I've noticed a lot of visits on this question in only a week. My answer if quite complete for this cartride, but I'm sure many readers want to make faster guns shoot lead accurately. Lapping the bore with the LBT lap kit, then using a properly fitted LBT bullet design, gas checked, with LBT lube, will take 30-06 class rifles to near the jacketed bullet velocity limit, and I've taken several magnum rifles within a couple hundred fps of full throttle. This with around 1 1/2 inch three shot groups at 100 yards, when the best jacketed loads would go around an inch from the same gun. -- If you have unaswered questions, feel free to ask.
I think so, because the 358 isn't a really high speed cartridge. On the other hand, it is a 60,000 psi gun which is at the pressure limit for cast in most guns, so if your loads are up there pressurewise, you just may be getting all you are going to get.
I design my bullets to provide a very strong bearing surface which keeps them centered and in balance when pounded with heavy loads, and also set the lubrication grooves and gas check shank up for maximum velocity, unless requested to cut something special, which quite a few customers ask for. I have shot LBT bullets from a 30-06 at speeds to 3200 fps with good hunting accuracy and no leading. At 2800 with the heavier weights normally used in the o6, only extreme pressure with fast powder causes problems. I've also obtained 2800 fps in 458 Win Mag with 400 gr bullet, and 2200 with 500 gr, which is way over jacketed velocity with those weights. This because pressures were lower with lead in that cartridge, and they should be in your 358. No leading and 1 inch groups at 100 yards. So unless you are running max pressure, and are sure the Felix lube is giving lower pressure then LBT lube, LBT will give you more speed, accurately, without fouling.
You're the first to tell me that any lube would match LBT lube, and if Felix lube does, good. It's about time another lube manufacture sells something besides wax for lubricant. -- However, that fact that Felix will match velicities with LBT lube is perhaps an indicator that your velocity limit is being established by the bullet design. i.e. It isn't strong enough to handle more speed/pressure, but if it were, one of the lubes would show accuracy and freedom from leading at a higher velocity than the other, and, or, one would hit maximum pressure for the gun with a lower powder charge. This when judging pressure by case extraction as one does with strong rifles and jacketed bullets. All lubes I have tested have reached maximum pressure with much lower charges than with LBT lube, sometimes with higher velicities with that charge than with LBT lube, but with a stron LBT bullet design, and more powder to get to maximum pressure, the LBT lubed bullets have always won by 200 to 500 fps higher velocity.
BY DESIGN!
