Hello All,

I have been learning by reading for several months, but am finally able to say I can't find this subject looking into the search mode. I have 2 30-30's I have been making Lyman's 311041 for. One a Marlin 336SS and the other a newer 336CB. Accuracy has been great. I sized the bullets to .311 and found both had groove diameters of .3085. I figured that 2 thousands over was about best for my accuracy. My problem happens more often on the newer 336CB. I have troubles chambering occasional rounds completely. I use RCBS X-dies for sizing, and use the Lyman M-die for expanding. Lee crimp die to finish things. My guess is that since the other dies work great for non-cast loads that either my .311 is too big,(why would it not be more consistant), or that the M-die is somehow damaging the case and giving an inconsistant expansion and changing the normal contour of the case. Any other ideas? I am already considering another expander. Any help would be appreciated.

I had the same trouble with that mould and my 1894 Winchester. The bullet was a bit wide to chamber nicely. I moved to a Lee .309" bullet mould and have not had trouble since. The bullet shoots very well too.

I suspect the inconsistency is caused by slight variation in the thickness of your brass. Measure outside neck diameter to check. I would take a caliper to the range and measure rounds that chambered hard, and compare to ones that chamber easily.

There are other possibilities, but this one seems most likely.

I use a Lyman M-die and .310" sizer with good results at the loading bench and the range with my 1953 M94 Winchester carbine. However, all the M-die does is bell the mouth slightly because I'm neck sizing with a Lee Collet Sizer down to about .308" OD. I have often wondered if I should try a .311" sizer but sticking with the .310" die for the time being simplifies things somewhat; i.e., I don't want to introduce another variable at this point in my 30-30 development. Oh yeah, I'm using brass with the Winchester headstamp. Neck thickness varies but averages out to approximately .010". I'm considering the purchase of a batch of .375 Winchester brass and turning the necks on a Forester Trimmer for greater uniformity.

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Well, I went out and experimented a little. I got engraving on the bullet itself and tried out shortening OAL. I got pretty good chambering with the slightly shortened OAL. I am loading a lower pressure powder, so pressures should not be too great. I am also going to try out sizing a thousanth smaller next time. Barrel likes the .311 size, but the leade does not. Would this be an excuse to fire lap the thing? I just started shooting this thing.

Dr. A,
This is an interesting discussion. I do not think that .311" is too large for your throat. I have used the Lyman 311291 as cast for many years in the .30-30, both Marlin and Winchester. The nose is large enough that it is engraved by the lands when chambered. There is slight resistance when chambering.
Even a Lee factory crimp die will sometimes bulge the case when a heavy crimp is applied. I would look there first. Take a round that will not chamber or one that chambers with resistance and try the following. Pull the neck expanding plug from your sizing die and run the loaded cartridge up into it just far enough to meet resistance. This will iron the crimp area. Then see if the round will chamber. You can sometimes bulge the case neck ever so slightly behind the crimp on the case mouth and not notice it.
The RCBS X-Die is supposed to "eliminate" case trimming but that has not been our experience with one we tried for the .260 Remington. You might pick up a Lee case trimmer and on your next batch of fired brass run all of them through the trimmer. Take a look at the case mouth and see if the cutter made a full circle on the case mouth. The .30-30 is one of those cases that crimps better with a uniform length.
I do not think that you will injure a case with the Lyman M-die. You can over flare the case mouth but the neck plug simply "conditions" the neck by opening it to a uniform diameter. Like the Lee Factory crimp die the M-die is one of those essential pieces of equipment for cast bullet shooting.
Use .375 brass for .30-30 loads with care. I have formed .30-30 Improved cases from .375 brass and shot them side by side with cases formed from both Winchester and Remington .30-30 brass. There is a significant difference is in indicated pressure, velocity and point of impact with .375 brass. We reduced our charges to achieve the same velocities. This was an interesting test.

Thanks for the response, William, I was hoping you would chime in. I was wondering if I could do what you are talking about. This is actually the first thing I was suspicious of. I might even try a good old roll crimp instead of the Lee factory crimp just to compare. This problem is present in my other 30-30, but not near to this extent. Without seeing the throat I am in the dark, but i am suspicious that there is no leade in this gun. The rifleing simply starts abruptly. This is not like the microgroove in my other gun. Good shooting.

Dr. A,
Get some cerrocast and make a casting of the throat, or if you are cheap, like me:-).Take a fired case, cut a wood or brass dowel to a length to fit from the base into the neck of case(you're making a bullet stop here). Use a soft lead slug and put it in the case mouth where it should stop against the dowel. Chamber it in the rifle and use a brass rod down the muzzle to hammer the slug into the dementions of your throat. I put a couple wraps of tape on the rod to protect the barrel.-JDL

JDL has the right idea. I have made Cerrosafe casts of both Winchester and Marlin chambers. The Winchesters allmost exactly match the chamber drawings in the NRA reloading handbook. The Marlins are slightly different. Niether one has much throat.
A Beartooth contributor, C. E. Harris, wrote what is probably the baseline articale on fitting cast bullets to micro groove barrels for the American Rifleman. Few people have shared more information on fitting cast bullets to production rifles than Mr. harris. Mr. Norm Johnson is a close second. Here is a link to an intersting articale he wrote on the subject.

http://www.schuetzen.net/marlin.htm

This forum sure needs a spell checker for those of us challenged in this area!

If you are using IE, try this for a free spell checker that works on this forum.

http://www.iespell.com/

Been using it for a while myself. :D

Dr.A ;You've recieved a lot of good responses here. I would like to make an observation. The RCBS-Xdie is a good idea. I've purchased one in 30WCF for my own use. It strikes me that it is untested in many respects. The brass, under pressure at fireing, WILL move. The die arrests its forward movement. I'd be looking at the brass thickness at the case mouths for part of the answer. Have you tried using an ordinary FL sizeing die? Pepe Ray

I think Pepe Ray is headed in the right direction with your difficulties. While true the RCBS X-Die is supposed to arrest case length growth, I suspect that through its use, you are actually, while not growing your cases in length, that brass that flows forward (yes, even with low pressure loads in bottleneck cases), is accumulating in the form of growing thickness in the case neck. If you have a good ball micrometer, it might be really revealing to measure the neck thickness of your brass, especially after a couple of firings and loadings using your X-die. I suspect that you'll find significant increases in the thickness of the brass in the necks of your fired/sized cases. I really doubt that when using 311041 that you'll have a problem with chambering .311" bullets caused by the bullet, but rather from varying brass thickness in the neck when using your X-die.

Please let us know what you find.

God Bless,

Yee-Ha,
I was able to successfully load up 30 rounds last night with the good old roll crimp from the x-die paired set. Had not used this since I long ago adopted the Lee Factory Crimp. I certainly have continued to trim my cases and maintain them. The crimp worked like a charm, and the chambering is not a problem. This is a tight chamber with the .311 sized Lymans, and gives great accuracy. I know that my other microgroove Marlin does not have this tightness. It is still extremely accurate. I shoot these at about 1980fps with a load of Winchester 748. Would it hurt to push it a little faster, or am I reaching a point of diminishing returns for this bullet.

C1RNR, Thanks! Learn somthing new every day!

Dr. A. You should be able to load cast bullets (150 and 170 grain) in the .30-30 to any speed that you shoot jacketed bullets. One if the joys of the old girl!