Using a Socket as a comparator tool

[chrisward3]

Havent been able to get ahold of a bullet comparator up here in Canada, and was looking for opinions on a homemade solution. It will be used for 308, and I have heard of some ppl using a 9mm 12-pt socket that give consistent readings.

has anyone used anything similar? and if not, what homemade remedies would you recommend?

Cheers

 

[KYpatriot]

You can use anything that will is circular that will index on the shoulder of the case if you are measuring shoulder bump, because you typically only care about the difference in the readings before sizing to after sizing.

For a bullet comparator, you are concerned with an absolute measurement because you are trying to locate the bullet with respect to the lands...so your comparator needs to be sized to the proper diameter of the bullet...ie .284 or .308. You could machine one yourself, or just order one online. You should be able to backorder one if they are out of stock...

 

[bcrich]

I use a deprimed 40 cal case.

 

[former naval person]

The .40 case is just about on the datum line. Turn it around a few time to get an average. Works well.

 

[KYpatriot]

They are talking about measuring the shoulder bump on the 308 with a 40 case. You will need a purpose built comparator for your bullets if you are trying to measure case head to the ogive. Sinclairs and Hornady make ones that work fine I have used both.

 

[former naval person]

KY is right. Sorry. I like my Sinclair. Just make multiple measurements and don't push too hard. I have heard of folks taking a BIG nut and drilling out one flat to match the ogive size you want, and using it to measure.