 18 targets. My goal was to get five each for Browning LF (Light Full), Browning F (Full), Briley LF, and Briley F. I didn't quite achieve that. I ended up with four targets for each LF choke, three targets for each F choke, all shot at 30 yards. The standard distance for looking at choke patterns is 40 yards and I started at that distance but after four targets (two with Browning LF and 2 with Briley LF) I decided to switch to 30 yards for the testing. I am not including the 40 yard shots in the analysis at this point. I do plan to go back and see how the 40 yard data compares with the 30 yard data but at 40 yards, a fair number of pellets were missing the paper. As I mentioned, I had two types of paper. AC Jones recommends white paper and that is much harder to acquire than brown Kraft paper. I went out yesterday with two rolls of paper, both bought on Amazon. One roll was pure white, 48" across, but only 3 mil thick. The other roll was a Trimaco product that is white on one side and brown on the back. It is nice and thick at 8 mil but the whiteness is not a bright white. It was also only 3 feet across. The color is important when you use Shotgun Insight because white gives you more contrast and the software has an easier time finding the holes. I found that at 30 yards, 3 foot width was enough, and the thicker paper was easier to handle and it analyzed well enough. I do plan to try one or two other papers but now I know 3 feet is wide enough and that width is more available.
The load for all the shots was a load I've been using for quite some time. It uses Fiocchi clear hulls, Fiocchi 616 primers, Fiocchi 1oz wads, 1oz of Lawrence Magnum shot, and Clays powder dropped with a #33 bushing. That gives me an average of 18.6 grains which should be going out at around 1250fps. I have not measured this actual load but have shots hundreds of them.
I am going to end this first post with a simple summary. Data will follow in other posts.
Summary: I did not find anything to support statements that Browning Invector DS chokes suck. In fact, I found that for both LF and F chokes, Browning was more consistent than Briley. I will have to explain what I mean by "consistent" when I show the data. Both produced (on average) Gaussian shot distributions both vertically and horizontally (no holes or gaps with either). However, the Briley F was a slightly larger pattern than their own LF which is opposite of what you expect. Browning F was slightly smaller pattern than LF as expected.
I am going to split up posting my results into several posts. There are a number of provisos because this is the first time I have done a numerical analysis like this and there are a number of variables in how exactly you take the data. For example, I had two types of paper and there was an issue with camera resolution so I had to photo each target several times at different resolutions. Next time, I can be more efficient.
My process follows the work of Dr. AC Jones. There are a lot of results published in his book Sporting Shotgun Performance. One thing he didn't do was compare different brands of chokes. Also, his work was done some time ago so things may have changed. I wanted to see what was happening with my actual gun, my actual chokes, using my actual hand loads. The process consists of these steps:
1. Shoot multiple targets for each condition. Three is a bare minimum, five is a decent number for rough results, ten is what you really should do
2. Take a digital photo of each target
3. Analyze each photo with AC Jones' software "Shotgun Insight"
4. Create an Average Analysis using the individual analysis for each target.
Yesterday, I shot 18 targets. My goal was to get five each for Browning LF (Light Full), Browning F (Full), Briley LF, and Briley F. I didn't quite achieve that. I ended up with four targets for each LF choke, three targets for each F choke, all shot at 30 yards. The standard distance for looking at choke patterns is 40 yards and I started at that distance but after four targets (two with Browning LF and 2 with Briley LF) I decided to switch to 30 yards for the testing. I am not including the 40 yard shots in the analysis at this point. I do plan to go back and see how the 40 yard data compares with the 30 yard data but at 40 yards, a fair number of pellets were missing the paper. As I mentioned, I had two types of paper. AC Jones recommends white paper and that is much harder to acquire than brown Kraft paper. I went out yesterday with two rolls of paper, both bought on Amazon. One roll was pure white, 48" across, but only 3 mil thick. The other roll was a Trimaco product that is white on one side and brown on the back. It is nice and thick at 8 mil but the whiteness is not a bright white. It was also only 3 feet across. The color is important when you use Shotgun Insight because white gives you more contrast and the software has an easier time finding the holes. I found that at 30 yards, 3 foot width was enough, and the thicker paper was easier to handle and it analyzed well enough. I do plan to try one or two other papers but now I know 3 feet is wide enough and that width is more available.
The load for all the shots was a load I've been using for quite some time. It uses Fiocchi clear hulls, Fiocchi 616 primers, Fiocchi 1oz wads, 1oz of Lawrence Magnum shot, and Clays powder dropped with a #33 bushing. That gives me an average of 18.6 grains which should be going out at around 1250fps. I have not measured this actual load but have shots hundreds of them.
I am going to end this first post with a simple summary. Data will follow in other posts.
Summary: I did not find anything to support statements that Browning Invector DS chokes suck. In fact, I found that for both LF and F chokes, Browning was more consistent than Briley. I will have to explain what I mean by "consistent" when I show the data. Both produced (on average) Gaussian shot distributions both vertically and horizontally (no holes or gaps with either). However, the Briley F was a slightly larger pattern than their own LF which is opposite of what you expect. Browning F was slightly smaller pattern than LF as expected.
