This is not a recommendation. I have read both sides of this debate for a couple years now. Both sides made good points. And I was leaning to the don’t do it side.
I decided I would check it out for my self, I ordered the Lee 175gr mold, and a Size die .001 over my bore diameter.
I cast 100 bullets from the alloy I use in my other pistols, with my Saeco tester; I get a reading of 18 + BHN conversion.
The average weights of these bullets as cast were 174.5gr.
I loaded these on my Hornady LNL with 4.8 gr, of W-231and CCI standard S/P primers, I used range brass as I felt it would show excessive pressure better than new, the bullets were seated with an oal of 1,115.
I shot these over my chrony , I shot four strings of 10 rounds, First 10 the average FPS was 950 FPS, Rounds 25 to 35 average 943FPS, 50 to 60 Average 943, and the last group 90 to 100 was 962 FPS.
I removed the barrel and ran a clean patch down the barrel at 25, 50, and 75, rounds looking for leading, and then cleaned the barrel at 100 rounds. I found no leading.
100 rounds is not the greatest test, but if the Glock 40S&W were as bad as some say, I should have seen some signs of Leading in 100 rounds.
I looked over the Brass and could not see any signs of excessive pressure.
As I said this is not a recommendation, but I now believe if done properly cast bullets can be shot in the early model Glock 40S&W, I will continue to shoot lead in mine, I will try backing off to 4.6 gr, of W-231, this should not be a problem.
