Point Of Impact-How Close Is Good Enough?


Dear Technoid,

I have been shooting my over under for 0ne year and decided to take it to the shooting board to see what the POI is. I set up at about 20 yards with a shooting bench and shot a box of shells at the targets, white roller paint around a steel bolt. After shooting all combinations of chokes from top to bottom barrel, the top barrel was right on and the bottom barrel was one inch low. That seems to me to be as close as one could expect. I tried another O/U of mine and it was 2 inches high and 1 inch to the right and 2 inches low and 1 inch to the left. Based on this I retired the second gun. I could have chokes made to correct the bottom barrel of the first gun, but that just doesn’t seem necessary. How close do the barrels need to be? Thanks you

Peter

Peter,

First a definition of terms: Point of Impact (POI) as I use it is where a particular barrel shoots with a given load at a given distance when aimed like a rifle. Each barrel has its own POI. Just because they are soldered together doesn’t mean that they will both shoot to the same place- as you so properly noted.

How close does the point of impact of the two barrels have to be? That depends. I know of one manufacturer who felt that 8″ of separation at 40 yards was acceptable. Wouldn’t be for me, that’s for sure. Ideally, one barrel will shoot exactly to the same place as the other. Good luck on finding that.

Figure it this way. Your effective pattern at a given distance with the correct choke is roughly (more or less, sort of) 24″. How much of that do you want to give up? Your patterns were made at 20 yards, so double the POI errors for 40 yards. That said, as you so correctly mentioned, no gun is perfect. A little bit of separation is just a fact of life. Also, POI of the barrels will change slightly with the strength of the shells you are shooting.

Now here’s some good advice: If you have a gun that you own and shoot well, don’t test it for POI. It’s like going to the doctor when you are feeling good. All you can do is break even or lose. Many years ago I once had a Belgian Browning Superlight that I was absolutely deadly with on birds. The Devil, in the form of a shooting buddy, talked me into testing it for POI. I told him that I had tested it many times with both barrels on live game it is was perfect. But I tested it anyway. Of course the top barrel shot almost a pattern high at 40 yards. I never felt comfortable with that gun again and still wonder why it shot so well for me with both barrels. Another Superlight that I had had perfect POI convergence. Go figure.

My rule of thumb when getting a new (to me) gun is to immediately test its POI. I had a two barrel Parker Reproduction set with fixed chokes. One barrel set was perfect, but the other shot the left barrel far to the left, way off of the POI of the right barrel. The left barrel had plenty of choke, so I took it to a good gunsmith and he simply ground off some of the fixed choke on one side and brought the left barrel’s POI back in to match that of the right. You need a good gunsmith (my guy is now retired) and you do lose a bit of choke constriction, but it can be done with a fixed choke gun. Screw chokes are different. Briley will make you eccentric screw chokes if you wish, but that starts to get complicated.

Moral: check POI before you buy. If it is a used gun, you get a 3 day return privilege. Use it for testing. If the gun is new, you are on your own and have to deal with the manufacturer. Calling them to find out what their policy on POI convergence is before you buy might be wise. You may be surprised at what they tell you.

Best regards,
Bruce Buck
Shotgun Report’s Technoid

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Field Test: Long Beard XR 20-Gauge Shotshells


Winchester’s popular Long Beard XR is finally available in a 20 gauge—and it exceeds expectations.

Source: Field Test: Long Beard XR 20-Gauge Shotshells

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Benelli Ethos 12 Gauge


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First Look: Benelli Super Black Eagle 3


Here are five things you need to know about Benelli’s new Super Black Eagle 3.

Source: First Look: Benelli Super Black Eagle 3

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High Shooting Trap Gun


Dear Mr. Technoid

I purchased a new bt-100 about 10 months ago. My scores went from 18ish to 22ish a number I am happy about. However I patterned the gun about 3 months ago and with 3 shots on each sheet there are no more than 10 pellet holes below the horizontal line drawn through the bullseye I shot from about 15-16 yds using a full choke.

Should I be compensating for the high gun or is there something that should be done to the gun oooorrrr should I leave well enough alone and just practice.

