Verify compatibility in the live workbench
Update 0.4.0.78 says the SCAR-H and M110A1 now share a muzzle-device slot and that a suppressor can be fitted to the SCAR-H. Compatibility and handling remain live values.
Practical use
Open the current weapon customization screen before buying parts. Test a new configuration in a low-risk context and carry enough ammunition for the role you actually plan to play.
Version note
This independently written guide summarizes current official update information. Check the live game client and official notes before making a high-risk decision, because live-service rules can change.
Independent guide based on supplied research and current official information.