The Firing Line Forums - View Single Post - thread size of standard AR-15 barrel

ava8harrierusmc1 · December 26, 2009, 01:40 AM

Hello I have a problem I want to buy new upper for my M4 type AR-15 rifle and i need to know the standard thread size of the barrel so that i can when i order my muzzle break I get the correct size I do remember that i read somewhere that it was 1'2'' by 28 threads for the .223 cal. also is that the same size for 6.8 AR type rifle. Thank you for your assistance with this problem.

December 26, 2009, 01:40 AM	#1
ava8harrierusmc1 Member Join Date: May 18, 2009 Location: Rocklin CA Posts: 15	thread size of standard AR-15 barrel Hello I have a problem I want to buy new upper for my M4 type AR-15 rifle and i need to know the standard thread size of the barrel so that i can when i order my muzzle break I get the correct size I do remember that i read somewhere that it was 1'2'' by 28 threads for the .223 cal. also is that the same size for 6.8 AR type rifle. Thank you for your assistance with this problem. __________________ Life is just to short to be upset by the little things in life. So if something big happens and you don't like it just wait hopefully in the end they will get it in the end if you know what I mean!