doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Patterning, high pressure vs low pressure

Rocketman,

It may have been on the old board, but I posted several notes back when about flattening shot between the bottom of a tin cookie sheet and a steel plate with a suitable bludgeoning devise. The deformed shot does indeed work, and sometimes quite well, but it seems to some extent to be influnced by other factors as well. We'll call them the 'JLV factors' for purposes of discussion, but specifically choke, powder, wad column & velocity come to mind. My best spreader loads have incorporated deformed 'drop' shot [soft], knock offs of the old Remington 'Post' wad and a .200" hard card wad on top of the post wad followed by a tight pie or star crimp. These are 12ga. spreaders normally loaded with 700X powder & 1oz. of shot between the sizes of #7.5-9. I use the larger size shot on rabbits, SC type clays or warm blooded & use Robert Churchill's technique of shooting the ground just under them in both cases. It is absolutely fool proof when the shot is placed there.

That particular recipe for a spreader has been wonderfully effective, for me. Soda straws and golf T's can also be effective as can 'X' wads or even a plain 'post wad', but my findings in the guns or bbls. I patterned assorted spreader loads in generally would only open a full choke [my def for FULL is the old one of .040 constriction] one degree. This load recipe can open some Fulls up well beyond that.

The Russians, when they first dominated International Skeet, were using ammunition specifically loaded for each station. Some, like that loaded & used for station 8 was cubic Aluminum shot. I would have loved to have been able to pattern some of that ammo & one of my retirement projcts on a very long list would be to get some cut from aluminum plate stock on a hydraulic shear. A bit tedious, but curiosity at times just gets the best of us. I have thought of cut pieces of small dia. Aluminum welding rod as being perhaps the easier source, but it would not 'upset' in flight the same, due to being a dif shape.

Jack & I at one time or another on this board have bantered back & forth about plomb disco, raye borings, &c. Got into a fun bit of dialogue one time by the suggestion that Raye borings were for taking Ortolons w/small shot. Prolly shouldn't have pushed that particular button, but all got an education on spirits, glue and other stuff. Its all historic at this point in time & none are on the menus any longer. In your face woodcock were the real intended quarry. I have & also did a lot of patterning with a Briley's difussion choke tubes. I use them with my deformed shot load, sometimes. However, my findings w/good quality factory ammunition [trap loads] was that they throw pretty consistent IC % patterns. Tighter than I would have guessed. Same can be said of several 'rifled' chokes I tried w/similar ammunition. I'm of the opinion it is due primarily to the use of plastic wads in said ammunition, but have not proven it absolutely to myself. I need to do some more patterning with those chokes and older type card/felt wads to further prove that. I'd surely like to see someone publish some pattern tests done with a Paradox.

FWIW, I am in agreement w/your thots on pattern 'patchiness', but will restrict that to game birds/clays inside 35 yards. I have seen some nicely distributed patterns delivered from CYL bbls at reasonable distances [inside 30 yds] and other times the same bbl. w/ a dif load deliver patterns w/a 'HOT' centre, the latter being more the norm, in my limited observations, than not.

Sorry for the ramble, but that's as few words as came to mind to get it said, correctly. Always open to thots & discussion, even if we are re-inventing the wheel. I don't have much time to play at the moment, so can't go be overly experimental, but its on my list ;-)

Patterns are interesting, and I do my share of patterning. My ONLY certainties after all that shot counting is that hard shot helps even distribution (and that is the no. 1 most important aspect of a pattern for me), high velocities hurt evenness of distribution, and larger shot sizes are easier to create nice even patterns with.

The thought has occurred to me that if there were some magic formula for perfect patterns 100 percent of the time someone would have found it by now, what with the tens of thousands of combinations tested over the decades by ammo companies and reloaders.

My procedure works like this. I try a new load with the gun and choke I intend to use it with on paper. I shoot several patterns. If they are all patchy (have numerous places where the quarry in question could be missed inside the pattern) I scrap the load/choke combination. No shot counting, no statistical data generation, just outlining the "empty places", or "holes" in the pattern. If the load patterns evenly, I try it in the field. As much as possible. I am confident enough in my shooting abilities that I believe I can tell if a problem arises over time with the load that did not reveal itself on paper. That statement may bring jeers form the statistical minded members, but I firmly believe that if you shoot a great deal you can begin to tell a lot about loads from their performance in the field over time.

