Hi Everyone
I'm trying to find the best option for 350 legend upper for an AR. I have a Sig SRD 45 and the 762 QD. I can't find any information if the 45 can will handle the 350 legend cartridge. Also can't find a sig adapter to fit the barrel for the 45 suppressor. Most of the uppers come with the 5/8 x 24. I can get the QD mount for the 762 suppressor. Will that work for 350 legend? Would I be at risk for a baffle strike since that's a pretty big difference from a 350 to a 30 cal. Thanks for your help.

Not saying go for it, but the hole in the end cap of the SRD762QD is .375", give or take .001".

The muzzle brake QD mount has an aperture of .35", give or take .001", so that won't work out well. Flash hider QD mount obviously has a bigger opening.

I obviously can't get into the baffle stack, but it would appear the entire bore of the silencer is about .375". That said, doesn't give you much clearance at all vs. a .30 bullet.

350 Legend operates at lower pressure than .308.

Those are just the numbers. I'd let SIG tell you for sure.

The only sites that reference the 350 Legend that I am aware of is Rugged Obsidian 45 and Liberty Mystic X. Barrel length is a determining factor.
Stainless steel (17-4) will handle the 350 legend.

Titanium should be able to handle the 350 legend, NOT sustained rapid fire or auto.

A direct fixed barrel mount would be best for the 350 Legend for either can. Identify the thread pitch of the Sig SRD and the 7.62. Talk to Nick at Ecco machine and ask his opinion. Nick can make you a fixed barrel mount.

Thanks so much for the replies. I'll do some more research on it and see what I can come up with.

the YHM R9 says it can do 350 Legend on a 16" barrel.

Take a look at Rex Silentium Suppressors. They offer a wide range of suppressors for different calibers. One model you choose the caliber, number of baffles, and type of mount.
The 350 Legend was designed to have about the same performance as the 30-30. You could get a .350 caliber suppressor with 4-6 baffles and you would end up with a fairly short & light weight setup.
YMMV...