Lapua 220 Russian Primer pocket test

P.Ericson said:
As well as having a FL die that size enough, I think it´s also a matter of sizing the case all the way to the bottom of the body. Several dies I have seen have such a big radius cut that they leave ~.100" of unsized brass at the bottom of the case... Not good!
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I have been able to prove that what Mr. Ericson has just posted to be the most important part of a any Very Good sizing die. If the die does not size all the way into the extraction groove of the sized case. I can take a full sized 6 PPC case from any very good Full length 6 PPC die that sizes the correctly (.0012) at .200 from bolt face. If that die does not size the case into the extraction groove shooting the super hot loads it WILL develop a small ridge just above the extraction groove causing the dreaded bolt click. I have proved it on more that just a few different shooters guns.

Chet

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Some years back I did a little experiment along the same lines. One of my test cases had developed a click. The die that I use is one of the Harrell's Vari-base dies with interchangeable inserts (in .001 increments) in the base of the die. I had previously had the shell holder shortened by about .013 to get it out of the way when working with work hardened brass. The base inserts have almost no chamfer/radius. Taking a risk, I simply unscrewed the bushing to the point where it just touched the shell holder and the click disappeared. This whole die coverage vs. chamber coverage issue has been largely ignored in favor of going the small base route which IMO does not get to the root of the problem. Another solution that I have would work a lot better if I had a lathe so that I could turn down the rims of cases a couple of thousandths.It is a base die with no shoulder and a pusher that goes in the ram in place of the shell holder. Currently when I have tried it the case would be stopped when the rim hit the sizing ring. At that point a punch would have to be used to remove the case. I should also add that this is no place to use marginal case lube. I don't know how critical capacity is for the PPC and whether it would be practical in terms capacity to burning rate/density considerations go, but if you were to short chamber, use a shortened shell holder, and shorten a regular die, I think that the needed sizing coverage would be easily available. I have no idea what the accuracy result would be.
 
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coyotechet said:
I have been able to prove that what Mr. Ericson has just posted to be the most important part of a any Very Good sizing die. If the die does not size all the way into the extraction groove of the sized case. I can take a full sized 6 PPC case from any very good Full length 6 PPC die that sizes the correctly (.0012) at .200 from bolt face. If that die does not size the case into the extraction groove shooting the super hot loads it WILL develop a small ridge just above the extraction groove causing the dreaded bolt click. I have proved it on more that just a few different shooters guns.

Chet

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HAAiiiii CaRAM'baa!! A tool I don't have!!!

You musta' made that one,

I went another way.....saying "why fix it?" I say just ignore it, make enough clearance,

can anyone say FAT BUTT??

(anyone who thinks they can "contain" the casehead using a tight chamber/boltface is foolin' theyselfs)
 
Chet, you sly old dog you!!

you are exactly right on the money! The die needs to come down on the web for sure to shoot hot loads.
That's what my die does and why the brass lasts for about forever.
Doc Peterson, I go a little smaller on the web to .440-.4398 Probably not alot of difference in what were doing.

Some people just don't realize how important all this is. Well, maybe they do but don't know how to correct the issue.
Not saying there isn't some softer brass out there but the Lapua isn't as bad as some make it out to be.
And heck, I guess that's all there is to it:rolleyes:

Richard
 
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Some people just don't realize how important all this is. Well said:
You are so right, Richard, you understand this stuff to the nth degree. Isn't it nice when everything is right with the chamber, sizing die and die adjustment? In my opinion, Lapua gets blamed for lots of stuff that has nothing to do with the case. Rumors get started by someone who doesn't know what he's doing and then get blown all out of proportion. Keep up the good work my friend!

Gene Beggs
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Also, and this may seem like a small point....but it ain't!

I have pushed for a LOT of Harrell dies in my day, especially for getting feet-wet, and for many (most) people they will be sufficient forever BUT, it must be said, when shooting HOT and going for long case life only a Neil Jones style n/s bushing or a solid one-piece die will do. Unless one gets kinda lucky (or wicked canny) MOST Bushing style setups will leave a tiny un-sized ring at the neck/shoulder junction.