Over the years I have arrived at several loads that serve me well with this procedure. One defies reason, but is deadly effective on crows. One and one quarter ounce of hard 4's at 1240 fps MV, but here's the kicker, through a XXXFull Comp-N-Choke. That's a .655, or somewhere around 74 thousandths constriction, depending on the gun. By all reason that much choke should deform pellets to a fare-thee-well. But, the crows that die at 80+ yards don't know that, and I don't care, because it kills like proverbial lightning. When a load will take 10-12 straight without a miss at all distances and angles, day after day, there can't be much wrong with it, regardless of what the "experts" say it should or should not do.

My solution : shoot more, worry less.

All the best, Stan

Well, I'm having a chuckle at tw's spreader. Looks like a case of belt and suspenders. tw, you should take the petals off that post wad so the shot will scrub, add Bill Murphy's hyper-flubber tygon-tubing sleeve to the post to give em the lateral urge AND shoot it out of a rifled Frenchie. Should yield 45" spread at 5 yds. with a population density greater than that of Tie Siding, WY with say No. 11s. Would we need a sparrow call?

Lenard, low pressure is a descriptor for peak pressure, right? I don't see how peak pressure would correlate with degree of shot deformation whether you're looking for the beautiful turkey pattern or the beautiful woodcock pattern. I always sort of bought into that GD push vs. RD punch thing in terms of all them little BBs making their buddies smile more or less. For tight-beautiful, I think it's got to be Ease on down, ease on down the barrel. I certainly agree with tw's first post this thread.

jack

Jack, I had been thinking about this for quite some time. I just wondered how the particular load I was using could kill starlings out past 50 yards with regularity. Velocity is right at 1200 fps with about 8000 lbs of pressure. Shooting a mod choke, the gun just seemed to really do the number on those long range crossers. I certainly have never read anything about pressure and how it effects patterns. I think you guys have answered the question well. Thanks

Lenard

Considering the shot charge in flight is something like a fat sausage and not flat, do "holes" or "empty places" on paper really disqualify a choke/load combination?

JC

I still think the most effective test for a shotgun is the old cheese cloth tied between two sticks at the appropriate height and the shooter stands back, quickly mounts the gun and fires. After awhile a black splotch will appear on the cheese cloth noting where the shotgun is throwing the majority of its pattern. Either, high, low, to the left or right then the shooter can compensate or if dissatisfied can 'cook' up another recipe to see how that patterns.
All the best

JC - you are right that the pattern is actually a three dimensional "sausage." If the target were stationary, then the 2 dimensional "holes" would a fairly exact indication. However, a moving target will move within the pattern. That means we would need to analize 3 dimensional "tunnels" within the pattern to be exact. That isn't going to happen in my lifetime - far as I can see. So, we are stuck with "patchiness" as a surigate for "tunnelishness." Ron Forsyth (Australian pest control pigeon shooter) did a lot of work on loads that reduced patchiness (per O & T) and found that there was some correlation to field shooting (of which he did a lot).

t1958 - you describe a test for point of impact vs point of aim. This is a useful test, but yields no data on the performance of the actual pattern. Useful pattern data must look at individual pellet strikes in some fashion. The "calibrated eyeball" is the simplest method and, of course, the least precise. Digital photos that can be compared and viewed by numerous "calibrated eyeballs" is a good step up. Counting holes inside a circle of some diameter at some known distance is the next step up. It is labor intensive and gives only rudimentary information. Measuring "patchiness" for a pattern is also a step up, but also is rudimentary in information. The cutting edge of the art currently is Dr. Jones's computer analysis of digital photos of patterns. This method is work intensive, but holds the prospect of real quality data; I'm still working on technique, but firmly believe it will be worth doing in the future.

I find it highly frustrating that there is not data to definitively answer the simple question that launched this thread. As noted, the data needed to get answers to this one, and several other simple ones, is massive. I plan to work on it in retirement and hope several others will join in an effort with common tools and techniques to create data that can be combined.

After having done lots and lots of patterning and analysis some decades ago, I came to same conclusion as some other posters. Load and gun combinations that give high scores on clays and high percentages of kills in the field are the "best".

On patterning such loads and guns, I keep finding that they give patterns that have a rather even density of pellet holes out to quite near the edges. I also notice that these loads generally produce "half hits" (half the clay is smashed) on clays when I happen to get the shot off slightly to the left or right or in front or behind the target. They give nicely smashed clays when I do my part, as well as dead-in-air birds. Lots more fun than counting hundreds and hundreds of pellet holes and doing elaborate analysis.

Niklas