SHERMAN MEGA LINE

The Hornady brass actually performed better than the Nosler and Nosler is 4 grains short on capacity compared to the ADG brass that will be used! Also, the head size is smaller in the 33 Nosler brass so it over expands which makes things even worse.
^^^ that would explain a hell of a lot more than .. ITS SOFT... 😂
 
Cuz it's soft as a freshly baked chocolate chip cookie
The Hornady brass actually performed better than the 33 Nosler brass plus the Nosler is a full 4 grains short on capacity on the ADG brass for the Mega. Add to that, the smaller base diameter of the Nosler has to over expand which makes the soft brass even worse!
 
Update on the 7 MEGA:
I havent shot for a while now but wanted to get the MEGA ready for elk season. I had good results at 100 yards around 3170' with a 175 EH so wanted to run a ladder to see where I really was.
I was using formed wsm brass so my necks were about .070" too short but until I get brass, its the best ive got.
I loaded up 6 loads of N570, 2 each, from 73.8 to 75.3 in .3 grain increments. I found a spot at 357 yards on an old logging road where I could use my bipod and a shot bag rest and went to work.
I have no idea what the first 2 shots were all about but chalked it up as an anomaly for now. My shooting position was a little sketchy so could have been that? You can easily see the major jump from 74.4 to 74.7 with 2 distinct nodes. I havent done a Satterlee yet but earlier chrono data puts me at 3170 high and at 3100 low.
4 of the 6 shots went into .14" moa so pretty encouraging especially at those speeds. I have 6 firings now on that brass and primer pockets are nice and tight!
No pressure signs at 3170. No heavy bolt, extractor marks, etc. The highest I ran earlier was 3211' with nothing there either but it has to be about there!
Actually, more than I hoped for!
Testing on the 300 has not started, but soon, and the 338 ran into some build issues, so nothing there either. I think this 7 is going to be a real eye opener and I have reamers for both the LA and Medium length versions
 

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Update on the 7 MEGA:
I havent shot for a while now but wanted to get the MEGA ready for elk season. I had good results at 100 yards around 3170' with a 175 EH so wanted to run a ladder to see where I really was.
I was using formed wsm brass so my necks were about .070" too short but until I get brass, its the best ive got.
I loaded up 6 loads of N570, 2 each, from 73.8 to 75.3 in .3 grain increments. I found a spot at 357 yards on an old logging road where I could use my bipod and a shot bag rest and went to work.
I have no idea what the first 2 shots were all about but chalked it up as an anomaly for now. My shooting position was a little sketchy so could have been that? You can easily see the major jump from 74.4 to 74.7 with 2 distinct nodes. I havent done a Satterlee yet but earlier chrono data puts me at 3170 high and at 3100 low.
4 of the 6 shots went into .14" moa so pretty encouraging especially at those speeds. I have 6 firings now on that brass and primer pockets are nice and tight!
No pressure signs at 3170. No heavy bolt, extractor marks, etc. The highest I ran earlier was 3211' with nothing there either but it has to be about there!
Actually, more than I hoped for!
Testing on the 300 has not started, but soon, and the 338 ran into some build issues, so nothing there either. I think this 7 is going to be a real eye opener and I have reamers for both the LA and Medium length versions
Here is a Satterlee I ran today to see how it matched with the ladder.
I love it when it comes together this way.
Note the big jump in elevation from 74.4-74.7 (shots 2-3)coincides with large velocity increase and then flat spot at the high ladder node (shots 3+) Velocity sped up about 10' since last chrono. But I think its settled in now and I can hunt.
I shot 3 at 74.9 and 3180 for group when I was done. Now to play with seating depth a little and i should have a potent long range elk load.
No pressure signs yet at 3205'.
7 firings now on the brass.
 

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At a given chamber pressure, the bigger the boiler, the more steam. The more steam the more energy produced. But maximum chamber pressure must not be exceeded and when using larger capacity case in relation to the the neck diameter the pressure needs regulated or reduced to permit the gas a bit longer to escape the smaller neck or exit. Example: a 30-06 will propel a 120 grain bullet 3400 fps. The very same case, necked down to 25 caliber in a 25-06 will only propel a 120 grain bullet to 3100 fps.
Thank you for reminding all of us or this fact
 
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