Primer pocket truing

Well for myself I would like to know the harm I am doing. I have the hand held/manual tools. I can see the problems that could happen. Am I enlarging the pocket depth or circumference? What damage to the flash hole. I am not a recreation shooter. I load a hundred or so rounds each season to hunt with and to verify data.
Not much if any. For years I uniformed pockets. Can you make a rifle shoot 1"s and 2"s at 1k with uniformed pockets? Yes. Many can attest to that. Some of my latest testing has me thinking they may shoot slightly smaller with the factory pocket. It may be the radius. Im talking less than an inch at 1k. Maybe less than a half inch. Its hard to say at that point. Its something that will take a few barrels to know for sure. But your ok either way.
 
I do debur the flash hole and do a quick pocket true on all my brass new or old. More to make sure I don't miss something than to do much other than a basic cleaning. It also provides consistency with my process. In the end, I find that consistency is what allows for the best ammunition output.
Howdy, what he said. Consistency and same routine everytime. Happy shooter. 😎
 
My thought on primer pocket truing etc with quality brass... Lapua. Is what is the ref point to indicate off of and how does that effect all other critical areas.

All the uniformers ref off the case base. What if the rim thickness varies?
What is the measurement for rim thickness?
Then what is the measurement from pocket bottom to top and bottom of rim?
If you indicate off base and find pocket is 0.004 shallow you are now going to remove 0.004 brass from the case head. At the same time reducing the flash hole depth by that same amount.
What if you had ref off the top of rim and found it was consistent with other cases?
Now would we need to measure case head thickness at the flash hole to see if that was consistent?
If you can measure depth of primer pocket and have a seater that is depth adj 0.001 and or seat by feel then pocket depth should not be a major issue unless it's so out of spec it prevent seating below flush.

For me I would rather cull/sort then mess with going thru all that for what amounts to a crap shoot for gain/loss.

I never mess with flash holes any more. Can not see how without wallowing at least some of the FHs. I will remove a chad or stuck chip. Otherwise, if I have an issue I can see or measure I cull. Always need cases for foulers and pressure test.

I do not want to explain my full reloading procedures and why because it's a bit off topic. But I will say I choose to cull and sort. I focus on maximizing consistency in areas proven to have effects.

Neck length (check and run into the preset trimmer everytime). Set gap based on neck growth per firing 0.005-0.003. (I hate giving room for carbon rings.) But there must be enough room for the flow understanding it contracts so you need a 2-3 thou more than measured.

Internal neck surface co friction. I have used powdered graphite for decades. Recently been testing hBN.

Neck compression force on the bullet. Interference fit measurement is popular and most people use this as a force conversion. It is not. This is especially true when dealing with brass and copper alloys. Virgin brass case neck at -0.002" interference force is different than once fired brass neck. A seated case neck force is less the same day its seated than it is the next day or in a week or two. A piece of brass that has just had displacement/flow is in a state of flux. Its not "settled". There is also a possible supported theory of very mild cold/compression welding or bonding over the long term. Having a low CoF substance barrier between neck and bullet surface prevents that as well as decreasing CoF and increase consistency of release.

Powder charge precision and consistency. I use a lab scale that can measure even kernel of ball.

Concentricity of neck& bullet to shoulder under 0.002. I admit to trying to get as low as possible but I can not say I see it on target. So chalk that up to precision for precision's sake. I go for under a thou.

Consistency of BTO as we have all seen what a few thou in jump/BTO can do to a group in tuning. Key to consistent measuring is a gauge that fits the bullet ogive.
 
what is the ref point to indicate off of and how does that effect all other critical areas.
You bring up valid points that lead to issues in seating w/resp to the case head.
If you would like to clear those issues and others (like individual primer height), just use an indicated K&M seater.
It compensates for everything at once, for each case/pocket/primer, and provides direct measure of crush.

And best of all, it shows you directly that you cannot do this by feel.
Nobody can -with ANY tool..
 
You bring up valid points that lead to issues in seating w/resp to the case head.
If you would like to clear those issues and others (like individual primer height), just use an indicated K&M seater.
It compensates for everything at once, for each case/pocket/primer, and provides direct measure of crush.

And best of all, it shows you directly that you cannot do this by feel.
Nobody can -with ANY tool..
The K&M tool is the one you want if your seating to depth and do not want to sort. My testing showed the primer wants to be seated to a certain amount of crush based off its original height. So if your primer lot varies by .004 and you just seat them all to a depth, you will have .004 variation in crush. So either you need to measure every one and sort into batches and adjust each batch to maintain crush or you use a tool like the K&M. Both are extremely tedious. The interesting thing is that after testing a primer for the crush it shot best and comparing that to where they end up if you seat by feel, they end up in the same place. While we could hold a slightly better tolerance using a tool that seats by depth, we could not see it on target. And there was a lot of work to make it work. My point on this subject has always been that you can literally shoot sub 2" groups at 1k seating by feel, you can break year long aggregate group records seating by feel. This is not holding back your hunting rifle. I think its a road that extremely accomplished shooters need to explore because at some point everything matters. But when it comes to this topic, its so small we cant see it. Maybe once we can shoot under an inch we can who knows. Lots of good tools out there but you have to understand what a primer wants and know how the tools work.
A very big part of my business is guiding my customers to their accuracy goals. I dont charge for it, its part of the support after I build the rifle. You want them to shoot, loading and tuning is a huge part of that. To this day I have yet to find a customer whos method of primer seating has held them back from their accuracy goals. From hunting rifles to record breaking competition rifles.
I am not saying any of these tools are bad, I have used all of them in this thread I believe. And they are all very good at what they do. I think some are faster, some are more ergonomic, some are better made, ext.
 
