Problem with primers backing out.
.257 Roberts. New and once fired Remington brass and CCI 200 primers. IMR 4320 and 100 gr. Sierra SPBTs. Doesn't matter what charge I put in them. Low end all the way to just under max the primers back out the same in all of them. Haven't actually measured but just by looking at them they look the same. Accuracy is very nice with this load at 38.5 grains. Why would the primers move like this? They didn't with the 40 rounds of Hornady factory loads I've put through it. Will be trying WLR primers next.
Is it even a problem if everything else is working right?
Is it even a problem if everything else is working right?
0
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Could you be sizing your brass too much and creating a headspace problem or possibly seating the bullets out too far and creating excess pressure? Even with a light load a bullet in the rifling is not a happy camper. Just a thought. 0 -
excess headspace or over-sizing the case. Back the die off and see if it goes away. Use a fired case, set it in the shellholder, and remove the decapping stem. Run the die down by hand until it makes contact with the shoulder. set the die there and re-install the decapping rod. Load and fire and see if the situation goes away. 0 -
B17-P51,
Not seating too far out. It's a Remington 722 so it won't let me if I want to put them in the magazine. Good thought though.
JustC,
I will try the sizing trick.
By the way, I measured them and they are backed out .008" on everyone I checked.0 -
Sizing die set to close to shell holder for YOUR CHAMBER 0 -
quote:Originally posted by JustC
excess headspace or over-sizing the case. Back the die off and see if it goes away. Use a fired case, set it in the shellholder, and remove the decapping stem. Run the die down by hand until it makes contact with the shoulder. set the die there and re-install the decapping rod. Load and fire and see if the situation goes away.
JustC, I don't envision how this would be possible- to run the die down by hand??? It takes hundreds of pounds of compounded force to size the case- not something I could od by hand. And even if I could, it wouldn't come out of the die easily. Perhaps you could elaborate?
What I would do is soot a case that's been fired, lube it, screw the sizing die in to the shellholder then back of about 5 turns. Size the case. Observe the neck. Repeat, screwing the die in a half turn at a time until the neck is entirely sized. This should be about right and won't push your shoulder back.0 -
ID-Your cases are to short to fit the chamber in the proper way..
Adjust your die to your chamber and the problem will disappear
jonk--Justin meant to screw the die down by hand after you loosen the darn set screw
in the ring that holds the die in place.....0 -
quote:Originally posted by mrbruce
ID-Your cases are to short to fit the chamber in the proper way..
Adjust your die to your chamber and the problem will disappear
jonk--Justin meant to screw the die down by hand after you loosen the darn set screw
in the ring that holds the die in place.....
Aaah. Gotcha.0 -
quote:Originally posted by idahoducker
.257 Roberts. New and once fired Remington brass and CCI 200 primers. IMR 4320 and 100 gr. Sierra SPBTs. Doesn't matter what charge I put in them. Low end all the way to just under max the primers back out the same in all of them. Haven't actually measured but just by looking at them they look the same. Accuracy is very nice with this load at 38.5 grains. Why would the primers move like this? They didn't with the 40 rounds of Hornady factory loads I've put through it. Will be trying WLR primers next.
Is it even a problem if everything else is working right?
Hi idahoducker,
You have created a headspace problem without even knowing it. There is a very important relationship between the rifle's headspace and the die-to-shellholder distance. These two dimensions must relate to each other or there will be too much or too little headspace. To gain an understanding of this relationship, there is a simple gauge that is available from RCBS. It is called the Precision Mic and is available for every cartridge known to man. I will quote from Cabela's website......
The Precision Mic Gauge shows you your chamber headspace and bullet-seating depth to 0.001 of an inch with just a few twists. It measures from the datum point on the case's shoulder to the base, giving you spot-on SAAMI tolerance readings. It's indispensable for safe, accurate loads. Available for many popular calibers.
You will be able to properly set the die to attain the proper headspace for your rifle with this gauge. It is very important to understand the relationship between the rifle's headspace requirements and the die's position in relation to the shellholder. The amount of case head to bolt face pressure will be greatly reduced once you have attained proper headspace. Your brass will last for a very long time also because it will not be stretching excessively. And your primers will be flat in the pockets too! The old saying of 'screw the die down until it bottoms out on the shellholder and then back it off an 1/8 of a turn' will always get a reloader in trouble.
The other important attribute that the gauge has is solving the bullet seating depth. The gauge is capable of relating the chamber-to-land distance to the proper setting of the bullet seating die. You will be able to seat your bullets properly and record the relative value that the gauge will give you.
I would highly recommend that you at least read about the gauge and become familiar with its attributes. The gauge will resolve all of your press setup issues. I always purchased one prior to setting dies in my Dillon. They were always a must tool in my reloading room.
I trust that this information will be helpful to you.
Matt0 -
jonk,..yeah that's what I meant. You put a fired case in the shellholder, and run the press ram up to the top. Then, after loosening the lock ring, THREAD the die in by hand until the inside of the die body and the fired shell shoulder make contact. You will know this becasue the die will stop. Now, re-set the lock ring, re-insert the decapping stem, and size the cases. That should set them at the exact size of the chamber. You can then use a headpsace tool to determine the length of the case from casehead to datum line. Then you can advance the die down little by little until the shoulder is juuuussst pushed back by maybe .001"-.002" if you wish, or you can run with the original setting until the cases become difficult to chamber, then run the die down just a tad to push the shoulders back.
