I know this has been asked before I'm back and forth between the octane 9 and octane 45.  45 is about an inch longer and a couple ounces heavier.  I wouldn't mind the extra inch really but I'm not sure about the trade off in suppression for the capability to shoot 45...  I know 45 can has more volume but will it actually be as quiet as a octane 9?  I don't own a .45 any longer right now and not sure if I will in the future but you never know I guess. Also how do they both perform on .300 blk.  One other question is it possible to run 357 mag through these cans?

Thanks,
Thomas

I went with the 9HD, because, like you, I'm not sure I'll get a 45, and I've seen posts where SiCo has said 357 magnum is a go.  Mine will be used on a Sig 9MM and a SBR with a TROS 5" barrel using a 3-lug mount...

Check out testing done by Silencer Shop. The difference is minimal. Go with a .45 can.

The Army wants to change the sidearm and perhaps caliber. If .45's or .40's in the future are the new 9mm, you will be good to go.

I'm talking about years in the Future. May or may not happen, but suppressors are a life time purchase. Go with a .45 can :)

OP...do you already have another 45 can?  Here was some of my thought process.

I bought a 45Osprey as my first can, based on the ability to shoot multi-caliber. I don't own any .45s either, never have. The Osprey is one of the few lines that actually offers a .40 version, of which I have several. However, I opted for the .45 model just so I didn't regret it down the road.

When it came time for a second pistol can, and knowing I had my 9mm AR in the works, I opted for an Octane 9 HD 2. Lighter, shorter, and $100 less. But I have the Osprey for other stuff. With the AR, I can now even decide to shorten the barrel (currently 7") and the Octane will slip inside the rail a bit.

Bottom line is I think everyone should have a .45 can. The 230gr projectiles are simply too plentiful and easy to suppress to not buy a .45 host (whether handgun or PCC) at some point. It doesn't have to be the first can you buy, especially if you only have 9mm hosts.

I did the exact same thing as BigWaylon.  First got a 45 Osprey then an Octane 9HD for my 9mm AR and some rimfire stuff.  The Octane 45 would have worked for all of them but I'm very happy with both cans.

Here is a video that should help you (OP) decide.

Not my video.

http://m.youtube.com/watch?v=epK70OzQgKg

I am very happy with my Octane 45 on my 9mm AR and 300 blk SBR.  I cannot compare it to a 9mm can as mine (Evo9) is still pending, but I will once I get it.  I was pretty surprised by how quiet the Octane 45 is on my XDM 9mm, it definitely surpassed my expectations.  So if you think you might get a bigger caliber in the future, then get the 45 can now. 9mm cans are for people who already have a 45 can and/or are 100% certain that they will never go bigger.

Meh.... I went with an Octane 9 because it will be used 99.2% on my 9mm SBR.  I wanted it short and lighter so a 45 was not considered.

Octane 45 is very, very quiet using subsonic 9mm

No I don't have a 45 can as of now. It's just hard because I.can only see myself shooting the 9 and .300 blk. The only other option that would be cool is to thread a 357 lever gun.   Also would the 9 be a better can for a .22 host? Or is there not much difference between those with either can?  I'm sure I'll pick up a sparrow or outback someday just not yet

My Octane 9 is my backup-backup-backup 22 can. Two Spectre IIs and a Warlock II ahead of it in line for the same reasons discusses above...length and weight, but also diameter.

It works, but there are definitely better dedicated options out there.

Ended up purchasing the octane 9. 1 inch shorter and better performance with 9mm.  Now if silencerco made a 9mm endcap that performed better than the 9 like the saker 762 with 5.56 I may have chosen differently. In any case in the unforeseeable future if I do decide to pick up another 45 its an excuse to get another can in the pipeline