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My testing showed the primer wants to be seated to a specific measurement from the bolt face/ignition system.

Consequently, the CPS has the power to uniform the primer height during the seating op, thus, bringing the same dimension to ALL, no matter where they start. Done correctly, this eliminates any need to monitor "crush". However, for those that would like to do it that way, the absolute best method to achieve it is provided by a CPS with Bryan Blake's CPS plate and measuring system.

I haven't been able to convince any of our benchrest customers to come forward and officially endorse the CPS being used as I describe... as they'd prefer it remain secret. However, Jason Wolf wrote a wonderful testimonial for us... and for 2 years straight, he was winning quite handily in benchrest. There sure are a lot of apex level benchrest shooters running CPS's... but no one would know it because they don't say a peep about it. If their match attendance numbers are any indication, benchrest just isn't growing... and their lack of social graces can take the blame for it. Everyone's tired of that kind of attitude among shooters. Alex comes and talks all over... but who else? haha

F-class is another story, finally. We have several of the most-winning shooters in the nation (world) doing things exactly as I describe, and saying so. Wins are being stacked up all the time, and while I think that is cool... the real message here is more consistency. Which is exactly what our equipment and methodology provides. With any luck if schedules permit I'll be conducting a few interviews in the coming months with those shooters which will have some of you changing the way you're doing things.

There will be those that will not change a thing, and that's to be expected, as people are given great advice that they ignore all the time. They'll never admit it. They'll never change. They'll just get more bitter and fade away... just like always.


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My testing showed the primer wants to be seated to a specific measurement from the bolt face/ignition system.

Consequently, the CPS has the power to uniform the primer height during the seating op, thus, bringing the same dimension to ALL, no matter where they start. Done correctly, this eliminates any need to monitor "crush". However, for those that would like to do it that way, the absolute best method to achieve it is provided by a CPS with Bryan Blake's CPS plate and measuring system.

I haven't been able to convince any of our benchrest customers to come forward and officially endorse the CPS being used as I describe... as they'd prefer it remain secret. However, Jason Wolf wrote a wonderful testimonial for us... and for 2 years straight, he was winning quite handily in benchrest. There sure are a lot of apex level benchrest shooters running CPS's... but no one would know it because they don't say a peep about it. If their match attendance numbers are any indication, benchrest just isn't growing... and their lack of social graces can take the blame for it. Everyone's tired of that kind of attitude among shooters. Alex comes and talks all over... but who else? haha

F-class is another story, finally. We have several of the most-winning shooters in the nation (world) doing things exactly as I describe, and saying so. Wins are being stacked up all the time, and while I think that is cool... the real message here is more consistency. Which is exactly what our equipment and methodology provides. With any luck if schedules permit I'll be conducting a few interviews in the coming months with those shooters which will have some of you changing the way you're doing things.

There will be those that will not change a thing, and that's to be expected, as people are given great advice that they ignore all the time. They'll never admit it. They'll never change. They'll just get more bitter and fade away... just like always.


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My hope was that the seated depth would be what shot best. That would have meant I would not have to sort primers by height. But thats not what my targets showed. I know Jason Wolf, I do his work. Call him and ask him if your tool improved his accuracy. He won the 600yd Nats 2 years in a row. The first year he seated by feel the second he used the cps. Same barrel, powder, bullets, gun, ext. Do not get me wrong. Im not cutting it down. Its a good tool if used right. Its well made and excellent for guys with hand trouble. Lots of guys have bought them on my recommendation. I will continue to recommend them to people so long as they understand them. But I will not tell them it will shrink their groups. Sorry. And yes, your right I do get on here and talk. Many BR shooters used to as well but they get tired of guys that do not do the testing and compete at that level telling them they are wrong. Before you mention anything more about Benchrest and its social graces, I personally would like to invite you to come and shoot a match at Deep Creek. I will provide a rifle and ammo. I guarantee you will change your opinion once you attend a match.
 
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Alex did you put a new Avatar on or maybe I was not looking close enough??? Looks great.

A lot of different opinions included in these threads on Primer Pockets, Seating, Flash Holes. All good information to think about.

Maybe after I get this next neck operation done (hopefully it works) Jill and I can come out to the Great State of Montana f or a visitand sling some lead at your ranges and Matches.

