I’m not sure. I mainly loved the formula because I can measure shot cups and calculate the diameter that should fit before buying a mold. If the pellets cause pickle bumps bad enough, there will be feeding/reliably issues.
If the pellets are in a shot cup, it’s purpose is to protect the payload, right?
It’s been a long time since I took geometry but I think the flats would be fairly evenly spaced. Two flats where each pellet contacts the other and one flat where the choke would mash. So close to a triangle pattern of flat spots.
Is this slight deformation going to be more or less than the layers stacked on top of each other and accelerating to the speed of sound in a split second?
I suppose marking dye of different colors could be used for side contact points vs top and bottom contact points. Then capture fired shot and compare.
All that is assuming the payload hasn’t shifted in the previous 14-24 inches when it reaches the choke.
Maybe this is why more open chokes have been known to pattern better with buckshot?
Consider:
"Indeed, a choke friendly, easy to assemble load!
Two pellet layers, combined with PSB buffer, provide a very fluid transit through forcing cone and choke constrictions."
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Regarding the load discussed earlier:
To this pellet stack (2 x .310" = .620"), add twice the thickness of the wad petals for the suggested choke constriction that will consolidate rather than "mash" the buckshot pellets.
The same is true if you have calculated the diameter of your three per layer pellet stack and then add twice the thickness of the wad petals.
As with all things smoothbore, confirm with your pattern board.
Last edited by RMc; 05-10-2024 at 01:25 PM.
Million dollar question
For lead buckshot at normal useful buckshot range, is 0.005” to 0.010” of “mash” on the pellets detrimental to patterns?
Personally, I haven’t done enough testing to know. Seems like a pellet would deform almost that much dropping it on the floor.
Is it worthwhile to give up the larger mass and kinetic energy to avoid a potential 0.010” flat spot?
How would you capture buckshot traveling supersonic to look for deformation of the pellets, without damaging them in the trap?
Fitting pellet diameter to the choke or the choke to the pellet diameter, with two pellets per layer, is a simple matter as noted earlier. Just remember to add the wad petal thickness x two, if a shot cup or wrap is used.
For traditional three pellet layers, finding the relationship between between pellet diameter and choke constriction requires a little more more effort.
The following can help simplify the process:
d= The diameter of the buckshot in inches.
D= The diameter of the choke in inches.
d = D times.464016288 or D = d divided by.464016288
Again, remember to add the wad petal thickness x two, if a shot cup or wrap is used.
Last edited by RMc; 05-12-2024 at 12:40 PM.
You may find this site to be helpfull:
https://www.engineeringtoolbox.com/s...le-d_1849.html
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |