My gas gun load development
#22
Wild but somewhat expected results from the range today. We are definitely getting the cooler weather that I anticipate my shooting course is going to be taking place in at the end of the month. Today was clear skies and sunshine but I was shooting at around 45 degrees F with a new twist, a large amount of wind. Luckily for my sake I was only shooting at 100 yards so the wind had little to no impact. The 45 degree weather was what a I really wanted to explore with my newly developed load. 

   Here’s the three things I was going after on this range visit. I wanted to once again and more fairly match the Berger 109’s against the Barnes 112 gr bullets as well as dig a little further into LEVR by doing a seating depth string. 

    As far as the matchup fight between Berger and Barnes. The Bergers took a brutal beat down. Sadly this could be my mistake as I can’t confirm that they were all loaded to the same CBTO. They both shot over 1 MOA so either I didn’t do it, or forgot to write it down on my notepaper so I can’t record it anyways. Sorry, did I mention earlier I’m new at this? Very surprised at this. The Barnes however acted like I had a bolt gun and crushed it at .28 MOA. See Pictures. The pic shown with the flyer would measure .69 MOA with it included. The second group leaves very little doubt in my head about the results. Average velocity for the Bergers was 2470 and the Barnes chugged along at 2454. Both of them used W748 at 27.1 gr, BR4 primer, and Starline brass. I haven’t stated this yet but I might as well get it out since I’ll be more specific with my load this time around. THESE LOADS HAVE NOT BEEN PRESSURE TESTED AND COULD BE DANGEROUS. Attempting to make and use this load could result in death. 

    The LEVR seating depth was a little disappointing. I think mainly because the only powder charges Im interested in are the ones that can offer a substantial benefit over W748. I have yet to find a powder charge with it that gives low ES/SD’s. I used Star brass with 29.2 gr and Barnes 112 gr for all of my loads since it was close to what Dino and others have recommended. I shot two separate three shot groups for each of the 5 different seating depths I wanted to try out. LEVR offered no benefit once again for reducing my ES/SD’s however I was able to find out where my barrel likes the CBTO. Two separate seating depths tied and were set at 1.564 and 1.604”. They could only produce .75 MOA so still not getting anywhere with this powder but I was able to see for myself how changing this one measurement brought it down from well over an inch at the start.

    When I reviewed everything later I also noticed that my .28” group using the W748 and Barnes had by complete coincidence a CBTO set at 1.6165” (too close to the best seating depths I just mentioned above). Seems like I’m really dialing in now but further testing should confirm.

    Here’s where things get a bit strange. The consistency for velocity in both powders were both terrible. I wanted to blame the high SD with the Bergers partially for the terrible group  and for the LEVR powder in general. In my previous range sessions my Sd’s were very low most of the time with W748 at least on the warmer days. One day was ES =12 SD = 6 for example. However today was the exception with one of the five shot groups giving me an ES of 45 fps! I’m baffled how this produced the tightest group I’ve ever shot but for now I’ll take it. 

   All in all very happy with my build now. Still a little nervous about getting reliable results but at this point my groups seem to only be shrinking. Work is going into the slow season so maybe Ill be able to report back soon.  Sleepy Sleepy

EDIT: Machine won't let me upload photos. It's telling me they're too large of a file even after PDF'ing. I'll try later if I remember.
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Messages In This Thread
My gas gun load development - by Burt Gummer - 09-25-2022, 10:35 PM
RE: My gas gun load development - by grayfox - 09-26-2022, 01:42 AM
RE: My gas gun load development - by Burt Gummer - 09-26-2022, 02:32 AM
RE: My gas gun load development - by CZ527 Guy - 09-26-2022, 02:28 AM
RE: My gas gun load development - by Thelaststraw - 09-30-2022, 08:18 PM
RE: My gas gun load development - by Burt Gummer - 10-04-2022, 11:06 PM
RE: My gas gun load development - by Dino11 - 10-02-2022, 09:04 PM
RE: My gas gun load development - by Dino11 - 10-05-2022, 09:06 AM
RE: My gas gun load development - by Burt Gummer - 10-05-2022, 05:23 PM
RE: My gas gun load development - by Dino11 - 10-05-2022, 09:56 PM
RE: My gas gun load development - by Burt Gummer - 10-06-2022, 01:00 AM
RE: My gas gun load development - by IALoder - 10-06-2022, 07:43 PM
RE: My gas gun load development - by Burt Gummer - 10-07-2022, 12:43 AM
RE: My gas gun load development - by Burt Gummer - 10-08-2022, 09:19 PM
RE: My gas gun load development - by Burt Gummer - 10-08-2022, 11:33 PM
RE: My gas gun load development - by GRH - 10-10-2022, 02:09 PM
RE: My gas gun load development - by Burt Gummer - 10-11-2022, 12:27 AM
RE: My gas gun load development - by Dino11 - 10-10-2022, 10:18 PM
RE: My gas gun load development - by Burt Gummer - 10-11-2022, 12:40 AM
RE: My gas gun load development - by GRH - 10-11-2022, 11:55 AM
RE: My gas gun load development - by Burt Gummer - 10-18-2022, 12:47 AM
RE: My gas gun load development - by Dino11 - 10-22-2022, 09:44 AM
RE: My gas gun load development - by Burt Gummer - 10-24-2022, 09:59 PM

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