Straight Wall Cartridges

[oneokie]

The people on this forum have been very helpful to me in my quest for information on things to try in working up an accurate load for my 1894 Winchester in 38-55.[smilie=b:

Is the 38-55 cartridge by its self in suffering from large groove, small chamber problems? From what I have learned reading on the various forums and talking to people who have or have had rifles in this chambering, all seem to suffer from 38-55 itis. And it is not limited to one particular make of rifle.

Is this type problem common with all of the straight wall-straight taper cartirdges?

Do the various 45 caliber cartridges also suffer similiar?

What about the 405 Win?

What about the 50 caliber cartridges?

[ktw]

From what I have learned reading on the various forums and talking to people who have or have had rifles in this chambering, all seem to suffer from 38-55 itis. And it is not limited to one particular make of rifle.

Is it because the chambers are cut undersized or because a lot of the brass we use in these today has thicker necks than 38-55 brass used to have?

I also have a new 38-55 with a large (.382) groove diameter barrel. I blew out some 30-30 brass and ended up with neck walls that measured .0090" to .0105" thick depending on the headstamp. This makes a cartridge loaded with a groove diameter bullet a tight fit in the chamber.

I bought some new Starline brass and the neck walls on those all measure .0080" thick. Using the Starline brass it is easy to chamber a cartridge loaded with a bullet sized to groove diameter.

-ktw

[mazo kid]

Starline is now making the CORRECT length 38-55 brass for the "older" guns that require longer brass. Maybe this is what your rifle needs to be more accurate? Emery

[JohnH]

Unfortunately there is not a hard fast answer to your question concerning other chamberings and calibers. Trapdoor Springfields are quite commonly found with .460 groove diameters but dimensionally corret by SAMMI standards chambers. I doubt you'd find that large a groove diameter on any 45-70 manufactured after WWII. 45 Colt cylinders ofen had throats of 451-452 with groove diameter barrels of 454. Again, it was not untill after WWII that 452 became the norm for the groove diameter in the 45 Colt. this mismatch of cylinder throat and groove diameters actually gave the old Colt a reputation for not being highly accurate.

Time and space doesn't allow for a complete discussion of this overall topic, some have studied it a lifetime and will quickly state they don't know everything. Get your hands on and read everything you can by Ken Waters, Mike Venturino, Dave Scovill (I'm sure there are others) Ain't always quick answers either, and some answers are nest to bizzare. It was common practice in the 1800's to minorly alter something, put your name on it and market it. I could load a 250 grain bullet in a 45-70 case, call it the JohnH 45 Express, build a rifle around it and it would be considered proprietary.

The moniker "30-30" came into being because while both Remington and Marlin began to market rifles chambered in 30 WCF (Winchesters name for the cartridge) neither wanted to use the name "Winchester" on their guns and so used "30-30" instead. To bring this back to topic, many older '94 Wincheters in 30 WCF have 310 groove diameters, not 308. Are those barrels faulty machining, loose tolerances, poor quality control or different ideas of sizing and tolerances based on older thinking and experience with different materials and components than we use today.

[oneokie]

ktw wrote;


Is it because the chambers are cut undersized or because a lot of the brass we use in these today has thicker necks than 38-55 brass used to have?

MHO is that it is thicker brass and larger groove diameters. The old Winchesters had a groove of .3795". The new made guns regardless of Mfg. have grooves of .381" or larger. Dug out my stash of old (1963) brass, wall thickness is .008".

Sometime in the recent past, SAAMI changed the specs. on the 38-55 cartridge dimensions. Called SAAMI in 2004 and they had no explanation as to why, or when the dimensions were changed.

As to other specific calibers, the one that I hear of that has the most severe "itis" is the 405 Win.. People that I have talked to that have this chambering say that their groove dia. runs .318" Which is quite a bit larger than the old specs..

[TAWILDCATT]

check your measurement.is that .318 or .418.

[oneokie]

Oops! Dang fat fingers.

Should be .418".

[leftiye]

Starline Brass has the 38-55 long brass in stock. It's IIRC 2.125 " long. If'n yer case necks are too thick, how about turning them down?