Author Topic: RCBS Cowboy dies for the .38/55 (Read 675 times)

Badnews Bob · « **on:** April 22, 2005, 06:44:43 PM »

I got them in the mail Wed. But didn't get to play with them until today, I think they may cure some of my problems loading .38/55.

First off they look pretty, Case hardened with brass rings, But the best part is the belling die. It comes with two expanders, one is .376 dia the other is .379 dia. The die has a pilot plug before the bell which opens up the case mouth to just below bullet seating depth, (with 250gr cast) to .376 or .379. It bulges the case but now it nice and centered not off to one side like before, Thats good but... They still stick in the chamber.

This may be alright as my rifle has always ejected empties even if they stuck while unfired, I'll need to get to the range with some rounds to test this, Also a little chamber polishing may help. I've not polished the chamber.

Everything looks better I just need to load up and light some off, I'll let you know soon.

Mac11700 · « **Reply #1 on:** April 22, 2005, 07:52:46 PM »

Sounds good...keep us posted as to your results with your handloads...

Mac

Haywire Haywood · « **Reply #2 on:** April 23, 2005, 03:28:05 AM »

Sounds like the 38-55s need a custom finish reamer that opens up the chamber just a hair to meet the need the larger bore presents. Then once you fireform to it, just neck or partial-full size your cases.

Ian

cheatermk3 · « **Reply #3 on:** April 23, 2005, 05:25:55 PM »

Bob, if fired cases eject freely, and live rounds stick, the problem almost certainly must be alignment. Even though the bulge looks to be nice and even, it still could be off-center enough to cause it to stick in the chamber, unless they're long enough that the bullet is into the rifling? Have you tried running the loaded rounds back into the sizing die? If you still have the other set you could try it and leave it set up to just straighten it enough to chamber freely and extract/eject a live round.

I've found that, using .380" cast bullets in my gun, a fired case needs no resizing to have enough tension to hold the new bullet. Most rounds made this way show a minimal bulge, or none, but they have from 11-18 thousandths runout, as shown on my RCBS fixture. At this point they will almost chamber freely, need a bit of arm to close the action, and a few light taps with a rod to get them out.

After a bit of trial-and-error, I found a setting for the sizing die that allows free chambering and ejection of these rounds. This setup reduces the runout to 0-4 thousandths, and reduces the diameter by .002"(thanks again for the tip JPH45).

I still haven't got all the bugs out yet but I need to get ahold of a new batch of cases and start over, since I've pretty well muddled up the batch I'm now using. But even so, I'm shooting into 3/4" at 50 with fliers opening it up to 3".

I ain't givin' up yet.

Badnews Bob · « **Reply #4 on:** April 23, 2005, 06:33:43 PM »

I still believe the chamber is cut for .375, I don't have a runout gauge so I can't check that. It will chamber .378 dia bullets no problem but they are too small for my bore.

I am haveing to work this weekend so I don't have the time to do much but I will later this week and can maybe get to the range by the weekend.

I hope the weather is better than tonight..... Its snowing cats and dogs out there! :shock:

No giving up here, I know I can figgure this out.

JPH45 · « **Reply #5 on:** April 24, 2005, 04:12:34 AM »

I once thought that these chambers were made with 375 reamers....not today. I've got a copy of the NRA hardback "Handloading" in the back is a list of cartride and CHAMBER drawings for the 375 and the 38-55. The chamebr should be .401 at the neck for the 375 and should be .3949 (.395) at the nec for the 38-55. If anything, the 38-55 has the tighter chamber. The brass should be .400 at the neck on the 375 and .3922 on the neck for the 38-55.

By these dimensions, if the chamber were true to 375 dimensions, 38-55 sized loads should FALL in, absolutely no resistance.

From this I think what is going on is we have 38-55 chambers, and 375 size loads. It is going to take a cerrosafe cast to find out for sure.

Another problem is with the length of the chambers and brass. The chamebr of the 38-55 should be 2.118 to the start of the throat, the 375 should be 2.080 If the chamber is a 375 chamber and hte brass is true to 38-55 length 2.129.-.020 it won't fit in a 375 chamber, it would stop against the throat and the action wouldn't close.

