I tried to buy some CCI .40 shot-shells, but they are sold out EVERYWHERE! No hope in sight till end of summer best I can tell. We live in Northern NM, Rattlesnake country, where I carry a g23 every day and I want a way to dispatch rattlers if I need to without concern of how im oriented on my property, considering house, shop, cars, neighbors etc.
I read a lot of articles of guys making .45 acp shotshells with .45 win mag brass, creating a bottle neck design that would cycle in their pistols, but nobody was doing it for .40.
I did some research to find the appropriate "doner" brass that I could cannibalize, and finally found the 10mm Mag. I never knew it existed. I ordered the brass and went to town.
First I cut the case down to 1.050 with a jig I made for my drill press that utilizes a forstner bit to do the cutting. 1.050 is the longest I could make the case for it to eject properly.
Next, lube the case really well with a thick past lube and full length resize with the 10mm auto die.
I followed this with a Dillon .223 taper crimp die to create a shoulder for the case to headspace on (a bullet seat die may work as well if it has a significant funel to allow the case to center and enter the die which is smaller than the case), this is a trial and error routine of adjusting the die and checking that the case is headspacing in the barrel. This you do in conjunction with the third die, a 9mm Luger sizing die, to sharpen the shoulder a little more. Actually a fourth stage is done during test fire which will "fire form" the shoulder nicely for proper headspacing on future loadings, and improves the ability of the round to cycle the slide.
I cut open some 12 ga shells to rob the powder and shot. The wads were made by sharpening a 10mm case and 9mm case. I cut the inner wad from thin cardboard with the 10mm case to separate the powder from the shot. I used a sheet of thin (.040-050")HDPE cutting board material for the top wad cut with the 9mm case. Sharpen the cases with a deburring tool and use a hammer to smak it through against a piece of plywood.
Once I have the shot in the case with the wad on top, I do a slight roll crimp using a 7.62 x 39 sizing die that I sacrificed for the project. I say sacrificed as I had to grind at least .250" off the end so the case could reach the taperd shoulder of the die slightly rolling it in. This gives my 2 benifits, first it retains the wad, but second it aids the round in feeding.
After working up a load starting with 5gr of powder and ending with 6.8 gr, I got 4 of 6 rounds to cycle in the G23, the last two I had to cycle by hand. In retrospect, these last two might not have been fire formed yet.
In the foreground from left to right, an unmodified 10mm Magnum case, a finished shotshell, and a .40 sw round for comparison.
I read a lot of articles of guys making .45 acp shotshells with .45 win mag brass, creating a bottle neck design that would cycle in their pistols, but nobody was doing it for .40.
I did some research to find the appropriate "doner" brass that I could cannibalize, and finally found the 10mm Mag. I never knew it existed. I ordered the brass and went to town.
First I cut the case down to 1.050 with a jig I made for my drill press that utilizes a forstner bit to do the cutting. 1.050 is the longest I could make the case for it to eject properly.
Next, lube the case really well with a thick past lube and full length resize with the 10mm auto die.
I followed this with a Dillon .223 taper crimp die to create a shoulder for the case to headspace on (a bullet seat die may work as well if it has a significant funel to allow the case to center and enter the die which is smaller than the case), this is a trial and error routine of adjusting the die and checking that the case is headspacing in the barrel. This you do in conjunction with the third die, a 9mm Luger sizing die, to sharpen the shoulder a little more. Actually a fourth stage is done during test fire which will "fire form" the shoulder nicely for proper headspacing on future loadings, and improves the ability of the round to cycle the slide.
I cut open some 12 ga shells to rob the powder and shot. The wads were made by sharpening a 10mm case and 9mm case. I cut the inner wad from thin cardboard with the 10mm case to separate the powder from the shot. I used a sheet of thin (.040-050")HDPE cutting board material for the top wad cut with the 9mm case. Sharpen the cases with a deburring tool and use a hammer to smak it through against a piece of plywood.
Once I have the shot in the case with the wad on top, I do a slight roll crimp using a 7.62 x 39 sizing die that I sacrificed for the project. I say sacrificed as I had to grind at least .250" off the end so the case could reach the taperd shoulder of the die slightly rolling it in. This gives my 2 benifits, first it retains the wad, but second it aids the round in feeding.
After working up a load starting with 5gr of powder and ending with 6.8 gr, I got 4 of 6 rounds to cycle in the G23, the last two I had to cycle by hand. In retrospect, these last two might not have been fire formed yet.
In the foreground from left to right, an unmodified 10mm Magnum case, a finished shotshell, and a .40 sw round for comparison.
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