I do have one and it does hold zero perfectly. As for fitting, sure it does; the norinco receiver is close to original tolerances than SAI's M1A. If you aren't convinced, Sadlak makes an inspection kit (included with the mounts anyway) if your receiver is offspec (not likely) Mike Sadlak can hook you up with a modded one.
Hi Charles
Thank you for your past business and continued interest in our products.
Yes I think the aluminum will hold up fine. The alloy is an aircraft quality heat-treated 6061. So if they use it on aircraft parts then the cold shouldn't effect it.
It certainly won't crack although the expansion of alum for the mount and scope vs the steel receiver might have a little effect but you would have to determine that.
My best guess at a reasonable temp range would be about 40 degrees F with regards to minimum expansion effects
Best Regards,
Mike Sadlak
Hi Charles,
At those cold temperatures [±5 F] I'm thinking that you might want to go all steel - steel mount and steel rings.
This way the expansion or in your case the contraction is the same for receiver, mount and rings. The Alum scope won't be effected as the contraction is more linear (length gets shorter).
The weight shouldn't be an issue as you said you are using it for load tests.
If I had to error on the side of caution I would pick the steel option.
Mike Sadlak