Need help identifying mystery objects

[BigBubbaDaddy]

Hi guys,

Going through some odds and ends that were part of a load of items I picked up from a bench rest shooters estate.

I have two little items that have been driving me a bit nuts trying to figure out what they are.

First item is this little aluminum body that has three changeable collars. Each collar has markings: 6-27, 7-28 and the last one is 3-24.



The second item is actually a set, I have a couple little ziplock bags that all contain the same thing, these two aluminum points, and a series of o-rings.



Any help will be appreciated, I can't stand not being able to figure out the use of a thing, its like getting a bad song stuck in your head!

[foxtrotuniformlima]

The first item is a bullet comparator ; http://www.sinclairintl.com/reloadin...prod35659.aspx

[BigBubbaDaddy]

Thanks Foxtrot! They even had a video showing how to use it!

[dskit]

The second look like replacement O-rings and the tool to put them on for a Dewey cleaning rod.

http://www.midwayusa.com/Product/412990/dewey-replacement-o-ring-kit-3

[FLIGHT762]

Second photo is of two tools to replace the O rings on nylon bore guides. You slip the end of the insert into the end of the bore guide and slide the O rings over the tapered end and roll the O rings into the groove on the bore guide.

Tapered of the tool opens the O rings and makes replacing the O rings easy.

[BigBubbaDaddy]

Thanks dsikt and flight762... you guys rock. No more mind worms eating away at me.

[BigBubbaDaddy]

Okay...one more. No markings...

[highpower790]

Looks like a go/no go gauge.