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View Full Version : 223 AI - H4895, Benchmark, & XBR8208 load workup - MORE added



dcloco
06-11-2010, 01:22 AM
Just some initial testing. VERY cloudy day, so no chronograph readings.

These loads are for a 223 Ackley Improved chamber - do NOT try these loads in your 223!!!!!!!!

Using a 53 gr HP flat base Hornady Match bullet (never shot in this barrel previously), CCI450's, & Lapua brass previously fireformed.

Top left - 8 shots of H4895 0.1 grain increase of powder per shot 27.1 to 27.8 Previously chronographed loads in this barrel put the speeds in the 3600+ area.

Top middle and right - 5 shots each target of Benchmark. The node for Benchmark tends to be in the 27.4 to 27.7 area in all of my barrels. Previously chronographed loads in this barrel put the speeds in the 3600+ area.

Bottom left and middle - beginning loads of XBR8208. As you can tell by the POA (point of aim), the beginning loads for XBR8208 is slow in comparison, but is definitely coming up as the powder charge increases.

Bottom right - this is a fireform load I use. Very good accuracy when fireforming brass!!

Next time out, I will shoot the loads over the chronograph to collect the data.

http://img.photobucket.com/albums/v245/dcloco/223aiBull.jpg

82boy
06-11-2010, 08:37 PM
Here is a question I get all the time.
Do you think the 8208XBR is dirty?
My experience with it has been great and I can not say that it is any dirtier than any other powder N133, H322. but I have been asked this a lot, and other people believe that it is.

dcloco
06-11-2010, 09:10 PM
I agree with you.

Kind of funny on the groups I shot. The L/R stringing is barrel/bullet. But this proves, how a barrel reacts when shot. As a person finds the real accuracy node, the groups really tighten up.

Have to bump the load more with the XBR, judging from the point of aim, it is not as fast as the H4895 or Benchmark loads.

Of note, the barrel used above...is a 1.250" straight shank in the 28" variety....so...the rifle does not move when fired.

Next groups will be fired with 52 gr HPBT's. This barrel just loves them.

82boy
06-11-2010, 09:23 PM
I will say I am impressed with XBR, I hope they keep making it, it sure did wake up my old Krieger barrel on my Savage, and I have a hard time seeing a difference with it and N133 on my Bat with a Brux barrel.

I will say this I have played with the old IMR 8208, and the new stuff at the same time, and they are as different as night and day. The old IMR meters different. You can only get a little over 30 gr max in a PPC case. The XBR will go 32 grs. The old stuff seems to be much faster burn rate. It seamed that I could not get enough XBR in a PPC case to cause a pressure sign, not true with the old IMR. (I could get pressure signs at a hair over 29 grs)

dcloco
06-14-2010, 02:00 AM
More load workup tonight. Pushed the XBR a little harder and added Ramshot TAC to the lineup.

The chrono info is what it is. Loading with a beam scale, not the Acculab. When I bring the Acculab here, will run the loads again. Obviously, have some issues. At these powder charges, the 223 AI cases are VERY full. Might be able to squeeze a touch more in there. NO pressure signs on any of the charges in this barrel.

Mislabled the second group. Should read XBR8208 for the 27.0 to 27.4 powder charge.
http://img.photobucket.com/albums/v245/dcloco/pXBR8208.jpg
3481 3455 3489 3486 3537 3519 3522 3584 3602 3579
http://img.photobucket.com/albums/v245/dcloco/pTAC.jpg
3506 3533 3531 3535 3557 3579 3562 3573 3595 3655
http://img.photobucket.com/albums/v245/dcloco/pH4895.jpg
3546 3541 3551 3595 3614 3525 3624 3630 3652
http://img.photobucket.com/albums/v245/dcloco/pBenchmark.jpg
3601 3636 3581 3608 3628

possum1
06-14-2010, 03:14 PM
What yardage you using on this test ?

dcloco
06-14-2010, 11:30 PM
What yardage you using on this test ?


Only 100. Just wanted some baseline testing for XBR8208 and TAC. Two powders that I have never tried before. Have shot H4895 and Benchmark extensively and knew what to expect.

Funny thing is, guess I will have to start weighing bullets and using a comparator....besides bringing the best scale I own to weight charges with.

Budweiser360
06-25-2010, 11:39 AM
You seem to have a high amount of ES and SD in these loads, what kind of scale are you using?

dcloco
06-26-2010, 12:22 AM
You seem to have a high amount of ES and SD in these loads, what kind of scale are you using?


There is a huge amount. OLD RCBS and a junk digital. I use the digital to get me close and finish on the OLD scale.

Not even close.