Thank You for your time.
Kevin

Dear Kevin,

Well, I just dunno. It all depends. Do your patterning at the distance at which you will be shooting the bird. If you are a 16 yard shooter of average speed, that will be around 32 to 34 yards. That will give you a real idea of how your gun is patterning in practical terms.

Let’s say it runs half a pattern high. Is that too high? It depends on what you want. Trap birds are always rising at the distance at which they are shot. A high shooting gun is an advantage. I set my gun up to be flat shooting because I use the same gun at sporting clays and skeet as well as trap. The advantage is that I get to use one gun for all the games. The disadvantage is that I have to cover a rising trap target and thus don’t see it as clearly as someone who has set his gun to shoot high and can hold slightly under the bird. It is all a compromise. With a single barrel gun, there shouldn’t be much of a compromise because you can’t shoot anything except trap with that gun. It might as well be set up optimally for trap and that means shooting a bit high.

So, a little high is good. How high is high enough is up to you and the way you shoot. Naturally, you don’t want it TOO high, but after a while you will be able to judge your breaks and tell where you pattern is hitting the bird. If you can’t see this, then ask a friend to stand behind you and watch the breaks. After a while he will be able to see if you are hitting them on the bottom, top or middle of the target. If your gun has screw chokes, use the tightest choke when doing this testing. It will show how the bird is breaking more clearly than an open one.

Best regards,

Bruce Buck
The Technoid at <www.ShotgunReport.com>
(Often in error, never in doubt.)

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Shot Size


Technoid:

Having grown up with a 20 ga. Win. M 12 I like 20 ga. guns, except where 12 ga. is obviously needed, such as duck hunting with steel shot.

When shooting a 20 ga. O/U marked IC/M that throws about that based on my nonrigorous patterning I am wondering which shot size is indicated as the best bet according to the prognostications of Herr Gauss.

Patterns will be inevitably thin down range, there is no getting around this. Over the years, on game and clays, I have switched around, indecisively, between shot sizes. Sometimes I use #7.5 or #6 (if it is not a registered shoot I feel free to use whatever I might use in the field; after all that is what Sporting Clays was supposed to be all about) for dove and clays (sporting, skeet) thinking that I want a kill with a one-pellet hit.

Other times I may use #8 or even #9 thinking that filling in the pattern may be best. Then I think, “Why is 3 or 5 small pellets bouncing off the target better?” To confuse matters further I enjoyed reasonable success using #4 shot in 3″ .410 bore (M 42 & Fox SxS) on dove and quail; I knew I could not depend on the pattern, only the “Golden BB”.

Now that my Federal brochure lists Gold Medal 20 ga. sporting loads in #8 and #8.5 only and 28 ga. and .410 bore in #8.5 only I am doubly confused. Apparently Federal does not abide the Golden BB Rule and feels that patterns must be fleshed out to help insure multiple hits. If this were some other ammo maker I would not be bothered, but Federal’s Gold Medal brand stuff is legendary not only for quality control but for the science and engineering behind the product specification.

What is the Technoid’s opinion?

Jay

Dear Jay,

Well, I dunno. Gaussian distribution and the bell shaped curve don’t really care about pellet selection. All pellet sizes follow the same laws of distribution. Pellet selection is as much personal preference as anything else. Here’s a story:

I was down in the Cauca Valley of Colombia some time ago shooting dove. This was when they still had LOTS of dove and hadn’t changed crops. At times the dove were really high and I was shooting to #7-1/2s. I was getting a lot of “gliders”, birds that were hit but glided for a good distance. They didn’t fall right down they way they should.

At lunch I asked one of the other shooters whom I had seen shooting really well. He was taking dove at awesome heights. He said that he used #9s exclusively. He had been making this trip three times a year for quite a number of years and had experimented. His conclusion was that #9s worked best because the dove was a very “soft” bird, but also had a small vital zone. It was more important to get one small pellet into exactly the right place than a big pellet in the wrong place. The far greater pellet count of the #9s gave him a better chance of doing this.

Since shooting several cases of ammo per day was no problem with so many birds, I experimented with a case of #9s and found that he was exactly right. In spite of shooting at considerable heights (shots I had been passing up the first day), I killed more birds and I had a far larger percentage of dead in the air birds.

