choice of handguns

ok, here goes an attempt to create a comprehensible thread...
I might be getting back into SK soon (typo at first had SL, never been there XD)
and I need to decide which handgun to use, short story, the long story is I already decided on a gun and want a different one as well as the original. the original being the raptor and the second needing to be a high, single shot damage, med- high knock back handgun. Are the tortodrone guns worth waiting for or should I go after the shadow Magnus? (forgot the name sorry)

Thanks for the advice, and i dont already have raptor but am going for it ASAP

Antigua guns are for lightly peppering the enemy and for dealing finisher damage, they shouldn't be the main damage dealer on any set really.
Magnus style guns are powerful but can be tricky to use without getting hit, they shots go in a straight line and you have to stop (for a moment) to shoot, that slight stop can get you in trouble.
Blasters are good all around and are easy and safe to use, not to strong but not weak either.
Pulsars are great at long range but can seriously annoy allies with it's knockback.
Tortofists are even trickier to use since the regular attack pulls you forward and the charge pushes you back, not to mention both can be hard to aim.
Alchemers are also good guns if you can master the charge shot and until you hit 5 stars they can be weak, still they are not disruptive to allies and keep you mobile.
Don't worry about the Mixmaster as you probably may never even see one.......
Autoguns are powerful too but suffer from you having to stop whenever you shoot, some have knockback on the charge others don't.
Catalyzers are weird but can be fun though probably shouldn't be your first gun.

Raptor seems nice, but I would've preferred Callahan for Pierce. Antigua's are nice for slow movers like lumbers, but terrible for foes that dodge like beasts (counter-productive, sadly). I have an Argent Peacemaker, and it works WONDERS on FSC (hence, why it's even better for lumbers), but the thing is that it pretty much NEEDS UV's to be good; it's hit or miss. VERY safe and reliable, but it's true synergy is with medium to heavy hitting swordmasters. This + Glacius + FSC = win. Oh, and the charge sucks I guess.
Blasters have decent knockback, since you're looking for that. On single shot guns, they actually aren't as strong as you would expect. You can cheese Winter Grave on a gremlin (close range) and stunlock them with normal shots. The charge's explosion was, personally, underwhelming in size, but Iron Slug/Callahan can (potentially, mind you,) move foes out of visual range. I don't recommend it on non-arena areas.
Autoguns are VERY powerful, and can be considered a one-shot gun in the sense that it's actually a shotgun. And the patch made it's charge that much viable for med-far range.
My HUGEST problem for my pure gunner is melee protection. Like, FRUSTRATING levels of "SHOO GO AWAY LUMBER NO SLIME STAHP MAGNUS Y U NO BIGUR EXPLOD", so you should hopefully be carrying a sword as well.

In case anyone has missed the point of this thread, here it is:
...needing...a high, single shot damage, med- high knock back handgun. Are the tortodrone guns worth waiting for or should I go after the shadow Magnus?
The thread is asking a fairly specific question, not a "tell me about all handguns" question (although posters can discuss whatever they want, of course).

I'm just gonna go for shadow tech alchemer line and probably the raptor

It has nothing to do with your original goals, but it's is a great gun, once you learn how to use the ricochets. Have fun.

My HUGEST problem for my pure gunner is melee protection. Like, FRUSTRATING levels of "SHOO GO AWAY LUMBER NO SLIME STAHP MAGNUS Y U NO BIGUR EXPLOD"
Jelly cubes are probably one of the most evil standard mobs for all classes at close range due to the absolute voraciousness of the speed and scope of their attacks, and their nearly entirely unpredictable midrange attack, but against lumbers, all you have to do is circle them. It's not like you're rooted to the one spot when attacking like swordsmen are.

Really? I find it much easier to fight jellehs with swords, because you can bait them by attacking twice, do a slight pause so they can initiate their attack and move, then use the third hit to push them out of damaging range. The guns force you to move about, resulting in them becoming a pure wall of jelleh. Also, as you said, their midrange attack is the cheapest. Since you move with a melee attack, you have a slightly higher chance to avoid them, but a little above 1/4th of guns stop you. WRH can easily rek lumbers, especially if AT is off so you glide through them. That's just me though, I always get hit by slimes because I'm too tempted to get that last hit quickly. ;w;

Really? I find it much easier to fight jellehs with swords, because you can bait them by attacking twice, do a slight pause so they can initiate their attack and move, then use the third hit to push them out of damaging range.
Are you talking about one slime at a time? Or 3-4 of them? One slime is relatively easy when you cheese their AI, but it still requires a level of timing and elegance that feels at times like a dance. Managing more than 2 slimes when they have different offsets to their attack cooldowns is quite difficult (for me at least) and it's made especially tricky due to their extremely fast attack cooldown, IIRC it's only about 2 seconds.
So your loadout already contains Raptor/Gilded Griffin. I'm not sure why --- I wouldn't use it --- but let's go with that.
Now you want a second gun that does high single-shot damage and medium-high knockback? I'm not sure why, but let's go with it.
Really magnus-style guns are the only ones that meet your criteria, and only on the charge attacks. Callahan conflicts with your Gilded Griffin, so get Iron Slug or Winter Grave. Winter Grave has the advantage of non-normal damage. However, the freeze sometimes prevents the target from riding the charge attack. I might go for Iron Slug, even against shadow-vulnerable enemies.