Others report that over time, Winchester has changed the length of their brass untill it is now all 2.080 regardless if it is 30-30, 375 or 38-55. If this is true, I can only surmise that oncvce the initial drawings are done on these cases, the same trim dies are used to reduce thier tooling costs. Anybody got some Winchester factory 38-55 brass that we can get a length on?

Haywire may be right on, we just need to have a custom reamer made to open our chambers by .002-.003" and be done with it. For my purposes, I don't mind screwing in my sizing die 2 turns and running the loaded cases back in, works fine, as I decap the case with a 45-70 die I'm using like a universal, so I don't have the decap stem in my sizing die and use it at any depth I like. I only turn it in 5 turns to size the brass after firing, I'm only neck sizing and I'm sure that cheatermk3 is right on, that one doesn't even need to size this brass after firing, certainly not with light loads anyway.

riverjackal · « **Reply #6 on:** April 24, 2005, 08:55:59 AM »

JPH45,
I just measured some twice fired 38 55 Winchester untrimmed brass from factory rounds and it measured for 6 cases as follows
1.2.076
2.2.085
3.2.080
4.2.078
5.2.080
6.2.081
I hope this will help.
Happy reloading ! ! !

JPH45 · « **Reply #7 on:** April 24, 2005, 09:55:12 AM »

riverjackel, exactly what we needed and confirms what others have said, Winchester has shortened the length of 38-55 brass over time, most likely to reduce tooling or setup costs, one size fits all. In the end this points to NEF is cutting a very slightly undersize chamber. Could be nice to have a proper size chamber for the bore size, What do you guys think of having a reamer or some kind of lapping tool made???

Badnews Bob · « **Reply #8 on:** April 24, 2005, 02:36:52 PM »

I'm gonna have to do a chamber cast, The one round I have loaded right now is .3977 at the neck. It chambers but its tight, I'll check case sizes and loaded round sizes tommarrow and maybe cast my chamber. I also may try to find some .379 bullets and see what they'll do.

I wonder if just a lead reamer would clean them up enuff?

riverjackal · « **Reply #9 on:** April 25, 2005, 05:02:58 AM »

Bob,
Would you mind to explain what you mean about the lead reamer ? My H&R target model needs some more room for .379 lead bullets to chamber easy.
Appreciate any info.

Badnews Bob · « **Reply #10 on:** April 25, 2005, 03:09:49 PM »

I loaded some rounds today and was very happy with them, RCBS die alone thou finished rounds are around .394 just below the crimp, Two of them chambered easy one didn't, So, I ran them into my Lee sizer die with the decapping rod removed and screwed in so only about half an inch sized, they measured .389 and .390. They fell right in the chamber no sticking at all. I loaded ten, seven resized three not and went and shot them, Off hand they all went into about a 4" group,(I wasn't trying just wanted to see how they worked) They all ejected fine and can see any diffrence in them or how they shot. I'm happy so far, That was with 35grs of IMR 3031, Max compressed load in Lymans book.

I also measured some unfired Win cases all where right at 2.08, OAL was 2.511 with a 250gr cast FN.

riverjackel The reamers I'm talking about chnge the leade angle to the lands for diffrent style bullets, I don't know enuff about it to really explain it I would like to learn more and fix this chamber problem. Seems like you could get a throating reamer that indexes off the rim and clean them up by hand ought to be easier than chambering for .357 max.

Ah jus dern't no nuff yeet. :shock:

JPH45 · « **Reply #11 on:** April 25, 2005, 03:34:02 PM »

I don't think a leade reamer would have enough diametr to be af any use. That diameter is detirmined by the bullet diameter not the case diameter. We need to talk with a reamer maker, someone wh knows what is going on and how to address it. Would be useless to ruin a working rifle, but it begins to sound more and more like we need a 375 Winchester reamer, nothing more.

When using the sizing die on finished rounds, it would be good to keep the amount of sizing to the minimum needed for the case to enter the chamber.