Hi all,
I'm new to the forums and appreciate all the info you guys pass along.I haven't reloaded for about 8 years,so I guess I'm somewhat of a newbie.I just purchased the 30 378 Weatherby used. The former owner never fired brass twice-said too much "blowback" on the neck of case. This is with 97grns IMR 7828 with a 180 grn Nosler Partition.Have any of you guys heard of this problem or (as I suspect) he may have not been properly resizing the necks.I have also read some in the forums about neck only resizing,and am interested if it will work, but currently only have FL dies.Am slowly getting together things I will need(altho you can NEVER have enuf stuff!)Only have factory(yikes!!)ammo so far, but just hate to throw those cases away.Every time ya pull the trigger ya just mumble 4 bucks,4 bucks, 4 bucks.....

I myself have just joined the ACCUATE RELOADING FORUM. I have been shooting the Weatherby Accumark 30-378 Weatherby for about 7 years. The blowback on the cases is caused buy lack of brass expansion or a low pressure load. Really does not hurt anything because at some point the case does expand enough to seal off. Just makes for a dirty chamber. The 30-378 can be neck sized as I am currently using a Redding neck die. The problem you will run into with case life is the expansion of primer pockets. Make now mistake, it is a very powerful ctg. It will just floor an elk. By the same token many times it just zips through a whitetail if it does not hit bone. For hunting loads I am loading 119.5gr of AA-8700 with Nosler Partitions. For reduced loads try 84.0gr of RL-22 with Swift Scirroco 180s. Gets it down to the level of a 300 WSM. Please work up to the AA-8700 load.

Purchased my 30-378 Accumark when Weatherby came out with them. I use this rifle for long range Whitetail hunting. Never ran into the problem described, I load them 3 times (new brass) and discard them. For my hunting loads a always use new brass and full length resize.

Two years ago, I started to play around with loads for the 30-378. We finally settled on 168 grain Barnes TSX, Retumbo Powder (worked up to 112 grain, started at 109 grains), Federal 215 Match Grade Primers, and Weathergby/Norma Brass. Produces a nominal 3500 fps with exceptional accuracy...works very well in three different Accumarks.

As you know, always work up your loads carefully...and good luck

the smoked cases are from too light of loads , you can neck size with your dies , just back off about half a turn or so , use a colored marker to see how much sizeing is going on , i have some of this brass on hand , dont use it as forms out poorly in my 475 and worse in my 500 so drop a line if your interested , might get rid of it if price is right (but not exorbitant ) putting a dime between shell holder and die is about right with full sizeing dies to just neck size , and no need to buy a neck only die , but the new ones from lee with a full length die , dead length seater , and a neck only collet die seem to help make brass last very long indeed , i use them in my 300 and 375 h&h's with great accuracy and long life of brass .

If you use a full length die to partially size that way, be sure to check the cases to see if they'll chamber readily before loading them. Often you get a bit of body sizing around the shoulder area as well as neck sizing, and this can push the shoulder forward enough to cause chambering problems. I really do like Lee's collet neck sizing dies.