I do not think your 40.5 is accurate, but again even when I tried 42.7 gr for case capacity, the predicted velocity was way off. I even went up higher and this did not seem to "fix" things in a reasonable fashion.
I use WC 680 (milsurp 1680) a good bit in 357 Max and 357 AR max. When I was working up WC 680 loads for these guns, it was before I had Quickload.
I went back and was looking at my old data. A good bit of data is for revolvers and is not much use for comparison.
For my Wc 680 load with a 200 gr bullet in 357 AR max, I put it in QL and it looks to be overpredicting velocity by around 100 fps.
When I plug in data for some of my 180 gr loads, the QL overprediction is in the 40 fps to 100 fps range.
Not terrible given that I was using a milsurp powder, but not as close as I would like.
Looking at my old data reminded me that as I went over 102% fill (with any bullet), it seemed that I did not like the looks of the primers. Also I remember not liking the force required for bullet seating above this fill.
If I tweak your case capacity to a reasonable 102% fill and adjust the powder burn rate to get down to 2340 fps the calculated pressure comes down to just 51 ksi. If I adjust powder burn rate to get 2213 fps, pressure comes down to 43 ksi.
Now a Handi barrel has plenty of margin for hot loads. For your vintage gun, go "too hot" and I would expect primer failures and/or the receiver face could yield just a little at the firing pin hole (i.e. peen over).
Sounds like you are Ok, but do be careful and pay attention to all of the details as you play around in "uncharted waters".
I use WC 680 (milsurp 1680) a good bit in 357 Max and 357 AR max. When I was working up WC 680 loads for these guns, it was before I had Quickload.
I went back and was looking at my old data. A good bit of data is for revolvers and is not much use for comparison.
For my Wc 680 load with a 200 gr bullet in 357 AR max, I put it in QL and it looks to be overpredicting velocity by around 100 fps.
When I plug in data for some of my 180 gr loads, the QL overprediction is in the 40 fps to 100 fps range.
Not terrible given that I was using a milsurp powder, but not as close as I would like.
Looking at my old data reminded me that as I went over 102% fill (with any bullet), it seemed that I did not like the looks of the primers. Also I remember not liking the force required for bullet seating above this fill.
If I tweak your case capacity to a reasonable 102% fill and adjust the powder burn rate to get down to 2340 fps the calculated pressure comes down to just 51 ksi. If I adjust powder burn rate to get 2213 fps, pressure comes down to 43 ksi.
Now a Handi barrel has plenty of margin for hot loads. For your vintage gun, go "too hot" and I would expect primer failures and/or the receiver face could yield just a little at the firing pin hole (i.e. peen over).
Sounds like you are Ok, but do be careful and pay attention to all of the details as you play around in "uncharted waters".
