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Making a Semi-Bullet out of a pellet ... ( calber changing a pellet )

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Motorhead:
Been goofing around today in seeing if i can successfully Swag a .22 caliber pellet INTO a .20 caliber bullet ?
I did accomplish a simple way in doing so and it surprisingly worked pretty well too IMO  ::)

Starting with a stub of 3/4" 7075 grade aluminum drilled a .220" pilot hole @ .400" deep, then another 1/2" at .201" ( drills were corner edge broke so to make a very smooth hole ) Then O.D. cut to make an edge so it would drop into one of the holes on the bench block.  Took a punch and beveled the end to be the same angle as the skirt of the H&N barracuda 21.3 grain .22 cal pellet.  Placing a pellet into die / swag tool it sits on the skirt edge. Placing punch centered on pellet and tapping it threw via a few hammer strike on punch drive it thew the swag die exiting as a longer and smaller 21 grain .20 cal "Semi-Bullet"

* The last photo shows the skirt material is being forced along side the punch lengthening the skirt and will be grinding a slight taper on the punch to find that perfect taper where the skirt is a tad thicker and ends up a tad shorter.

Took the first 10 shooting them at 40 yards with a muzzle velocity of @ 870 fps threw a 20" choked LW barrel.   All landed inside 3/8" which was a shock !! .... loading however difficult being the barrel does not have sufficient free bore / leade and upon loaded you forcefully shove them into the rifling.  Got em loaded, but not ideal.

Have read people talking about this in the past, but never seen anyone actually do it ???


Scott


UPDATE;
Went back and ground a shallow taper on the punch. Now as the new pellet skirt is formed it does so with a tapering thickness and NOT pulling the trailing edge lead further back. Done with the reground punch OAL of the new .20 cal pellet / semi-bullet is @ .015" shorter that the first ones shown.  They fall off the punch now too once exiting swag die.

anti-squirrel:
Now that you've made it and we hear how it shoots, I'm curious when some intrepid manufacturer will make these shaped as yours looks.

Dairyboy:
Very cool!

Motorhead:
Macro is hard to get a good focus ...
but here the skirt after tapering the punch being non distorted and the original trailing edge minus the pulled lead.  second pic the tapered punch.

I also put some JSB 15.9's and some Crosman 14.3 domes threw the Swag die and shot them ... at 40 yards those too hanging inside 3/8" +/- proving the Die works ... who-da-thunk ???

K.O.:
Hmmm  almost  a full 2 tenths...wonder about  3 tenths... a new 25g .22 JSB..?  or another path to 30g + .22 pellets... Hmm...

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