Recently acquired a Marlin 93 38-55. After getting it into working order, I started looking for brass and can't to seem to find any so I decided to use 30-30 brass. I found you can purchase a .375 raptor (308 necked up to .375) expander/decapper pin from Lee and it works quite well in the 38-55 sizing die to convert 30-30 brass to 38-55. The .375 H&H expander will work also, but it is really too long and I had to cut the tip off of it to work. The Raptor still allows for use of the decapper function. It doesn't completely stretch out the case (beyond the ball), but gets it close enough to load and gives MOD (minute of deer) accuracy instead of wasting primers "fire forming" brass with some sort of wad and powder.
I slugged my bore and am getting .379. I am using the Lee 250 grain mold and powder coating which they mic around .381-.382 and .380 sizing dies evens it all up. I tried chambering without sizing, it won't go in. Sized, it slides right in.
The 30-30 brass comes in around 1.900" (using winchester) or so when converted which is a tad shorter than I wanted. I checked a boolit in my gun and the max OAL touching the lands is 2.472" with the sized boolit. The boolit nose to crimp groove is approx .425". So to utilize the crimp groove and have the boolit touching the lands, that puts my case length of 2.047" roughly. So that means either the long or short factory brass will be too long for my purposes unless I seat the boolit past the crimp groove.
Testing loads using my die formed brass, I used RL7 from 25-27 grains with a OAL of approx 2.410". At 25 yards, I had 2 touching (same hole) with the 26 grain load and one about 1" away. Granted it was a very poor bench setup. I will have to do better next time. So not sure if the accuracy was user error or equipment. The brass looks good after fire forming and even showed signs of low pressure with the primer being backed out, same thing I see in 30-30 loads. More grip in chamber than case head force to reseat after firing. The load chronographed around 1700 FPS. I may try some loads with H4198 and see how that goes.
I did order a .379 Lee type expander plug (and a .377 just in case) from Track of the Wolf to expand the mouth and did some tweeking to have it expand just to the point the boolit will seat to and used the powder thru expander included in the Lee die set to bell the case mouth in the powder stage. I wished Track of the Wolf would drill out those plugs so they could be used as powder thru.
Now, I can use 38-55 short brass and trim so I can use the crimp groove, which someone suggested in another post. Or I can seat my boolit close to the lands and ignore the crimp groove, which will work with either converted brass or short brass. Not real sure the 38-55 long brass will work for my purposes, but guess if I can get my hands on it, I can give it a try. I do have the Lee factory crimp die which is the collet type and really doesn't use the crimp groove at all, but I kind of want to use the groove so the mouth of the case will be recessed to ease chambering.
I do need to load up some more rounds and do testing at 50 yards off a better rest setup. Not sure if the "fire formed" brass will show a marked improvement in accuracy (maybe consistency) over the die formed brass or not.
Yes, I still need to do a chamber cast with my cerrosafe and see exactly what it looks like, that is on my to do list.
This has actually been a quite an enjoyable endeavor. Never had to do so much to be able to shoot a gun, but it is satisfying.
Suggestions, thoughts, comments?
Rosewood
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