What diameter buckshot mold should I buy next?

[RMc]

Found it! Load No. 26 where the TUWGL12 is listed on the update page.
All of the components are currently available. Fantastic!

Be sure to post your 40 yard pattern tests here.

[RMc]

The trick is .4641 times the diameter of the bore (or ID of the shotcup) to get the ideal size for stacking in threes.

Wouldn't it be more important to fit a three buckshot pellet stack to the choke?

[Barry54]

Wouldn't it be more important to fit a three buckshot pellet stack to the choke?

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?

[Barry54]

The trick is .4641 times the diameter of the bore (or ID of the shotcup) to get the ideal size for stacking in threes.

Do you have another nifty formula like that for stacking by fours?

[RMc]

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."
------------------------------------------

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.

[Minerat]

I would buy MP molds 8 cavity .310. It a lethal size and fits many shot cups great.

I have this one too. Allows 5 single stack in a 3" . 410. Plus works great in my Simpleshot slingshot too.

[Barry54]

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?

[MusicMan]

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?

High speed camera!

[RMc]

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?

For high performance handloaders, casting your own heat treated, high antimony lead alloy buckshot is the answer to pellet deformation concerns.

[Barry54]

For high performance handloaders, casting your own heat treated, high antimony lead alloy buckshot is the answer to pellet deformation concerns.

So do you select pellet size to fit the choke or do you assemble a load and then tinker with chokes?

[RMc]

So do you select pellet size to fit the choke or do you assemble a load and then tinker with chokes?

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.

[RMc]

Do you have another nifty formula like that for stacking by fours?

You may find this site to be helpfull:

https://www.engineeringtoolbox.com/s...le-d_1849.html

[Barry54]

You may find this site to be helpfull:

https://www.engineeringtoolbox.com/s...le-d_1849.html

Saved to favorites. Thanks!!

[Barry54]

Picked up a Lee #0 buckshot mold. Tried it out today and was struggling with the lower cavities filling out. I had mystery metal in the pot. A dozen or so wheel weights found in parking lots and some window came. Half the pot was something with a little Linotype and jacketed bullet cores. A real Heinz 57 mix. Out of frustration I ended up putting a pound of solder in so it’s at least 19:1 with tin. Got the temperature up around 825 and things started coming together. Managed to cast about 1/2 the pot and the flow started slowing down. Fiddled with it but unplugged it and will deal with that issue later. I’ve got new 0 buckshot to go load!!

Started with some brush wads and 1-3/8 ounce data. I should probably have used a Teflon wrap but was in a hurry and being frugal too. The pellets fit loosely in stacks of threes. 12 pellet load fit on an unfolded 12 pack box at 30 yards with a reasonable distribution in the pattern. The next two loads I tried the BPI BP1253 wads. These only held ten pellets in stacks of twos. The recipe didn’t call for buffer and the crimps were balloon knot ugly. Lastly I tried the MG42 wads (with data from Tom Roster’s manual) and precision Reloading’s spherical buffer.

The BP1253 load grouped 10 in a basketball size at 30 yards. Woah! All of a sudden buckshot patterns got tight! So now on to the MG42 load with buffer. This pattern would fit on a football at 30 yards! Wow!!! I didn’t even sort the shot. I just didn’t use any with tails. So I went back to the house and loaded up a few more. Decided to try the Full size steel at 40 yards. Sweet! A useful pattern at 40. So so I backed up ten long paces behind the bench and sent the last round. It seems far deliberately shooting a shotgun at fifty yards. It rang the steel with authority too.

I did the math and have about sixteen cents of tin in each load, but wow! They shoot so tight it’s worth it 100%!
40 yard pattern.

50 yard pattern on top of the 40 yard pattern.

[Barry54]

Buckshot Bliss!

And I feel like luck and persistence were equal factors in finding it.