View Full Version : CDNN GI uppers

02-16-2006, 11:03 AM
The GI A1 uppers look like a good deal, but they dont come with bolt/carrier assemblies. What is the likelihood that my bolt/carrier from my A3 upper will work in it w/o problems? I've heard that you dont have headspace issues too bad with different bolts, unlike the M14 type rifles.

02-16-2006, 11:19 AM
Get a USGI Go/NoGo "Field" headspace gage to verify. All AR owners should have one.

Generally on ARs, new bolts on new or only moderately-used barrel (extension) aren't a problem. It's the old bolt on old barrel (extension) that's the problem child combo.

But you really don't want those USGI uppers - I'm presuming these were M16A1 uppers with triangular handguards and 'pencil' barrels. SARCO sells a similar setup.

These come with a 1 in 12" twist barrel which makes it really only suitable for lightweight bullets up to 55gr, max. If you want to shoot something heaver, it'll be very inaccurate. For example, 62gr M855 ammo is advised to be used in older M16A1s only for "combat emergency" - i.e., you have to put some lead out somewhere in desperation - as it's all over the target at 100yds.

02-16-2006, 11:33 AM
Perfect for the retro builds.:D

02-16-2006, 1:49 PM
Perfect for the retro builds.:D

That was my thought! I've been thinking about a retro build myself, since it's the config that I was issued and used in the 80's.


02-16-2006, 2:28 PM
Thanks for the replies fellas. :)