You came close with "have a shot". This is a seven inch perf gun. It's filled with shape charges, and blasted through the well casing and cement, out into the reservoir. This is one of the older ones, with the mushrooming of the gun from the charges. Newer ones are machined or scalloped, to eliminate the excess, to aid in removal. Damn good guess though.

These are massively large holes that are exactly what is needed in unconsolidated Gulf Coast sandstones. I am jealous of the size of these holes. They prevent drag, and shear affects on formation sand and are an absolute joy to gravel pack thru. I'd guess, however, as you point out, these are old shape jet charges. Todays TAG technology can burn a hole thru the carrier, thru 23 pound per foot pipe, thru 1 inch of cement sheath and out into the formation 30 inches...with no burs on the carrier whatsoever.

In todays HZ shale oil wells they will shoot much smaller holes with 3 1/8th OD carriers inside 5 1/2 casing. They shoot those holes 4 SPF on 120 degree phasing and 75 foot stages, and 50 stages, there will be 15,000 holes blown in the casing on a 12,000 foot lateral, for example. They'll then pump 6 pound per gallon sand concentrations thru holes that are 0.45 inches in diameter at 80 BPM....50 times, a frac plug set between each stage. It can take 4 -5 days going wide open 24 hours a day just to frac the damn thing. Because the laterals are horizontal, and there is no gravity assist, all the perforating guns have to be tractored in and out. It is very cool.

Thanks for this work of art !