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Primer seating depth and primer seating force

Personally I can’t tell ES from BS but I will be doing some side by side primer depth testing over the shooting season using as much precision as I can muster. If I can improve my groups I’m interested in finding out.
 
You post with no name, no specifics, offering pure conjecture. I'm not on a wagon, I'm not against if it works or good testing. I don't know if it has an effect. Pretty sure at short range it doesn't. What you count on is my calling three shot tests as not totally conclusive, and three shot SDs as evidence of statistical ignorance.
It wasn't directed at you. The old posts about this very topic have several very top names mentioning this and what tool they use to seat primers. And they shoot LR bench rest and shoot small consistently and hold records and test a lot. So I tend to listen to those names who can provide the Aggs and records and testing to back it. My comment was not at you but to everyone that says it doesn't matter
 
It wasn't directed at you. The old posts about this very topic have several very top names mentioning this and what tool they use to seat primers. And they shoot LR bench rest and shoot small consistently and hold records and test a lot. So I tend to listen to those names who can provide the Aggs and records and testing to back it. My comment was not at you but to everyone that says it doesn't matter
Clarification noted and appreciated. Do you have a link to that thread? I would like to read it. I am always interested in well sourced information.
 
Clarification noted and appreciated. Do you have a link to that thread? I would like to read it. I am always interested in well sourced information.
Let me look tonight. IIRC there are several posts about this. A few use the KM tool that lets you measure and seat each primer to each case. Lets you get same amount of crush on each case/primer you seat

 
This guy would make a great golf club salesman.

The golf guys are possibly the only people on the planet that are more anal than extreme accuracy shooters.

In my primary Disciplines, I feel safe in saying that the topic of this thread is a non issue. My game is about barrels, bullets, and tuning.

However, in the longer distances, especially those where bullet drop is influenced more and more by slight variations in velocity, little things like this could make a difference.
 
The older ones with the round primer tray are awesome, but I can probably prove their new ones with the folding tray and “safety feed” suck without breaking out my slide rule… And I still like Macallan 18... LOL
I had a loooooongtime relationship with the old round ones, but have been using the XR model for almost 5 years now. And, I have not broken a handle in all that time either! Most of the time with the round ones, I was up to my armpits with broken handles in the loading room.
 

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I make sure I baby my old ones. I keep them cleaned and lubed and don't let the kids borrow them any more either....

If you knew how many priming tools I have laying around, you would laugh... but life is too short to worry about such things. I was going to skip two bottles of Macallan 18 and get the CPS. Then I thought about it some more and got the CPS and two more bottles of Macallan 18 and read on here while I sip....
 
;) I may have had Macallan one time, back in late 1964?? Our A-Detachment had just arrived at a SF CIDG Camp in II CTZ, and we were undergoing (enduring) a Montagnard ceremony. Below are pics of me and the Detachment Commander drinking spirits...outa the jugs also pictured. I asked the old shaman what it was? I believe his reply was "Macallan"? But it tasted like fermented rice wine to me. :):D:confused:
 

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;) I may have had Macallan one time, back in late 1964?? Our A-Detachment had just arrived at a SF CIDG Camp in II CTZ, and we were undergoing (enduring) a Montagnard ceremony. Below are pics of me and the Detachment Commander drinking spirits...outa the jugs also pictured. I asked the old shaman what it was? I believe his reply was "Macallan"? But it tasted like fermented rice wine to me. :):D:confused:
So can we count on you to bring me some blue label to the next F class match? The only time I drink it is when someone else is buying. Otherwise I drink Black
 
I’ve been using an old RCBS priming tool for three decades, RCBS sends me new priming rods when I wear them out, no charge. It has great feel and has worked great for me. Maybe someday I’ll upgrade but for now I’ll just keep using the old one.
 

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If "feel" is important in primer seating, and not just placing the primer flush with the bottom of the primer pocket, then wouldn’t it make sense to measure the primer seating force?

If one would fabricate a “holder” similar to a case gage, then use a normal shell holder, drop the case to be primed with the shell holder in that “holder”, one could use a modified AMP press ram with an adjustable priming rod (with different lengths or otherwise adjustable), and use the AMP press to measure those seating forces.

Would that be feasible?

Thank You,
Tiago
This subject has been covered at least 5000 times. Guys at the Super Shoot that I watched use a simple hand tool. They try to shoot 25 shot aggregates under 0.200". I guess none of them know what they are doing.
 
All of this discussion is very interesting to me. I'm always trying to learn more. Often I wonder that, where I am today in terms of skill, does my inconsistency in trigger pull, setting up on the rifle, etc. negate some of the benefits that all of these concepts might provide me if I was better skillwise. Then, I also wonder whether because the tech and equipment are getting so good, is what's going on is starting to get more and more like pinewood derby was when we were kids, where how the car is built is what really determines the winner and not the driving. Anyway, just chining in really more to toss out a thanks to all that take the time to test and share, because for some of us reading it does help us a lot to get better - maybe not national champion better - but better in our own way.
 
Let me look tonight. IIRC there are several posts about this. A few use the KM tool that lets you measure and seat each primer to each case. Lets you get same amount of crush on each case/primer you seat

I just purchased that K&M tool after watching the Cortina interview with Dykstra and the Keith Glasscock video on the subject. I also burned 75 rounds testing four levels of crush as measured by that KM tool at 600 yards with a 6mm BRA using Federal 205M primers, I tested -.001, -.002, -.003 and -.004 with 15 shots each and a 15 shot control group seated by feel with my chinesium Frankfort Arsenal hand tool. Chronograph results were obtained with a Lab Radar. Rifle is a 30 inch Krieger shot off bags on the ground with a neo if any of that matters (f class rifle).
PRIMERS
-0.001​
-0.002​
-0.003​
-0.004​
Control "feel"
Average
2911.333​
2908.6​
2917.533​
2915.8​
2917.846​
SD
4.515​
5.225578​
7.957107​
5.062279​
6.174964​
ES
16​
19​
35​
23​
24​
I didn't find these results to indicate a statistically significate trend and found no correlation to vertical performance on target. On to a short review of the tool:

It works for its stated purpose setting crush measured from the height a given primer and depth of pocket (indexed from top of rim to bottom of pocket) for a given case. And it is awful to use, very uncomfortable the handle is a twisted piece of steel that is too short to provide the user with good leverage and the body of the tool is far to narrow to grip comfortably. If you like pain and wasting a lot of time seating primers this is the tool for you. In my eyes I lit 150$ dollars on fire (180$ with the sweet plastic hinged K&M carrying case).

I will test if further at short range to see if there is any effect on accuracy, because I am a sucker for the sunk cost fallacy.
 

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