I just bought one and a half (bbl/receiver) Garands from the CMP and I noticed the peepsight on my complete gun is loose.  It's a postwar sight.  My lockbar sight on my other receiver is perfectly stiff, I like the way it feels better than my postwar sight.  It's easier to turn the knobs and everything, and it's not loose.

Maybe we can fix that?  Here you'll see my sight is loose side to side, up and down and the site block is loose.  I'm confused, anyone know what might cause this?

I'm sure it's something simple, like tightening the tensioner screws or something, but I'm affraid to do anything without advice.  I dropped $400 on this thing, it's 60 years old and I'll risk asking a stupid question over possibly screwing something up.

Should my postwar sights feel worse than my lockbar sights on the other Garand I bought?

You have worn sight parts.
One common reason for loose apertures is a worn sight cover.  That's the wide steel cover that fits over the receiver sight area.
This is actually a spring that tensions the sight aperture.  If it's worn, the aperture will be loose.

Also, the rear sight base can be worn and the aperture itself can be worn allowing side to side movement.  The rear sight base is the block the aperture slides down into.

SOME movement is normal on a GI rifle.  Match grade rifles have all looseness in the sights tightened up by fitting and lapping the components.

Bottom line, you have worn sight parts, which is normal on most CMP rifles.
The "fix" is to either replace the sight components with new GI (not used) parts, in which there will still be at least some looseness, OR have the sight Match conditioned by an experienced builder.

FIRST, I'd talk to the CMP.  It's very possible they will send you better components to replace yours with.

Quoted: You have worn sight parts. One common reason for loose apertures is a worn sight cover.  That's the wide steel cover that fits over the receiver sight area. This is actually a spring that tensions the sight aperture.  If it's worn, the aperture will be loose. Also, the rear sight base can be worn and the aperture itself can be worn allowing side to side movement.  The rear sight base is the block the aperture slides down into. SOME movement is normal on a GI rifle.  Match grade rifles have all looseness in the sights tightened up by fitting and lapping the components. Bottom line, you have worn sight parts, which is normal on most CMP rifles. The "fix" is to either replace the sight components with new GI (not used) parts, in which there will still be at least some looseness, OR have the sight Match conditioned by an experienced builder. FIRST, I'd talk to the CMP.  It's very possible they will send you better components to replace yours with.

My field grade had the same situation with the rear sight.  I sent an email to the CMP, received a reply with a number to call, and spoke with an armorer about it.  After discussing the symptoms, he offered to exchange the rear sight cover at no charge, along with the gas cylinder lock that had worn threads on it.  Outstanding support for a rifle with no warranty.

Holy crap!  I can't believe they'll likely replace something that was screwed up on a gun I picked out myself (being too dumb to know what to look for).  I'll have to contact them tomorrow.

I'm just supprised the sight could be this loose from wear.  I figured I just had to tighten something.  Shid... well, maybe I can figure out how to temporarily put the lockbar sights from my other Garand receiver onto my complete rifle, so I can go shooting this weekend.

Quoted: Holy crap!  I can't believe they'll likely replace something that was screwed up on a gun I picked out myself (being too dumb to know what to look for).  I'll have to contact them tomorrow. I'm just supprised the sight could be this loose from wear.  I figured I just had to tighten something.  Shid... well, maybe I can figure out how to temporarily put the lockbar sights from my other Garand receiver onto my complete rifle, so I can go shooting this weekend.

If you IM me, I'll give you the name of the armorer at the south store that I spoke with last week.   I was very surprised at how helpful and willing he was to make everything right for me.  The only reason I sent an email at all was because two members on this board insisted that the CMP would take care of the problem.  I'm glad they convinced me to email the CMP and I encourage you to do the same.  Good luck!