17 Fireball

[coyote222]

I should be getting my 17 Fireball MGM Contender rifle barrel in a couple of weeks. I have CFE BLK powder, Berger 25 gr bullets, and CCI 450 primers on hand. Anyone loading the FB using these components? I have read that CFE BLK works best with 20 gr bullets. I guess because of a higher load density. 85% load density for 20 gr bullets vs 75% load density for 25 gr bullets. Any help would be appreciated.

 

[Jason D Hostetter]

CFE BLK isn't particularly sensitive to case fill, it gives the highest velocity in the small 17s. If you want good case fill and better SDs, I suggest VV N120 or RL7, with H4198 coming in behind those, if you can find it. For a ball powder with good case fill and velocity, AA2200 is what you want to look at. 450s work, but aren't necessary with sub 20grn charges, especially with the extruded powders.

 

[snert]

^^^^
This

 

[SD guy]

I have not used CFE BLK in the 17 FB. If it were me, IMR 8208 XBR, would be the first propellant I would try with the Berger 25's. I would be more confident with the CFE BLK with 20 grain projectiles & lighter. Bench Rest & IMR 8208 had been my favorite propellants in the 17 FB YMMV.

Suppose you can give it a try just may work rather well.

Jasons recommendations have merit as well.

 

[coyote222]

Thanks for the info. I'll post when I have some results.

 

[swd]

When I shot 17MK4 which is essentially the same cartridge, H335 was outstanding. 20gr V Max's at 4250. A lot of MK4 shooters use H335.

 

[ArtinNC]

When I shot 17MK4 which is essentially the same cartridge, H335 was outstanding. 20gr V Max's at 4250. A lot of MK4 shooters use H335.

^^^^ My favorite load .

 

[hogpatrol]

When I shot 17MK4 which is essentially the same cartridge, H335 was outstanding. 20gr V Max's at 4250. A lot of MK4 shooters use H335.

Yep, I had used VV133 for years before trying H335 and the results were the same and a lot cheaper. Benchmark worked good with the 30s. As previously posted, 450s aren't really needed. I use BR4s.

 

[coyote222]

I tried LT30 in the fireball 0.6 grain from starting load I had flattened and pierced primers. MGM said the gun had too much head space. It was 0.008, twice what It should be. I shimmed the breech plate to less than 0.001 head space. Starting load with LT30 flattened primers. Then I used CFE BLK which has a slower burn than LT30. Starting load had normal looking primers, but the primers soon started flattening. I ordered some IMR4198 which is several powders down on the burn rate chart. I know powders on the chart are in order of relative burn rate and are not in fixed rates for each powder. The CFE BLK gave one 3 shot group of 7/8 in and one 3 shot group of 5/8 in at 100 yds.