...I say Part I because this will (obviously - see below) have to be continued at a later date.
NOTE: Do not read this thread if loading beyond book data makes you worry. Do something else - please. Also, don't be stupid and try to copy me - you might blow yourself up, so just don't. YOU are responsible for YOUR OWN loads and ensuring your OWN SAFETY.
Finally after 3 weeks of snowing or being busy when it wasn't, I made it out to the range.
I took snowshoes and still got a workout - we have a solid 15" out there.
Here's what it looked like:
DON'T TRY THESE LOADS - Stick to book loads and work up slowly - YOU are responsible for YOUR OWN loads and ensuring your OWN SAFETY.
.40 s&w once fired Winchester brass
CCI #550 primer
200gr. Horn. XTP
Loaded to 1.160" COAL
Small samples - 5 shot relays
G29 with 3.8" .40 s&w conversion barrel, 23# Wolff spring set.
Starting load: 5.8 grains
Average : 948
Std. Dev.: 15
Note: this load showcased very good precision (~2" @ 25y)
(note the median around 981 - problem with small samples)
Std. Dev: 23
Std. Dev: 10
Std. Dev.: 25
*STOPPED WORKUP* - WHY? Federal arms lack of case support too far beyond web.
In this next picture is an example of (1) beginning case bulge - not a fracture yet, but building - and this IS a case from this last relay shot today. Basically, I knew this barrel had some case support issues, but I couldn't get a pin in there to measure it properly - it's worse than I thought. The case is not supported quite some distance beyond the web - and this means extra pressure will eventually cause a blowout. I will have to continue the .40 s&w testing with a barrel that has full case support up to the web to get the sort of velocities I'm gunning for.
Note the case bulge on the 10mm - also due to overpressure and right about at the end of the web (KKM) So far I do not own a barrel that has what I would consider appropriate case support for this gun - but the KKM is the closest.
Here are some comparisons of the primers for those two cases in the previous picture - note the primers. The .40 s&w appears as a typical spent primer - not flat and no signs of overpressure - in fact, I do not believe it *IS* overpressure - it's above book loads for sure, but we haven't gotten there yet...this is simply a case of crap case support, not overpressure - Now the 10mm, that's a different story - that case clearly was over pressure and it was fun shooting it, but I had to stop that workup too - read below for that one.
Looking at the primers for comparison:
So since I temporarily stopped the workup on the .40, I figured I would change barrels to the KKM extended (4.45") and see what these 135 noslers would do. I figured 11.6 would be a good starting load - turns out that was a bit much (to start with).
Once fired Scharch brass 10mm
135 gr. nosler jhp
11.6 gr. 800x:
Std. Dev. 35
Wow - look at those flat primers! Lets keep going!
Std. Dev.: 42
Thinking to myself: "Hey, what was that thing that just hit me in the head?"
Turns out it was a primer - three out of five brass threw primers during ejection. Obviously, overpressure.
So, I stopped THAT workup.