Does the cannalure do anything to effect accuracy? I am looking into some bulk Hornadys FMJ for my r-15 (plinking) and all I see are cannalured. Do they effect accuracy if I do not crimp them?
For plinking I wouldn't worry about a cannelure but I would be concerned about FMJ's. They will ricochet all over creation so be very careful where you shoot them. I think you can get the MidSouth Varminters, Winchester's, Remington's or Hornady's 55 grain ptsp with a cannelure for about the same price or maybe even cheaper and they're much safer to shoot. I think I saw the MidSouth ones for about $35.00 for 500. If you're willing to buy a couple thousand you might find them cheaper than that.
I have never noticed a difference with or with out as far as accuracy. The cannelure does make it easy to crimp when using a powder that does best with a good solid crimp.
No, it won't make any difference at all. I just haven't noticed a lot of accuracy difference with cannalured bullets. At least not for hunting. I shoot them out of my .223, 22-250 and my .243 for varmints and shoot various bullets both with and without cannalure out of my 7mm08, .308 and .300 WSM for big game. I've never crimped any bottle necked rifle cartridges up to and including my .338 Win Mag.
I've shot a lot of the Speer 55 gr. cannalured SPs and had pretty good luck with them. I didn't see any difference from the non-cannalured, but the rifle I had then wasn't accurate enough to make an absolute statement about that.