Today when I shoot #9s in American dove fields, people look at me as though I were crazy. They all want #7-1/2s or even #6s because the birds seem so far away. Dove always look farther away than they are. I stick with the #9s and have not been disappointed. The smaller the gauge, the more attractive the #9s are for dove because pellet count increases in importance as shot load decreases.

However, it all depends on the bird. On ruffed grouse (my favorite game bird), I use #7-1/2 in my open first barrel and #6 in my second barrel. I do this in 20 gauge or 12. Over the years I have found that this is the combination that works best for me and provides less work for the dog.

With pheasant, it is #5s and occasionally #4s. I was shooting at a FITASC parcour one day and shared the squad with an excellent shooter whom I had not met before. We got to talking and I commented on how much I admired his shooting, but also on the fact that I hadn’t seen him around. He said that he mostly went around the country shooting for springer trials and didn’t shoot many clays. Springer trials generally use pheasants and those dog handlers want that bird to fly a bit to show the dog off and then dropped DEAD for an easier retrieve. He said that he shot 1500 to 2000 pheasant a year. His Perazzi was choked Improved Modified and Full and the shell he and the other trials guns used was a Federal #5. If Federal #5s can reliably stone a departing pheasant at 35-40 yards, then that is the shell for me. This springer trial stuff is serious work and there is a lot of pressure on the guns to perform well. If there were a better shell than the best Federal #5s, they would use it.

The bottom line is that different birds can take very different shells. On clay targets, I switch around a good bit too, but if I were limited to only one pellet, I would take #7-1/2 in 12 and 20, #8 in 28 and 410. I am not a big fan of #8-1/2s for longer shots.

When we shoot sub-gauge sporting, we do so on a standard sporting course, not on some little dinky one with skeet shots. We equalize the little guns by giving them a handicap that we have worked out over the years. Everyone knows what a 410 can do on a 20 yard skeet bird, but you might be surprised what they can do at 35 yards with the right pellets. Like you, I shoot an old Winchester M42 in 410. When the moon is in the right phase and my biorythms are in sync, it can do surprising things at distance with #8s.

I reload all my sub-gauge ammo and shoot mostly factory shells in the 12. Reloading the sub-gauge makes sense in two areas.

1) I can get any size pellet I want and

2) you save a ton of money.

It costs less than $5/box to reload 28s and 410s, but they cost close to $12/box new. If you reload sub-gauge, it means that your round of 25 clay targets is pretty much free compared to buying the ammo. Modern reloaders are so good that you really can load quickly. I like the MEC Grabbers in 28 and 410 and can easily load 15 boxes per hour and probably 20 if we bet a beer on it. Besides, if you had your own reloader, you could experiment with all the different shot sizes. You can usually get high antimony #8-1/2s if you order them from your shot dealer. A lot of the skeet guys like them for doubles and I have seen more than one 16 yard trap shooter use them.

Best regards,

Bruce Buck
The Technoid at <www.ShotgunReport.com>
(Often in error, never in doubt.)

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Same Citori


A question on Browning sporting clay shotguns. Browning made a GTI for a number of years then discontinued manufacturing this model. They now make a 725 sporting clay. What is the difference between the 725 and the GTI ? Why did they discontinue making the GTI ? I have an opportunity to purchase a GTI but do not know much about this gun.

Thanks for your help.
Terry

Dear Terry,

All 12 gauge Browning Citoris are basically the same. The only difference from one model to another is the wood configuration, barrel length, ribs and receiver decoration. There are some other running production changes in barrel thickness and monobloc construction too. Older guns like the original red letter GTIs had the short Browning Invector chokes.

I have no idea why Browning discontinued the GTI, but it probably had something to do with the trend in ladies’ hem lines. It is all really just fashion and the desire to have a new product to market. Personally, I always thought that the red letter GTI was one of the best feeling guns that they made, but I also like the 325, 425 and some of the later Ultras. It just depends on what you like. Under the skin, they are all the same strong, durable Citori.

If you like the feel of the GTI and have a chance to buy one in good condition for a fair price, I wouldn’t hesitate.

Best regards,

Bruce Buck
The Technoid at <www.ShotgunReport.com>
(Often in error, never in doubt.)

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