.223 primer depth question

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I did some testing and based off my testing, primer pocket reaming/ uniforming is very insignificant to the level of accuracy I require.
Ditto this. I have been reloading a long time and while I will concentrate on things such as bullet seating depth, crimping, trim length, flaring etc. I have never given much thought to primer seating depth and have always just seated them to the bottom of the pocket. I have on one occasion loaded LPP in LR cases with no problems even though they appeared to be a bit lower in the pocket than LRP would have been.

The only problem I ever encountered was with S & B .357 mag brass which had very tight pockets and wouldn't allow for complete seating of the primers and some stayed a little 'high' but I have since eliminated all S & B brass from my stocks.

While I can appreciate the OPs question my answer would be to not concern himself with it much, ensure his primers are seated correctly and 'bottomed out' and all other reloading variables are correct.
 
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Mikej

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While I can appreciate the OPs question my answer would be to not concern himself with it much, ensure his primers are seated correctly and 'bottomed out' and all other reloading variables are correct.
^^^^
 
Calipers, use the end...there's a depth rod that will protrude.
I use a depth mic myself. If I feel the need to do so. But after loading more than a few thousand rounds over these last 45 years an eye and a finger nail are easier. And actually you kind of have to work pretty hard at it to seat deeper than .003 of an inch.
 

Certaindeaf

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I've never had a problem with primers being seated too deep to include being absolutely crushed flat.
I have had problems with primers being not seated deep enough. Actions won't close, revolvers don't revolve.
Therefore I make damn sure they bottom out firmly and don't wobble on a flat surface.
 
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I use a depth mic myself. If I feel the need to do so. But after loading more than a few thousand rounds over these last 45 years an eye and a finger nail are easier. And actually you kind of have to work pretty hard at it to seat deeper than .003 of an inch.
These don't have to work very hard at seating a primer at any depth.

20210922_180936.jpg
 

fstdraw

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I've loaded thousands of .223 myself and have not had problems associated with primer depth ( Berdan primed is a different animal however). I just wanted opinions as to the optimum depth. I have to agree with Certaindeaf, deeper is better than too shallow. I pay special to the primer pockets now. Uniforming as best I can, cleaning well, running probe thru flash hole and removing crimp where needed. Hopefully all these steps always give me 100% reliability 100% of the time. Thanks to all.
 
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Another issue not mentioned is that of primer pocket cleanliness.

A lot of us have reloaded for a long time and not gave this much thought yet a clean primer pocket is essential for proper seating & depth and this is where liquid pin tumbling really helps as leaves the primer pockets looking like new.
 
I'm familiar with that end of the calipers, but was hoping for a specific tool. Thanks.
There are several company's that make a specific depth micrometer for measuring primer seating depth, however any depth micrometer will suffice and is a tad more accurate and reliable than using a set of digital calipers. Those who use those tools for a living don't trust calipers within a few thousandths.
For cleaning primer pockets I use an RCBS primer pocket brush mounted on a small electric motor. Yes it is an extra step but when they come out of the vibrating tumbler they are clean. And once upon a time I didn't pay much attention to cleaning the primer pockets, but that carbon can build up thick enough to prevent the primer from seating flush. Thus I made my primer pocket cleaner.

 

Mikej

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Another issue not mentioned is that of primer pocket cleanliness.

A lot of us have reloaded for a long time and not gave this much thought yet a clean primer pocket is essential for proper seating & depth and this is where liquid pin tumbling really helps as leaves the primer pockets looking like new.

but that carbon can build up thick enough to prevent the primer from seating flush. Thus I made my primer pocket cleaner.
To ad some context maybe...Been loading a bunch of handgun rounds since 2011. I don't mess with cleaning the primer pockets. Going to the comment of carbon build up in the primer pocket.....When it comes to seating primers in cleaned,(walnut tumbled with polish) cases, tap the case on the bench before seating a primer and again after seating a primer. A surprising, to me anyway, amount of carbon has been broken loose by the primer seating. Bottom line, I take the time to clean primer pockets on rifle rounds.

I don't measure primer depth on handgun rounds. I just seat until it is fully bottomed out.
 
To ad some context maybe...Been loading a bunch of handgun rounds since 2011. I don't mess with cleaning the primer pockets. Going to the comment of carbon build up in the primer pocket.....When it comes to seating primers in cleaned,(walnut tumbled with polish) cases, tap the case on the bench before seating a primer and again after seating a primer. A surprising, to me anyway, amount of carbon has been broken loose by the primer seating. Bottom line, I take the time to clean primer pockets on rifle rounds.

I don't measure primer depth on handgun rounds. I just seat until it is fully bottomed out.
That's your choice. I started cleaning primer pockets over 30 years ago when I had issues with the primer seating flush loading .45acp that had been loaded numerous times. Tumbling in corn cob or walnut does not always remove all the carbon so I now brush them before tumbling. We all have our opinions, generally obtained from personal experience. I've been reloading since 1976, have loaded for better than 30 different calibers, and re-load to my experience and knowledge. I'll not tell another what they must do, I tell them what has worked for me.

 
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