The attraction to a �hotter� .30-30 isn�t the cartridge, it�s the rifle. The Winchester 94 / Marlin 336�s are just extremely handy rifles to tote in the field. I will agree that both rifles can handle 40,000cup in post WWII (and perhaps even earlier, but why abuse such classics) rifles. But regardless, you can expect some accelerated wear because of the tapered shape of the .30-30. A tapered cartridge*, all else being equal, will produce greater backward thrust than a non-tapered cartridge because the wedge shape pushes the cartridge rearward.
When my M1 Carbine broke its extractor (as in, completely gone), the little rifle still cycled 14 out of 15 rounds in the magazine because of its tapered shape and very clean chamber; really drove this lesson home.
I�m much more comfortable pushing the .30-30AI to the 40k pressure limit than I am the standard .30-30 for this reason. No, I�m not worried in the least about blowing a rifle up. But I do worry about unnecessary abuse to the action of a decent gun. The .30-30AI essentially removes all case taper and as such, the cartridge case clings tightly to the chamber walls, offering up almost no back thrust against the bolt face. I�ve read several times where someone had setup a test bed Winchester 94 (I think Ackley did this as well), with no locking block and discharged a .30-30AI, and nothing exciting happened at all. The rifle fired and everything held fast. I�ve never tried this myself, but I might just rig something to safely pull this off so I can see for myself.
*all depends on how steep is the taper
My favorite loads are all for the 150 grain bullet because I�ve never been able to see a difference in bullet performance between the 150 and 170, so why bother with the extra recoil.
Standard .30-30
31.5 grains IMR3031
33 grains AA2520
34 grains 748
.30-30AI
40 grains BL-C2
I can�t remember my 3031 load off the top of my head.
