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Old 10-30-2009, 10:08 PM
drywash drywash is offline
 
Join Date: Oct 2009
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Default Comparator? rookie question!

Am looking for case gage or gage"s. What the heck is a "comparator". Saw in Midway Nov. Flyer (Hornady Headspace Gage 5 Bushing Set w/Comparator. Just looking for a good gage to set reloading sizer die 30-06 for M-1 ammo. reloading.
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  #2  
Old 10-31-2009, 01:46 AM
sunray sunray is offline
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Location: London, Ontario
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They're a way of separating you from your money. The best guage is the chamber of your rifle.
Been loading for my rifle for about 30 years. The only important thing is to full length resize your cases every time and watch the case lengths. FL resizing every time is required for any semi-auto.
You don't need a guage to set up your dies. Just set up the dies, all of 'em, so the shell holder just kisses the bottom of the die with the ram all the way up. Then adjust the seating die to give you the OAL you want. 3.340" works just fine with most bullet weights.
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Old 10-31-2009, 11:27 AM
Dave Stitz Dave Stitz is offline
 
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Location: Doylestown, PA.
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Quote:
Originally Posted by drywash View Post
Am looking for case gage or gage"s. What the heck is a "comparator". Saw in Midway Nov. Flyer (Hornady Headspace Gage 5 Bushing Set w/Comparator. Just looking for a good gage to set reloading sizer die 30-06 for M-1 ammo. reloading.
See the Post from Ceresco in the "Cartidge case gauge" thread. Very good info.

The " Comparator" does not have anything to with full length resizing. It is mainly used for seating the projectile to a required depth once you know how far off the lands you need to be for your rifles chamber. Some rifles with a lot of throat erosion will be a waste of time and effort, cause the lands will be so far from the bullet that the bullet seated just off the lands will not even be in the neck of the case.

The RCBS precision Mic gauge will tell you the exact headspace of your rifles chamber after measureing some of your fired brass cases. Then you use it to set your full length resizing die to the required push back of the shoulder of the brass without overworking your brass.

http://www.midwayusa.com/viewproduct...tnumber=622021

Dave
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Old 11-01-2009, 07:47 AM
mac1_131 mac1_131 is offline
 
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Posts: 105
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I would suggest the L E Wilson cartridge gauges. I use those to set my trim length with, which I think is what you are getting at. I have one for .223, .308 and 30-06 and set up my case trimmer and sizing dies using them.

The comparator is a totally different animal. It attaches to your micrometer and measures bullets on the oglive, instead of the overall length. This is useful when you want to set bullets into, or just short of the rifling. Mostly used in .223 for 80 grain loads that are single loaded and longer than magazine length, and have the opportunity to gain accuracy by being loaded to where they chamber into the rifling.

Not sure that can be done in an M1 or not, but definately can with an AR.

So anyway, look into the Wilson cartridge headspace gauges, I think that is what you are looking for.
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