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10mm 200gn Hardcast 800x

Goal is to push the 200gr hardcast out to 1,300fps.  Some pressure signs are ok, since I don't plan on reloading any of this brass other than powder puff range rounds.

I started off with 9.0gns of 800x.  No signs of pressure, and I was certainly hitting the 1,300fps mark, but, my spread was pretty crappy.

I have read that 800x starts to smooth out at higher velocities and pressures, which these results actually show.  On the higher end, the spreads dropped in half.

This was shot through a G20sf, with a 6" KKM barrel and a 22lb spring.
New Starline brass
CCI-350 primers
Seated to 1.260"
Crimped to ~.422"
200gn hardcast TC/FP from Bulletworks




9.2gns of 800x - Not much in signs of pressure; maybe a little bit of flattening on the primers, but, no bulging or ejector scrapes.  Spread was still close to 50fps, but, this wasn't bad.


9.4gns of 800x is looking good, but with some pressure signs.  Primers were flattening out.  Extreme spread is <20fps.


9.6gn is really nice 1,350fps.  Primers were noticeably flatter, rims were getting really chewed up by the extractor, and bulges appearing ever so slightly.  Brass was all falling pretty much in the same 4 o'clock spot.  A couple of pieces of brass on this string did go to my 6 o'clock.

Nice average of 1361.16fps and a spread of 19.35fps.
It was at this point, I decided not to try out my loads of 9.8 and 10.0gns of 800x.



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