350 Legend

[Unclenick]

I wonder. It appeared to me from your photo that the Starline web is thinnest, but Nathan reported it clearing up his problems with the thicker (in your sample) Winchester brass (post #29). My table is for .308 Win brass, which I mentioned because the table is an example of possible head hardness variation. The big names, like Winchester and Remington, are known to contract out brass at times, so there's no guarantee the hardness relationship for the 308 Win measurements I showed are representative in any other particular lot.

[mehavey]

UncleNick, I call this conundrum the Yul Brynner Problem.
Right up there with the UV Catastrophe before Max Planck
(and why, gentle readers, the Sun really is black)



.

[stagpanther]

There were two principal problems associated with the original roll-out of the legend that me heavy and I got deep in the weeds with. The first was the support to the head of the brass--much like the problems of 9mm brass being supported in a pistol--the top of the web would often be left unsupported outside the chamber. The second issue was that the original SAAMI specs "allowed" for a total headspace stacking of tolerances up to .01". PTG was the first to release headspace gauges that allowed for a max of .007" as I recall. My inherent beef with the 350 L is that it shares many of the same basic design characteristics of the 9mm Luger--but obviously runs at much higher pressures. I've split lots of 9mm cases easily at only about 3 to 4 K psi past it's max pressure rating.

[Nathan]

The second issue was that the original SAAMI specs "allowed" for a total headspace stacking of tolerances up to .01". PTG was the first to release headspace gauges that allowed for a max of .007" as I recall.

Can you explain? SAAMI doesn’t seem to show head thickness or any breechface to head requirement....

Go be fair, I’m not sure what the 1.350” and 0.200” dimensions are. Looks like a false shoulder of sorts.

[stagpanther]

Can you explain? SAAMI doesn’t seem to show head thickness or any breechface to head requirement....

I haven't looked lately, but the original chamber spec submitted to SAAMI IIRC had a total headspace from bolt breech face to case mouth of .01"--which allowed for some of the issues associated with the case head having inadequate support in some of the earlier cartridges and barrels. So, some of the original no-go gauges (of which I still have a set somewhere) could give you a "false positive" of the bolt not closing at .01" headspace. PTG's no-go would close at around .007"--meaning, essentially, they recognized early on the problems with the original "over spaced" headspace setting. I was tipped off to this by a well-known manufacturer of custom rifles who discovered the same problem early on. Just like with the initial roll-out of the 224 valkyrie (another magical mystery roller coaster ride I took), hardware was being sold to "unfinalized" specs. Then there was the issue of "cam-locking" the bullet to the case mouth with some cases that were too long and with a chamber with a steep step down in the throat just after the case mouth--again, my memory is fuzzy but I think meheavy ran into this (?).