38-55 with H4227 and/or Unique

[Yooper003]

I did not mean to hijack this thread, just seen the 38/55 & jumped in.this cartridge is the most interesting & time consuming I have loaded to date. Lengths ,sizes & case dimensions all over the place.

[Dom]

Marlin Cowboy, 24" bbl. All bullets sized 379. Saeco 250gr PB,12grs Win 540/HS-6 with Dacron over powder, 1358 fps.
LBT 250gr GC, 20grs 2400, Dacron over powder, 1688 fps. Both these loads produce fine accuracy in my rifle. Both bullets cast of straight scrap WW.

[woody1]

Specific to IMR 4227, older Lyman manuals have listed loads ranging from about 16 to 22 grains with cast boolits to about 265 grains. Regards, Woody

[GARD72977]

Well interesting results at the range today.

Had a few rounds loaded up with the 260gr, bore is .376 so boolit is .379. Starline short brass, boolit seated to crimp groove just engages the rifling, feeds/cycles fine.

17gr 4227 shot ok, mild recoil accuracy wasn't amazing but first rounds so getting used to the rifle, adjusting sights etc.

Then tried the 10gr of Unique. Definitely a much milder round, quiet too. Accuracy was nothing special but the weird thing was some of the boolits hit the target perfectly sideways. At 50 yards the paper was cut in a jagged profile of the boolit.

I thought keyholing is usually a weight/length issue or an undersized boolit- neither of those really fit here.

Thoughts?

I would check the bore for heavy leading.

[mattri]

No leading, same boolit pushed to 1550 shot very well, as described above.