IMR8208xbr test

Looking at the pressure signs, would you think that having slightly more case capacity would be an advantage with this powder? I know that it is all about accuracy, and that the 6PPC is the king of the hill, but based on what I have read (Thanks to all who have shared.) the thought occurred.

What about the Grendel case. If I remember it is about .070 longer to the the shoulder than the ppc. Differences in diameter, etc are minimal. Might be just the ticket for XBR. But then I have been thinking that the ppc case is a bit over capacity anyway. Maybe shorten it .075 or so. I think about 25-26 grains of 4198 full up to the neck junction would be just about right. Keep the muzzle pressure down. The 6 Beggs is just about the right capacity but I just don't much like the taper on that case. Just me I guess, cause I know it will shoot. I sure have been tempted though as I hate making cases for the ppc.

Donald
 
Anyone tried Reloader 10x in the 6 Beggs?

Jerry Sharrett has been telling me that the 6PPC is oversized for current powders since I first started talking to him...
 
I did another experiment with XBR today out of curiosity. It was a powder thrower test. One thing I noticed right away was how easily XBR goes through the thrower. Out of 26 charges, only one gave me a kernel cutting hangup. That's much better than N133.

The downside to XBR I saw was that it did not incrementally increase with a corresponding increase in settings. I tried going up and down three times on the settings to verify the data and it came up the same each time so I don't think it was a fluke. I'd be curious if anyone else has seen this yet?

For instance, 54 clicks on my Harrells PRemium measure gave 31.6 grain charge. And 54.5 clicks also gave 31.6 grains. Then, 51.5 clicks gave 30.0 grains as did 52 clicks on occasion. I have never seen N133 do this. On my measure, one click equals one tenth of a grain all the way from 50 clicks to 55 clicks. It is very consistent this way. With XBR, it went .1 for each click on some numbers and .15 grains per click on other numbers. Sometimes it was even more or even less.

It also gave as much as .3 variation from throw to throw on the same setting but I chalk that up to throwing powder only into one case and breaking my rhythm each throw. Under normal loading conditions, N133 gives only .1 grain variations in my thrower. Very interesting. More testing is in order.

But for now, the numbers I came up with on average were as follows:

51.5 clicks=30 grains
52.0 clicks=30.1 grains
52.5 clicks=30.5 grains
53 clicks=30.9 grains
53.5 clicks=31.1 grains
54 clicks=31.6 grains
54.5 clicks=31.6 grains
 
I shot these groups w/ the new powder

BAT/Krieger14/Wolf and Fed primers/ Bishop 65 gr. bullets.
 

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54, 54.5 clicks the same weight ? 51.5, 52clicks .1 gr apart ? 53.5, 54= .5 gr spread. Lots of variation in the click/weight relationship
 
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Don

If one shoots through a piece of newspaper first, the powder burns will be filtered first. These were the Bishop/Libby bullets that Tom set the world record with at St. Louis. They very well may be the ugliest bullet ever made....but they shoot.

I shot these 5, 3-shot groups consecutively, then stopped and let my friends try their luck. After returning to the bench I shot a 2 and 1 that measured a 0.223. I had 4 rounds left so I shot 1 fouler and a .055. I guess that 6 zeroes out of 7 groups is not too bad for an ugly bullet and a new powder. Let me add that 3-shot groups are much easier to shoot zeroes with than are 5-shot groups.

As far as equipment, I used my old BAT model B and a Krieger 14 twist that had 583 rounds when I started. There seemed to be no difference in the Wolf and the Federal primers. The charges were not weighed but thrown through a Hensler measure. I am really excited about this new 8208 XBR. James

PS: The conditions were NOT perfect. It was very cool and the wind was from 2 to three o'clock and got stronger as the day went on. I used a 36X Sightron scope with the nylon screws throughout this test. I tried to chronograph the loads, but due to being very overcast, the chrono was "acting a fool" as we say down south. I plan to break in a new Bartlein 14 twist in 6PPC and a Bartlein 8.25 to 7.75 gain twist in my Dasher today. James
 
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