If one owns a chambering reamer with a fair radius at the n/s junction, the Harrell might will work...... Or if one is set up so that the knife edge of the bushing step is very nearly the same as the neck size...... (this kinda' defeats the whole purpose of the bushing die) ..... or sometimes a combination of shoulder-bounce and upside-downey bushes gets 'er done..... but most often the replaceable bushing setup falls a wee short for truly long caselife.

Some die-makers leave a .080 or .100 land area for the bushing seat, and again some are sized so scrupulously for typical turned neck cases that they act as a one-piece die, but the problem is then that adjusting tension is iffy.

I basically don't use "buttons" any more
 
Loose primer pockets...?

I quit BR 6 or 7 years ago, but I always went to a match with 15 once fired cases and shot the entire match with them. My recollection is that by Sunday afternoon I was having problems seating primers...tight!
H322 at just under 3350 fps. Cases seemed to be convex on the case head--flattening out and tightening the primer pocket with repeated firings.
Goes against conventional reasoning.
 
Bryan, many of us went through the exact same thing. After a while, you could hardly get the primers in. The cases definetally had a convex face.

I cured that by facing the cases flat. But then, Lapua stated making their cases flat again.

I haven't checked the cases that are experiencing loose primers. They might be concave, which would tend to loosen the pockets.
 
Jackie, Could an enterprising shooter of very hot loads make a lathe fixture to put a little convex on heads to counteract a loosening primer pocket issue? Boyd
 
Boyd Allen said:
Jackie, Could an enterprising shooter of very hot loads make a lathe fixture to put a little convex on heads to counteract a loosening primer pocket issue? Boyd
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Set a lathe compound to your desired angle cut to produce a desired concave cone, probably somewhere between 1and 2 degrees for a several thou of depth cut, would have to trig. calculate the exact angle relative to PPC casehead dimensions.

Why do you think the PPC is convex as opposed to concave?..............Don
 
Proper sizing die dimensions

P.Ericson said:
As well as having a FL die that size enough, I think it´s also a matter of sizing the case all the way to the bottom of the body. Several dies I have seen have such a big radius cut that they leave ~.100" of unsized brass at the bottom of the case... Not good!
Click to expand...

The body of the sizing die should come very close to sizing the entire body of the case, although it isn't necessary to size "right up" to the extractor groove. If you find that you must have a case sized that far down the body, there is a chance that you don't have enough clearance between the bolt nose and the barrel breech/cone. The clearance should be 0.008 to 0.010". In my experience, the FL die for PPC cases must be 0.003" under the diameter of the chamber (0.0015" per side) to size the case sufficiently to eliminate the "bolt click" at the start of the extraction cam. Furthermore, I've found that most shooters get the sticky extraction from pushing the shoulders back excessively, rather than not having a small enough sizing die.
 
Don said:
Set a lathe compound to your desired angle cut to produce a desired concave cone, probably somewhere between 1and 2 degrees for a several thou of depth cut, would have to trig. calculate the exact angle relative to PPC casehead dimensions. Why do you think the PPC is convex as opposed to concave?..............Don
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My question was based on someone having said that in the past there had been issues with pockets tightening because the heads were concave. My thought was to recreate that situation to combat loosening of primer pockets. I do not think that they are either convex or concave, and I have not had any problems with pockets, probably because I have never routinely shot loads over 30 grains of 133.
 
Boyd Allen said:
Jackie, Could an enterprising shooter of very hot loads make a lathe fixture to put a little convex on heads to counteract a loosening primer pocket issue? Boyd
Click to expand...

Back when we were shooting the Sako .220 Russian brass with the balloon heads, Red Cornelison did exactly that to tighten up his primer pockets. I think he set his compound on a half degree and faced his. Are head out from the center in the lathe. I was shooting a Waldog at Midland at the Nationals one year and picked up the cartridge off the loading bench and the primer stayed on the bench. Figured it was time to make some new brass. Making Waldog brass was one of my least favorite jobs.
 
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