[Brian Carlson]

A friend of mine is having troubles with his seating die. I have not been over to his place to check out his setup. Maybe some of you can diagnose the problem. He reloads for his 270 rifle and for his 357 magnum revolver without any problem but when he seats bullets in his 38-55 Winchester they bulge the case on one side. The case does not buckle but it bulges, like the bullet is not properly centered. The cases are so badly bulged that he cannot chamber them in his Marlin 336 Cowboy rifle. He has run new cases through his sizing die and then belled them and then seated the bullets (he has tried both a Lee and an RCBS seating die. Both new dies cause this problem. He is confident that he is using the correct shell holder. Any ideas what could be the problem? The bullet he is trying to seat is the Laser Cast (from Oregon Trails Bullet Co.) 240 RNFP. He thinks the problem might be that the seater plug is coned/dished out like for conical bullets but his bullets have a flat point and so maybe the seater plug is forcing the bullet to tip as it is being seated. Could that cause this problem? He said his bullets have a diameter of 0.380” which apparently is the correct diameter for the 38-55. Thanks, Brian.

 

[Big Bore]

If the seating stem does not fit the contour of the bullet nose, all kinds of goofy things can result. But I don't think that is the problem.
I looked in my manuals and they list the proper bullet diameter as .375, not .380. Only in the Lyman manual for lead bullet loads for old .38-55 rifles did it list sizing diameters of .377 and .379. Has he slugged his bore to be cerain he is not using a too large a bullet at .380? That would be the first thing I would check. I seem to recall the Marlin used a .375 bore.
I have seen lots of bulges on straight walled cases, such as the .458 Win and .45-70, that never cause a problem. If the bullet measures .380 and is the correct size, the expander should not be smaller than .377. If they used a .375 H&H type expander that measures only .373, then that may make the bulge look more severe than it is, but it should not cause a problem in chambering. These type of bulges do not usually cause difficulty chambering unless really severe as the bulge occurs in an area of the case where usually there is lots of chamber room. But, if he is crimping way too hard, the case can be bulged out from the crimp and that can easily cause problems chambering. If he is giving a heavy crimp, have him back off on the crimp a bit and see what happens.
If none of the above works, he might order a custom seating stem from RCBS. He will need to send 3 bullets, not cartridges, and I think the cost is $11, but I bet that is not the problem. My money goes with the wrong bullet size.

 

[MikeG]

Expander is too small.

Commonly available dies are going to be set up to use 0.375" bullets because that's what you can buy for the most part (in jacketed bullets) for that caliber. His dies might handle 0.376" or maybe even 0.377", but that would be about it.

If the die set was correct for 0.380" bullets, it would expand case mouths so much that 0.375" bullets would literally fall into the cases with no neck tension whatsoever. .38-55 reloading with that large of a bullet is very nearly like going to a completely different cartridge.

Although many .38-55s really need 0.380" bullets, I'm not aware of any specialty die sets that are correct for that size.

I would advise your friend to track down a Lyman "M" die for that caliber. That expander design is the best available. Hopefully, it will expand the case mouth enough to start a 0.380" bullet.

If the standard Lyman "M" expander does not expand the case mouth enough .... let me know and I can turn out a custom-sized expander plug for 0.380" bullets, that will fit an "M" die. I made one for Marshall and he says it works great.

 

[MODEL71]

WELL WELL , this is a topic.
the bulge is of no concern, the fact that the bullet won't fit the chamber , now that is another matter entirely.
many 38-55s have chambers too small for the bores, like old 45 revolvers. if the bore is a 380 its probably a older rifle, in those days small chambers and big bores worked out ok, bullet obturated to fill bore.some of these old guns insist on comprimises. unless you load as in 1899 , expect some limitations, get it shooting as best you can with what you have and enjoy

 

[humpty]

38-55 bulge

I've read that RCBS Cowboy dies are designed for cast bullets, and are of the correct diameter.
Check it out, I do not heve personal experience with this setup.
Humpty

 

[humpty]

38-55 chamber too small

I've also read that the chambers of many rifles are cut for jacketed bullets and may need to be reamed to shoot cast.
I think these subjexcts have been duiscussed on the SASS wire.
Humpty

 

[kidcoltoutlaw]

in one of the old speer manuals they talk about using wax in the seater plug.it will take on the shape of the bullet and hold it steady .it might work till you can get a seater cut to fit the bullet.like others have said check the expander size.i had one for an 06 one time was to big the bullets could be pulled out with your fingers after you seated them.i polished it down about .0005 and it worked great,thanks,keith

 

[MikeG]

I hadn't thought about the chamber being too small for big cast bullets. That's easy to check.

Take a case that has been fired in that gun, and see if one of the 0.380" bullets will slip into the case mouth with very little pressure. If not....likely the chamber is too small and/or the brass is too thick. Either the brass needs to be reamed / neck turned, or the chamber needs to be opened up.

Or, fire-form some brass from .30-30, and see if that yields thinner necks (it should).

 

[humpty]

Wax in seating die

I think wax in the seater plug would have the potential to get 2 bullets in a case.
Some cowboy shooters did this, using a dillon. They blew up 3 AWA single actions before they figured out what was casuing the problem.
Humpty

 

[kidcoltoutlaw]

the wax just lets the plug take on the shape of the bullet.i did it for a while in a .44 mag till i got a plug to fit the bullet.looks like the cowboy lite loads would cause the pressure problems.lite loads can cause higher pressure than heavy loads.it came from speer not me any way.give lyman or speer a call they have a great help line,thanks,keith

 

[kidcoltoutlaw]

i was also using a single stage press at the time i used the wax,thanks,keith

 

[Swany]

Bulge in cases

Brian, if you have lee dies which I suspect, back off your sizer .100 (I have backed off mine more)the sizer is made for a .375 win not the 38-55 though it will work for both basically you are sized down too far for the 38-55 this will take care of the bulge the next firing, now for the crazy part take out your decapper and very slightly resize the case with a bullet in it trying it in your rifle until it fits the chamber and test them and see if they shoot ok, know of another with the same problem on the Marlin Talk thread says this works, another thing just in case you have a case crunch once in a while, take out your expander and file a more generous lead on it. I have a 38-55CB and shoot cast bullets .379 my bore measures .3785 but they seem to shoot quite well, in mine. Take care and have fun. Swany