That Defense EV should be 4, not 6. In all honesty, I wouldn't run Loaded Dice with Heracross because Bug / Rock and the lower accuracy can really hurt Heracross's chances of pulling off successful Volc baiting. I'd recommend Assault Vest with Trailblaze and alternate coverage instead -
Heracross @ Assault Vest
Ability: Moxie
Tera Type: Rock
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Earthquake
- Throat Chop
- Rock Slide
- Trailblaze
Earthquake, Throat Chop, Rock Slide with Trailblaze and Assault Vest + Moxie boost allows you to take a stray hit more effectively on the Special side, and because the set didn't rely on support coverage, to begin with, AV is a more safe bet if you're trying to differentiate Heracross. Rock Slide still works better than Rock Blast after Trailblaze because it doesn't require an item slot for consistent power, allowing you to allocate an item that suits Hera way better (Hera's Special Defense is naturally better than its Defense, so enhancing that provides Heracross additional switch-in opportunities. The reason I would use Loaded Dice on a niche pick like Klawf is because of additional factors that allowed me room to use that item (Klawf has Regenerator, for example)
I'll address these in points to keep things simpler.
1. I'm used to filling in all 510 points, so I put 6 instead of 4. Just a personal quirk.
2. In most cases, the "lower accuracy" is actually a better option than the alternative.
-Pin Missile vs Megahorn: 95% vs 85%
-Rock Blast vs Rock Slide vs Stone Miss: 90% vs 90% vs 80%
In terms of damage output, options are actually either on par or better.
-Rock Blast vs Rock Slide vs Stone Miss: 100 (4 hits) vs 75 vs 100
-Pin Missile vs Megahorn: 100 (4 hits) vs 120 (not factoring in STAB. At 5 hits, it's 125 vs 100.)
Pin Missile vs Megahorn and Throat Chop also doesn't make contact, so if Volc isn't Tera'd, Rock Blast kills it immediately with 0 chances of Flame Body activating. If they're somehow wise to the shenanigans, then Pin Missile kills it with 0 chances of Flame Body.
Another bonus for it is that mons with Focus Sash that are outsped after +1 Speed also die without them having a chance to fight back because of multi-hit moves. The major downside is that when Annihilape was around, it was a hard counter. Primeape is also a counter, as Rage Fist gets free stacks.
As for Loaded Dice vs another item, may I offer you Iron Thorns, Tyranitar, and Baxcalibur? All of them pretty much do the same thing Hera likes to, except they have better offensive setup through Swords Dance or Dragon Dance. They could use other items like Air Balloon, Scarf, Band, or Life Orb... But people who use sets like mine don't; they use dice instead. Especially Bax. While having an AV would be nicer for Hera, I just don't see it giving me as much opportunity to really push damage out.
I tried a variation of this set and lemme just say, if you need a complete side-man or death fodder to grant something else a free switch-in, few get the job done better than Loaded Dice Heracross.
I too was tempted by using Mega-Heracross at home which kept some of Heracross's perks like Guts and its better speed tier. However, this set has far too many flaws. Without a Guts boost, Heracross's initial power is way too shaky to reliably land KOes. It's speed isn't too good either and it has severe 4MSS since it wants all of Bullet Seed, SD, Rock Blast, CC, EQ, etc. It also wants multiple Tera Types since Grass lets it beat Dozo while Rock helps it w/ Dirge. While these types help Heracross out in the moment, the are easy to exploit since both have many common weaknesses. Without investment, it's Bulk isn't good enough to really switch into anything. It can't even switch into Pokemon like Iron Treads or Great Tusk since they just use Knock Off and make half its moves useless. Loaded Dice sucks for another reason, which is that a lot of the time, it will hit only 4 times, causing you to miss out on crucial KOes.
I think your set might be better than my set since you lean more in its sweeping capabilities, but ultimately, I think using Heracross with Loaded Dice is just too big of a gamble.
I actually find myself having very few, if any, of these issues I see you having. Guts vs Moxie is always an endless debate for Hera, as Moxie allows you to snowball, but Guts gives you immediate power at the cost of your HP each turn. I wanted more snowballing to apply pressure.
Hera DOES have 4MSS to a bad degree, I cannot deny that. I'd LIKE to have Bullet Seed on the set, but then I'd have Trailblaze AND Bullet Seed which is a bad overlap. Or I sacrifice the +1 speed setup to have Bullet Seed and EQ.
I'm full-in on Tera Rock, honestly. Bozo can be dealt with by other Pokemon, and Rock allows you to turn the tables on most Flying, Fire, and Bug types that want to come in to try and either nuke you, or wall you. Rock also takes away your 4x weakness to Flying without keeping you weak to it.