This new powder finally hit the local store shelves. Great to work with, it looks like micro-sized Varget. Loaded a series of proofs for the .204, and will follow with a range of charges for an OCW test.
This stuff is so nice to work with, I may keep buying it even if the accuracy isn't quite as good as my favorite loads (25.6 gr IMR 3031 behind a 39gr Sierra Blitz King with CCI 450 primers - at 3910 fps and 0.2" groups and better at 125 yds)
I'll let you know how the 8208 shoots.
My neighbor is working up loads for his .223 also. Anyone out there had a chance to try this stuff yet? It's supposed to give consistent results from temps well below freezing to scorching, with a burn profile designed for cartridges like the .223 - according to the hype.

(FINALLY got my hands on some Fed 215 primers for my WBY, too. WoooHooo!!!)

44, interested in your results. Keep us posted!

You have to remember that the "gun rags" are enthusiastic about every new thing that comes out probably because the articles are essentially paid advertising. That said, I believe the powder to have good potential but can say nothing yet about temperature sensitivity. It does meter very well.

Grumulkin, do you have a velocity on that load? My 130gr 270 loads are using about 55gr of IMR4350. There's another savings/advantage with the IMR8208 if you are getting around 3000 fps with only 43.5gr.

I confess, I haven't yet checked the velocity but probably will next week.

Quite a nice group at any velocity!

Nice shooting.

Well, I fired the proof rounds today. I started getting primers cratered around the firing pin at only 0.5 gr over the starting load, so I'm not sure how I will continue. The primers were not excessively flattened, and the cratering didn't get any worse until the Max load. At the Max, the primers did show flattening. I have not yet reprimed the cases, so I am not sure yet at which point the primer pockets started to enlarge, if at all.
(Note: I do not get cratering with my Max load of 25.6gr IMR 3031, a compressed load with new unfired Win brass - about 99% filled in fire formed brass. Both the compressed loads in the new brass and the loads in fire formed brass chronograph exactly the same, which surprised me, . . .but that's another story. This load also groups amazingly well in Nosler brass.)

The components:
IMR 8208XBR powder, once-fired and neck sized Nosler brass, CCI 450 primer, 39gr Sierra blitz King bullet. Fired in a Ruger 77 Mark II target/varmint off-the-shelf rifle. I would NOT RECOMMEND loads this hot with a Ruger 77 Hawkeye rifle.

The results:
grains powder fps velocity
26.0 3693

26.5 3864

26.8 3938
3930

27.1 3951 (one round did not register)

27.4 4020
4037

27.7 4042
4073

27.9 4137

The loads listed by Hodgdon, for a 40gr Hornady VMax, give a starting load of 26.0gr (at 3586 fps) with a Max load of 27.3gr (at 3754 fps). They used Federal 205M primers, which are about equal to the CCI 450's that I used (the Rem 7 1/2 BR primers are not as hot, usually averaging around 60 fps slower than the CCI 450's.) The Hodgdon data used Hornady brass.

Comparing the 39gr Sierra loads with listed loads for the 40gr bullets, I have been finding that for the half dozen powders I have previously loaded it is safe in my rifle to go 0.3gr to 0.6gr above the Max listed for 40gr bullets when loading the 39gr Sierras.

My daughters are arriving tomorrow AM with their husbands for a 3-day visit. As they are into action pistol shooting, it is unlikely that I will have the rifles out until next week. Accuracy testing will have to wait.

Sorry, no data for the .223 yet.

44marty wrote:

it is unlikely that I will have the rifles out until next week. Accuracy testing will have to wait.

Only waiting a week to get back out to the range? Life doesn't get much better than that! I'm lucky if I can bet back out a month later.

44marty, I thought I had an answer to your primer cratering issue !!!

After re-reading I realized you are using CCI 450's not the 400's but I decided to comment on it anyways to possibly help others.

CCI 400, Federal 200, and Remington 6 1/2's have thinner cups than other small rifle primers. These were designed for lower pressure applications such as the 22 Hornet. When used in conjunction with cartridges such as the 204 cratering will occur rather quickly.