Thanks
Len & Jill
 
My testing showed the primer wants to be seated to a specific measurement from the bolt face/ignition system.

Consequently, the CPS has the power to uniform the primer height during the seating op, thus, bringing the same dimension to ALL, no matter where they start. Done correctly, this eliminates any need to monitor "crush". However, for those that would like to do it that way, the absolute best method to achieve it is provided by a CPS with Bryan Blake's CPS plate and measuring system.

I haven't been able to convince any of our benchrest customers to come forward and officially endorse the CPS being used as I describe... as they'd prefer it remain secret. However, Jason Wolf wrote a wonderful testimonial for us... and for 2 years straight, he was winning quite handily in benchrest. There sure are a lot of apex level benchrest shooters running CPS's... but no one would know it because they don't say a peep about it. If their match attendance numbers are any indication, benchrest just isn't growing... and their lack of social graces can take the blame for it. Everyone's tired of that kind of attitude among shooters. Alex comes and talks all over... but who else? haha

F-class is another story, finally. We have several of the most-winning shooters in the nation (world) doing things exactly as I describe, and saying so. Wins are being stacked up all the time, and while I think that is cool... the real message here is more consistency. Which is exactly what our equipment and methodology provides. With any luck if schedules permit I'll be conducting a few interviews in the coming months with those shooters which will have some of you changing the way you're doing things.

There will be those that will not change a thing, and that's to be expected, as people are given great advice that they ignore all the time. They'll never admit it. They'll never change. They'll just get more bitter and fade away... just like always.
I'm trying to understand if these top level shooters are indeed using your equipment then why wouldn't they share that information? Kinda like when some advertise the barrels they shoot or stocks, brass, bullet companies they are running.
 
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Alex did you put a new Avatar on or maybe I was not looking close enough??? Looks great.

A lot of different opinions included in these threads on Primer Pockets, Seating, Flash Holes. All good information to think about.

Maybe after I get this next neck operation done (hopefully it works) Jill and I can come out to the Great State of Montana f or a visitand sling some lead at your ranges and Matches.

Thanks
Len & Jill
No, its the same. Just some country south of here about 45 minutes but most of it looks the same. We were after mule deer that trip. Its was a draw tag and a buddy had one. Even though its a draw, theres not many good bucks or bulls for that matter.
 
I'm trying to understand if these top level shooters are indeed using your equipment then why wouldn't they share that information? Kinda like when some advertise the barrels they shoot or stocks or what brass they are running.
In some cases certain guys will think they have a "secret" and lie on an equipment list or lie about their process. This is pretty rare since there really are no secrets. Once you have a good rifle it comes down to the tune. And your tune is not going to work in your competitors rifle. Some guys just like to feel like they have a secret edge. Personally, I do not deal with liars. If I knew a guy was lying about any of the above. He'd need to find a new smith. Thats something I have no tolerance for. Luckily, it has never happened. But yes, I have heard of it.
 
In some cases certain guys will think they have a "secret" and lie on an equipment list or lie about their process. This is pretty rare since there really are no secrets. Once you have a good rifle it comes down to the tune. And your tune is not going to work in your competitors rifle. Some guys just like to feel like they have a secret edge. Personally, I do not deal with liars. If I knew a guy was lying about any of the above. He'd need to find a new smith. Thats something I have no tolerance for. Luckily, it has never happened. But yes, I have heard of it.
My principles as well. IME, dishonesty is the most toxic action in a society. Honesty is the foundational cornerstone of ethics and morals. Without it everything else crumbles.

Thank you for being willing and taking the time to share the hard earned knowledge you have. When people at your level and experience choose to do this it increases the collective knowledge of the entire community. At least for those willing to be objective and reflective vs wanting to be correct. I prefer to prevent wasted action repeating that which has already be tested and shared. I have more discretionary time than most, regardless, I do not wish to waste it.
 
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My principles as well. IME, dishonesty is the most toxic action in a society. Honesty is the foundational cornerstone of ethics and morals. Without it everything else crumbles.

Thank you for being willing and taking the time to share the hard earned knowledge you have. When people at your level and experience choose to do this it increases the collective knowledge of the entire community. At least for those willing to be objective and reflective vs wanting to be correct. I prefer to prevent wasted action repeating that which has already be tested and shared. I have more discretionary time than most, regardless, I do not wish to waste it.
I like to see guys shoot well. Especially hunters since the game pays the price if they don't. I met a guy last weekend hunting elk. We had spotted them at the same time and tried to make a play on them. I asked how far he could shoot. The answer was I have a brand x long range hunter so I'm good to 800yds but have never shot that far. That kind of thing is so common because that's how they advertise stuff. I'm fortunate to be somewhere I can shoot a lot at long range and I like to test a lot because small groups are my hobby. And because I don't believe in secrets, I believe in work, I don't feel like I'm giving away anything. The best shooters will still test everything themselves.
 

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