doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com The Square Load

When I shoot my M/L shotgun I always use the same measure for the shot & powder. Can't say as I ever shot a "Square Load" from it though. What I shot was an Equal Volume load. A square load in my particular gun would have fallen about half way between 1 1/8oz & 1 3/16oz. What I normally shot was an even ounce.
The equal volume loading can be used with whatever shot charge you desire, the Square Load is confined to a shot charge which has a column length equal to its diameter & Absolutely /nothing to do with the powder charge, which could be black, bulk or dense smokeless.

Ted Schefelbein,
They are robust, but work for me. They were European hare, on drive hunts. If I showed up with a 22 rifle, I would be invited to leave and got come back. I always used 1 1/8 oz loads, as far back as high school, in my Sweet 16, 26" inp/cyl. That was back when I could still follow a dog. I would carry the 16 to school, ride home with my cousin, on his school bus; and he, I, his brother, and a dog named Streak would hunt Bobwhite until my mother got off from work and came to pick me up. My cousin would make fun of my little 16, he used a 12. I shot the 1 1/8 oz load, and he shot 1 oz. Which one was little?
Mike

Just because an idea is old does not mean it is antiquated. The concept of square load is not based on theory but theorem. It refers "only" to the load: length equals width. (Height is the term used to describe the high point of projectile travel.)

The square load concept is entirely true because it is a basic starting point for ballistic efficiency. The shot load is acted upon as one entity and for all practical purposes is considered one projectile. For it to perform best, the center of mass has to equal the center of gravity. It is therefore a point found by the intersection of diagonals of equal length, which must be found in the square. If a shot charge performs better or worse than the square load for any given gauge, it is because there are external variables applied.

By example, I could relate that I once had a cheap 16 gauge patent shotgun which was the best long range gun that I ever used. In it I shot the cheapest Federal 2.5 dr./eq. 1 oz. Game Loads, reputed to have very soft shot. On doves, the gun was deadly to 85 yards. Was the square load, the secret of success? No. There were other factors at work. The barrel on that cheap gun was made under the supervision of Harry Pope, reputed to be the best rifle smith of the early 20th Century. And the shells were loaded with slow powder. When Federal substituted hotter powder a few years later, the gun started dusting birds. All of these are external variables. But in shotgun ballistics a square load is always an optimum starting point.

Old Hercules & later Alliant handloaders manua;s gave the length of 1 oz of shot in the various. They did not stipulate the shot hardness or size. I am going to stick my neck out a bit & assume it was ordinary chilled shot of a size around 7� to 8 as these are sizes loades by a lot of target shooters for which reloading has been quite popular.
The column length for 1oz in the 16 gauge was .837". A 16 is .662" in diameter, give or take a bit of manufacturing tolerance.
Quite obviously the 1 oz load did not give superior results in you 16 because it was Square, because it is in fact (.837/.662 = 1.264 ) 26%+ OUT OF SQUARE.
About the only loads which have ever been factory loaded close to square are 1 1/16 oz in 12ga & 1� oz in 10 ga.
The 3/4 oz load in a 28 gauge which is so highly touted as having Near Magical abilities has a length of around 220% its diameter. 1.212L/.550D
Even the � oz load in a .410 is 266% times its diameter. 1oz = 2.18" � 2 for � oz =1.09. 1.09/.41 = 2.6585
These are of course subject to small variations due to actual alloy &/or shot size.
I cannot truly say if I ever shot an actual Square Load in my life. As long as I picked a reasonable load & shot size for the game at hand & THEN POINTED THE GUN IN THE RIGHT DIRECTION I never had a problem with those Skewed Out of Square loads killing anything.
A square load in the 10 is actually 1.27oz ( would be a bit lighter with larger size shot normally associated with the 10), a 12 = 1.0565oz (close aplenty to 1 1/16oz), the 16 = .790oz (25/32+), the 20 = .634oz (5/8+), the 28 = .455oz (7/16+ & the .410 = .189oz (3/16oz).
There are your Square loads, how many folks you reckon shoot them??

The fact that you or I have not done something does not keep physics from being fact. All that is necessary to make a shot column square is to add or remove shot. THAT load would have the highest ballistic coefficient and perform most uniformly. It does so because at the moment of ignition the load reacts as a solid. Lengthening or shortening the shot column alters stability. The fact that a square load is equaled or out performed by any other load is because of external variables.

Some rather interesting physics there VF.

Center of mass and center of gravity are the same unless a gravity gradient is involved, like in outer space.

A single projectile that is only as long as it is wide has very poor external ballistics.

None of that is relevant to shotguns at all, as an 'optimum' or otherwise.

The 'square load' is the ballistic equivalent of astrology.

Re post 854, a shot charge never acts as a solid.

From the moment of ignition, set back and deformation commence. The shot charge shortens under acceleration do to compression of the shotcup petals and the malleability of lead.

When the charge hits the chamber cone, it lengthens behaving more like a fluid than a solid.

It lengthens again at the choke, if there is one.

'Ballistic coefficient' is meaningless within the bore, and only relevant to individual projectiles once bore exit occurs.

In the twelve, 7/8th. to 1 oz. loads seem pretty popular. Once a bit of bore diameter is lost for the thickness of the wad, those could be the mythical square shot column. I always thought the 'square' was sort of a rule of thumb balancing volume and the concept of fluid flow through the barrel with respect to flyers that blow the pattern, but I doubt it matters much.

Generally speaking the inside of the shell is larger than the nominal bore so the column will actually be a bit shorter prior to entering the bore proper. "IF" the thickness of the shot collar inside resulted in a diameter of the bore of about .715" then 1 oz would be square. I have quite successfully fired 1oz of shot from 12, 16 & 20 gauges, a favorite shot load for me over the years for my hunting. Obviously it is not square in all of them but it just never bothered me.
The fit & feel of the gun seemed to always have a lot more to do with my
hit-a-bility than did the gauge or whether the load was Square or Skewed.

Ted, unless your Sotan jacks are different than the ones we have in Iowa, where they really differ from a cottontail is long BACK legs.

Re the 16, my first classic double was a pre-WWII Sauer in that gauge. Had the chambers punched (before I knew better), and shot a large pile of pheasants with it--the vast majority with the high brass 1 1/8 oz loads. I wasn't into weighing guns back then, but I'm sure my Sauer was under Mr. Greener's recommended rule of 96 weight for that particular load. Would not have wanted to shoot a round of trap or skeet with those.

I killed a 25# gobbler with a 1 1/4 oz 16ga "magnum" out of an old Stevens sxs. Shot a few of those--very few--at pheasants. Decidedly unpleasant, mainly because--once I did start weighing guns--I seldom owned a 16ga double that weighed more than 6 1/2#.

For those who prefer simpler math, I've seen many vintage writers tout the 16 based on the fact that the standard 1 oz load is the same as the weight of a solid lead ball that will fit in the barrel. Doesn't work so well for the other gauges.