Well, I´m going crazy!
I got a new mold, my first premium mold besides previous lee´s.
This is a MP for a 124 gr SWC in 9mm..
A beautiful mold of a quality that impresses me and a beauty to cast with..
Now, the thing that makes me go crazy! I can´t get those nice boolits to shoot straight!
Cant hit a 1x1meter paper at 25 meters rested.. the few that does are all over the paper and some goes sideways!
I´ve also tested some of the loads in my other 9mm´s with the same result!?
Facts: Alloy used is my spiced 20:1.
Actual xray test says 93.7%Pb, 4.96%Sn, 1.28%Sb and 0.07%Cu.
According to the calculator that would end up at about 11 Bhn aircooled.
I´ve used this alloy for other 9mm boolits and for stiffer 38spl and softer .357 mag loads before..
Gun: 9mm 1911 that normaly prints everything I feed it into 3-1 inch groups rested at said distance.
I´ve shot cast boolits in the gun before, both Lee´s 105gr SWC (but I have trouble with feeding due to short COL) and Lee´s 125gr RF. The 105gr shoots very nice, but feeds lousy, the 125gr feeds better but doesn´t shoot as great.
Barrel is slugged to 9.06mm = .3566
Tests are done with clean barrel and the loads doesn´t seem to lead.
Previously used boolits of other designs has been sized to .358 with good result.
Boolits: Boolits have rested for two weeks before use..
Boolits comes out at 131gr with this alloy, lubed with Randys Tac 1..
Boolits have been sized to both .358 and .357 ..same lousy result.
All boolits used in the test are weighted and in + - 0.5 grain from 131gr
Tapercrimp are soft but passes a presstest. (boolit dia + 2x case mouth thickness +.001 crimp.)
Pulled boolit shows no swaging.
Loads: I have used soft loads of Vithavouri powders N-310, N-320 and N-340
Sorted Norma cases and CCI Sp primers.
Velocity of tested charges has been very even, spreading just a few m/s from high to low.
COL is set to 26.5mm (1.043inch) due to the chamber / edge of the boolit for proper fit.
The few that hits paper are either randomly all over, or hits sideways.
2 strings of 5 shots was tested for each load with N-320 and N-340: sized..357 and .358
N310
sized .358
2.2gr, av. vel 250m/s (820f/s)
2.4gr, av. vel 260m/s (853f/s)
2.5gr, av. vel 269m/s (882f/s)
2.7gr, av. vel 278m/s (912f/s)
2.9gr, vel? chrono error.
3.1gr, vel? chrono error. Flat primers!
N320
3.2gr av. vel 294m/s (964f/s) .358
3.2gr av. vel 296m/s (971f/s) .357
3.5gr av. vel 313m/s (1026f/s) .358
3.5gr av. vel 306m/s (1003f/s) .357
3.7gr av. vel 316m/s (1036f/s) .358
3.7gr av. vel 315m/s (1033f/s) .357
N340
4.2gr av. vel 327m/s (1072f/s) .357
4.2gr av. vel 331m/s (1085f/s) .358
4.4gr av. vel 342m/s (1122f/s) .387
4.4gr av. vel 345m/s (1131f/s) .358
The ”best” result I got was 3 shots on paper, with two going sideways!
I also shot a known load at this session, and those printed a nice 2 inch group point of aim.
I was trying to figure out what was happening, and fired 3 shots from various distances, 5, 10,15,20 and 25meters, 15 shots in total with one of the loads that I had some extra of.
5 meters printed point of aim, clean holes. 10 meters, on target but opened up quite some. 15 meters was barely on paper, all over the place and two was showing tendency to keyhole. At 20 meter I only got one on paper and that went sideways. At 25, none on paper and I could see the impact in the sandberm behind.. way off in all directions!
The thing I can´t get my head around is why?
Why is this problem so extreme, and why does it occur with all different powders, sizes,velocities and in different guns when tried?
The 1911 shoots with cast of the same alloy and size and velocity span!
I have encountered keyholing before, but then usually in revos with solid WC with too soft loads that doesn´t stabilize (470f/s) or with HBWC pushed with a slow powder with to much muzzle push to blow the skirt or tip it over.. but this is new to me!?
Am I missing something?
(and there´s no use in pointing me to other powders, as Vitha is the only one available here.)
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MiHec
