I just saw some brass for the 35 Herrett that had been formed from .375 brass instead of 30-30 brass. What is the deal with this? I can understand that a much heavier web would have it's advantages, especially for full boat loads with heavy bullets. Is this as non-technical as substituting rimmed .375 brass for 30-30 and working through the process with the dies I already have? What are the particulars? There must be more to this that my ignorance is preventing me from seeing. OR I'm looking for monsters under the bed. Thanks in advance for your help. Jeff

Sounds to me like someone had some excess .375 brass for the forming. Rim diameter and thickness are the same - the 30-30 has .421" base dia. compared to the .375's .4198". That means you'll get some extra chamber enlargement at the base. The thicker web would restrict capacity somewhat.

Dunno' - don't see any reason you couldn't use the .375's if you had surplus supply of them, otherwise, think I'd just stick with the more plentiful 30-30 cases.

I just saw some brass for the 35 Herrett that had been formed from .375 brass instead of 30-30 brass. What is the deal with this? I can understand that a much heavier web would have it's advantages, especially for full boat loads with heavy bullets. Is this as non-technical as substituting rimmed .375 brass for 30-30 and working through the process with the dies I already have? What are the particulars? There must be more to this that my ignorance is preventing me from seeing. OR I'm looking for monsters under the bed. Thanks in advance for your help. Jeff

Some people think the .375brass is stronger. Can form some from 30-30's, and check the weight difference between .375 and 30-30 cases after forming. Assumption is that if one is heavier than the other, and they both have the same outside dimentions, the "extra" brass must be in the case walls. Does make the case volume a bit less, which will increase prssure for a given charge...but some folks feel the slight thickness increase is worth the effort of forming .375 cases.

Maybe the .375 brass was used because it fit the chamber better than the 30-30 brass.

I don't have any .375 brass to measure but my .38-55 brass mikes .4191-.4192.I miked a bunch of .30-30 and .32 WCF
brass and it measured from .4135-.4162.There were 4 different brands,it ranged in age from new -50 years old.

WC

I used thje 357 Herrett for IHMSA matches for several years. I only used .375 Winchester brass as it was designed a little heavier to handle more pressure (if I recall, they used the same basic case to load the .307 cartridge also). It is also more consistent than .30-30 brass. Pressures are slightly higher in the reduced volume case, but the Herrett doesn't need to be loaded max anyway. This concept was discussed at length in IHMSA literature of the time and quite in vogue. The Contender I used took many trophies, and was awesome on the rams at 200 meters. Just be prepared to spend some money on a shooting glove, band-aids for the web of your shooting hand and some steroid injections in the wrist. Ouch!

P.S. The .375 brass was also formed to a slightly short necked .30-30 case for the contender that headspaced on the shoulder for IHMSA matches. Same reasons - stronger brass, better accuracy. I also used it to form 7mm Rimmed IHSMA cartridges (a wildcat similar to the 7mm Waters) and it was the basis of Elgin Gates .375 Super Mag revolver cartridge.

axlenut

Thanks for the input. I'm still learning and do appreciate each of your time. I've run some pretty warm loads behind 180 gr. sp, and developed some very accurate loads for same without approaching excessive preasure so I will stick with 30/30 brass cause I got a good source for once-fired RP which has performed better than other brands since I first bought the barrel. Thanks again for your help. Jeff