Century Arms L1A1 Sporter. Inch or Metric???

[Tigerclaw_x]

Hi. I have the Century Arms L1A1 Sporter on Imbel Receiver. The one with a goofy looking thumbhole stock and no muzzle break on a barrel.
I need to know is it an entirely inch pattern gun, or is it an inch pattern gun built on metric receiver or is it a metric gun made to look like an inch pattern
L1A1. Thank you

 

[Onmilo]

The upper receiver is metric dimensioned with an inch dimension L1A1 barrel assembly crush fit into the metric receiver threads.
The bolts and carriers and the lower receiver are inch pattern and the cocking handle is an inch pattern modified to fit the metric dimension slot.

 

[CYANIDEGENOCIDE]

if you are asking for the purpose of finding correct magazines, check the front of the mag well. If the notch the magazine locks into looks like a crescent moon on its side its metric, if not then inch

 

[DougW]

The Century R1A1 I had a few years ago had an inch lower that would take both magazines. It also had the infamous "unibrow" feed ramp that worked better after I polished it. The rifle was very sound and worked great. Traded it for an M1D.