What's a good weapon after Gravelord +5 ?

Hi, I have my gravelord sword at +5 and it's pretty good but it won't touch the giants in the DLC wooded area.  

Decided to try making Quelaag's Furysword as I've ready good things about it, and I've done that; not reinforced it at all but in its native form it seems to be woefully underpowered compared to the gravelord (haven't tried it on the giants yet though).  Anyway, unless it scales significantly I won't bother wasting any more resources on it.

So what is better than a Gravelord+5 that will be good for those giants and possibly take me comfortably throughout the DLC and maybe also into ng+ ?

When you were using the Furysword, were you ensuring that you had 10 Humanity? But, if you like the curved greatswords, you can always try the Murakumo. If you don't have a good DEX stat, you should get it to Chaos+5.

Of course, which weapons will be effective for you will be based on your stats and your preferences.

EDIT: Sorry, missed the part about the giants.

Many of the Greatswords will slightly out-damage the Gravelord Sword. Assuming you have the Strength, the Ultra Greatswords and Ultra Greataxes will have significantly higher damage than the Gravelord Sword. Essentially, if you have high strength, you won't have an issue.

Thanks guys, I'll check out a +15 or the greatswords which I assume you can take up levels >+5.  Not sure what I have the strength for, I'm about 38 or so.

Zweihander and Black Knight Sword are pretty good, i finished my first playthrough, ever, with a GLS+5, and those are what i switched to when it stopped being effective, BKS for mobs and Zweihander for fewer, slower, stronger enemies, and bosses, it has insane poise break, and weighs 10 units, you could drop dem giants in 3 or 4 hits if you use buffs.
The giants are kinds OP though, it's not a big surprise they don't die, especially with a slashing wepaon.

I'm betting that with 38 Strength, you would probably have no problem with them if you use any of the Greataxes two-handed.

What are you're stats? Assuming you have the minimum stats to use the gravelord sword, if I were you I would get 27 strength and 2-hand a +15 Demon Great Machete. You'll be rocking 636 pure physical damage with hardly any stat investment. If you have a lot of slabs to throw around, you could even make a bunch of +5 crystal DGMs for a whopping 690 pure physical ar. Not bad eh?

What I'm noticing is that a lot of players are much faster with their sword, much faster moveset than my gravelord +5 or Man Serpent +15.  So I think I need to focus on speed a bit more.

But you're using a Strength build. If you want faster weapons, you'll either need to boost your Dex and suffer the curse of wasted stat points, or create a new Dex-oriented character. Have faith in your Strength; heavy, slow weapons have their merits.

With a +5 Dragon Tooth I could kill them in 2 attacks on my Havel Cosplay.

Dragon Tooth+5 with Gold Pine Resin. Tank the hits, hit back.