11-03-2022, 09:51 PM
Hollis Wrote:I saw that same data and slowly worked up to 28.7 and saw no problems. I had 29gr load on hand to try if only no pressure signs at 28.7. All looked good so I went ahead and shot it with no serious signs of overpressure. The primer was not as rounded, but not flat, and there was a very slight mark from the ejector on one of the rounds but not the other two. So, it looks good for me but I DO NOT RECOMMEND this load for anyone who doesn't take all precautions regarding safety in load development procedures.My experience...after reading this thread, I proceeded to work up a load with H335 powder for one of my AR Grendels with 20 ss bbl; original new Lapua brass, Hornady 123gr SST, CCI 450 primer, 2.25 OAL, starting load: 27.5gr H335,#2: 27.8gr, #3: 28.1gr, #4: 28.4gr, #5: 28.7gr. The first shot with 28.4gr blew the 5rd mag apart and out of the rifle! The 27.5gr was the only load that functioned properly...the remaining loads did not pick up from the mag. although they seemed to fire ok, all 5 shot groups were under an inch.
I have 20" Group Buy barrel in semi-auto AR15 platform.
The moral of this experience...NEVER USE OTHERS LOADS, ALWAYS use Published starting and MAX loads when working up a new load in a new firearm! (I have been reloading since 1968...THIS was my first experience with a blown stuck case.) ALWAYS USE PUBLISHED PRINTED LOADS WHEN WORKING UP NEW LOADS.