Just food for thought to keep in mind when choosing small rifle primers.
Large rifle primers have the same cup thickness.

Only waiting a week to get back out to the range? Life doesn't get much better than that! I'm lucky if I can bet back out a month later.

Slim, no luck involved here - I moved here because I can shoot handguns from my porch and rifles in the back yard. I'm limited to 125 yards, though, because of the terrain.

Chrono results for the 8208 FROZEN ( -10 deg F for 24 hrs) and at 75 degrees were nearly identical:
FROZEN
3836
3880
3820
3896
3848

75 F
3828
3884
3892
3872
3868
3900
These were with 26.8 gr IMR 8208 in neck-sized Win brass, Rem 7 1/2 BR primers, pushing 39 gr Sierra blitz king bullets.

The primer cratering issue was the same with the Remington primers and Winchester brass as with the CCI 450 primers in Nosler brass.

I tried OCW testing in two groups, and outsmarted myself. I'll have to fire one more set of OCW rounds, for which I hope to have chrono data. The clouds got dark enough yesterday to shut down my chrono, so I have no info for the velocities I was getting.
I outsmarted myself by looking for a "low" OCW charge and a "high" one. The results hint that the best charge will be found somewhere between the two groups that I tried.

I loaded from 26.2 gr down to 25.4 gr of powder, looking for a cheap plinking round.
I made up rounds from 26.6 gr up to 27.4 gr of 8208, hoping for an accurate hunting/long range load.

Loads were increased in 0.2 gr increments.

The 26.2 gr and 26.6 gr loads were the only ones having close to the same point of impact. As loads were lighter, they moved left and down. As loads ranged hotter, they moved right and slightly up and groups got larger.

NEXT: 26.2 to 26.6 in Win brass with Rem primers, with chrono data, should give me my best .204 load for this powder and ballisitcs for it.

I don't know if you can make out the primer issue in the photo. The deformation isn't severe, but looks like it could cause firing pin wear/damage over time.

HMmmmmm - Do I have to attach the photos first, and then add the text? I'll try to post photos . . . .

Well, I uploaded photos but don't see the URL displayed to link them to my message. Old dogs learn new tricks SLOWLY (and then promptly forget them).
The primers are shown in the "misc" folder. Also posted some favorite targets in the guns/targets folder. One of these is an almost acceptable group from 8208 powder - the next OCW test will tell the story.

I will also have to try the "Frozen ammo" test with IMR 4895 and IMR 3031, which are my go-to powders for the .204

44marty wrote:

Well, I uploaded photos but don't see the URL displayed to link them to my message.

You can not link to any photo's you post on HuntingNut even though it suggests you can. Use photobucket.com. Very easy to use even for old dogs like us.

44marty wrote:

Well, I uploaded photos but don't see the URL displayed to link them to my message. Old dogs learn new tricks SLOWLY (and then promptly forget them). The primers are shown in the "misc" folder. Also posted some favorite targets in the guns/targets folder. One of these is an almost acceptable group from 8208 powder - the next OCW test will tell the story. I will also have to try the "Frozen ammo" test with IMR 4895 and IMR 3031, which are my go-to powders for the .204

Hope this helps

Not sure witch ones your trying to post but here's the one with the primers

and your best group

should have stopped with a 3-shot group!!!

Slim, I actually did stop with three rounds. I doubted what I was seeing through my scope and held the fourth round slightly low and left to make sure the bullets were actually hitting the paper. Kind of ruined the look of the group, though. Also, I wish the scope had been sighted in first. It would have looked much better on the X. This group was at 125 yards.

Thanks, Joe, for posting the photos. Slim, I'll try photobucket next time. I'm on my way out to shoot some more 8208 loads this afternoon.

That "best group" photo was with IMR 3031 powder (26.5 gr) pushing Hornady 32 gr VMax bullets out of unfired factory new Win brass with CCI 450 primers. On average, I find my rifle more accurate shooting 39 gr Sierra blitz kings. The 32 gr bullets drift more with the wind, though they shoot a bit flatter (at 4000 to 4100 fps).