Question about 38-55 mould

[KirkD]

I am wondering if anyone uses the .376" 37-250 FNGC 250 Grn RCBS Bullet Mould. It says that it is a .376 mould, but I need at least .378 and preferably .379. If you have one, what is the pre-sized diameter using plain wheel weights with a bit of tin thrown in?

[KirkD]

I wonder if that could be increased a bit by adding some tin? Is that .377' diameter measured right away, or a few weeks later?

[Old Goat Keeper]

KirkD before you do anything slug your barrel ESPECIALLY if it is a . Those 38-55 barrels wander all over the place for bore size. And if you don't fit the slug to the bore properly you ain't gonna get any accursadcy from it.

T-o-m who has several 38-55s

[GabbyM]

kirkD:
Do you already have this RCBS mold or are you just looking at it?

Only way an RCBS mould will make full diameter is to use the Linotype they are regulated for. Which is BS to the nth degree. Get a mold from one of the job shops advertising here and don’t look back. If you‘ve an RCBS that does not make the diameter just play with it for a while until you can replace it.

You can Beagle it with tape up to the point where the gas check does not fit the shank. Best process is to just write RCBS and tell them what you think of there Scab headed operations.

[KirkD]

I have not ordered the mould yet. I wanted to find out a few things first. It may be that I'll have to order a custom mould.

[Bent Ramrod]

I looked at the RCBS but eventually went with the Accurate mould, which I specified to cast at .381" for a greatly oversized Highwall barrel. Fortunately the chamber was also pretty oversized so the loaded rounds chambered with no trouble.

The mould was everything I specified, excellent workmanship.

[Jon K]

The RCBS 37-250 is built for a .375 bore...NOT .379-380 bore.

Look elsewhere, don't wste your time & money trying to make it bigger than it will cast.

Jon

[w30wcf]

Kirk
The correct g.c. mold for the 38-55 by Ideal / Lyman was the 375296. A friend had that mold and it dropped bullets at .381" in w.w. Its been obsolete for awhile now.

As was suggested, your best option would be Accurate Molds.
His 38-270L looks very similar to the 375296.
http://www.accuratemolds.com/bullet_detail.php?bullet=38-270L-D.png

If you wanted a wider meplat you could ask Tom and he would do it for you....no extra charge.

Bullet diameter is specified by the customer at the time of ordering and Tom guarantees -.000 +.0015 on the diameter based on the alloy used (specified at the time an order is placed).

I now have 4 Accurate Molds and they are among the very best that I own.:mrgreen:

w30wcf

[JFE]

My RCBS mould drops bullets at 0.378 using a 14 BHN alloy.

[KirkD]

Wow! That 38-270L looks like exactly what I want. I actually want it for two cartridges, my 38-55 and my 38-72. The 38-55 standard weight is 255 grains and the 38-72 was designed for a 275 grain bullet. That 28-72 looks like a perfect compromise. I think I have found what I was looking for.

Question: What is your twist rate and how fast do you need to shoot that long bullet to keep it from wobbling?

[oneokie]

Most 38-55 twist rates are 1-18. Some are as fast as 1-12. What rifle and what distance?

[KirkD]

My 38-72 seems to have a 1:26 twist as near as I can measure, which was the earliest twist. I don't know what my 38-55 has, but it is a Model 1894 that was received in warehouse in 1899.

[oneokie]

I don't know what my 38-55 has, but it is a Model 1894 that was received in warehouse in 1899.

Most likely 1-18 twist with a .379" or larger bore. My bore is .3795" and I use the LEE 379-250 boolit.