Sorry for any confusion,..my fingers can't keep up with my thoughts and sometimes I don't fully explain before moving on to the next though[B)]
I use the stoney point "head and shoulders" guage. It is now owned and produced by Sinclair I beleive. They are cheap, come with inserts for every size case, and cost a lot less than buying one for each chambering. One set does them all[;)]
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You could also get a simple case guage from Lyman for the particular caliber you are concerned about and use it to adjust your sizing die to size the cases to proper dimensions. You might also get a headspace gage or gages for your rifle or take it a good gunsmith and have him check the rifle for proper headspace. Better yet, get a neck sizing die and since your cases will be fire formed to your chamber when fired use it alone to sized the neck and leave the other dimensins alone once formed.
Larry[8D]0 -
quote:Originally posted by dardascastbullets
quote:Originally posted by idahoducker
.257 Roberts. New and once fired Remington brass and CCI 200 primers. IMR 4320 and 100 gr. Sierra SPBTs. Doesn't matter what charge I put in them. Low end all the way to just under max the primers back out the same in all of them. Haven't actually measured but just by looking at them they look the same. Accuracy is very nice with this load at 38.5 grains. Why would the primers move like this? They didn't with the 40 rounds of Hornady factory loads I've put through it. Will be trying WLR primers next.
Is it even a problem if everything else is working right?
Hi idahoducker,
You have created a headspace problem without even knowing it. There is a very important relationship between the rifle's headspace and the die-to-shellholder distance. These two dimensions must relate to each other or there will be too much or too little headspace. To gain an understanding of this relationship, there is a simple gauge that is available from RCBS. It is called the Precision Mic and is available for every cartridge known to man. I will quote from Cabela's website......
The Precision Mic Gauge shows you your chamber headspace and bullet-seating depth to 0.001 of an inch with just a few twists. It measures from the datum point on the case's shoulder to the base, giving you spot-on SAAMI tolerance readings. It's indispensable for safe, accurate loads. Available for many popular calibers.
You will be able to properly set the die to attain the proper headspace for your rifle with this gauge. It is very important to understand the relationship between the rifle's headspace requirements and the die's position in relation to the shellholder. The amount of case head to bolt face pressure will be greatly reduced once you have attained proper headspace. Your brass will last for a very long time also because it will not be stretching excessively. And your primers will be flat in the pockets too! The old saying of 'screw the die down until it bottoms out on the shellholder and then back it off an 1/8 of a turn' will always get a reloader in trouble.
The other important attribute that the gauge has is solving the bullet seating depth. The gauge is capable of relating the chamber-to-land distance to the proper setting of the bullet seating die. You will be able to seat your bullets properly and record the relative value that the gauge will give you.
I would highly recommend that you at least read about the gauge and become familiar with its attributes. The gauge will resolve all of your press setup issues. I always purchased one prior to setting dies in my Dillon. They were always a must tool in my reloading room.
I trust that this information will be helpful to you.
Matt
Sounds good, but not the way to go. If you really are having a headspace problem, the best tool made is the Stoney Point. It works just like a bullet comparator, and measures to the datum line. You'll need to use at least a once fired case-neck sized only, twice fired is better as you will get spring back on a once fired round (some will go three or four times). Then set your shoulder bump or set back 0.001-0.002 from this figure for this gun.I am assuming you are firing from a bolt gun. Be sure you are not "jam" seating your sierra's. Speaking of Sierra's, your load is HOT. Sierra lists 38.0 gr IMR-4320 as a max load, start load is 32.0gr. Sierra lists accuracy load as 42.5 of H4350. The first thing should be to reduce this hot load, but you'll need to set your dies correctly for full potential. I must agree with Glen D. Zediker,author: HANDLOADING FOR COMPETITION, when he stated on page 124, "In case anyone is wondering why I didn't mention the RCBS Case Micrometer,there, I just did." This was the nicest was he could say it. Get the right tool to start with, you'll be glad you did.0 -
One last point regarding your hot load, all the Sierra load data, was done with 210M primers, usually the CCI200 is not as "hot" as a 210, (May 1984 American Rifleman), but still I'd like to hear what happens when you start with the start load. Best accuracy and best velocity load are with much slower powders. 0 -
Idahoducker,
All of us have an opinion about which piece of gear works the best. If there were only the one that worked there wouldn't be any competition and a choice of products. Do some reading about the various methods of measuring cases and adjusting your dies then go back to shooting. Let us know how it all works out!
Best.
MEMPHISJOE,
"I am assuming you are firing from a bolt gun."
You have no idea what kind of firearm he is using. You have no idea what the condition is of his barrel or chamber. You don't know anything except the components of his load and then you don't know the exact seating dimension of the bullet in the case. And yet you contend that his load is `hot' based on your one reloading manual reference.
What you don't know is that individual rifles don't all operate at the same pressure level. Some don't handle all of the loads within the load range and show early signs of pressure. Others continue to operate at what we think is the high end of the pressure range without showing adverse signs of pressure. Sometimes a particular lot number of a specific powder doesn't perform at the burn rate that the manufacturer suggests and runs higher or lower on the pressure curve.
What you also don't seem to know is that the .257 Roberts has three ranges of pressure set up by SAAMI for various grades of firearms that can be achieved through basic reloading.
The load that is being discussed falls well within the lowest range of pressure so it can't really be called `hot'. It's simply at the top of the scale that Sierra is using currently for their load manuals without specifying that these are the lowest pressure loads. I have another Sierra manual that lists the range as being 34.5 gr. to 38.6 gr. and it still falls well within the lowest pressure range. One of my Hodgdon manuals has the range as being 36.0 gr. to 39.0 gr. for IMR-4320. On and on, it's like quoting statistics because it depends on who's doing the testing and measuring, which type of pressure gun they're using or if they're constructing a model with a computer program. There are lots of variables.
Reloading manual are great repositories of a massive amount of data constructed through testing and nowadays, computer modeling. But the ranges are used as guidelines not necessarily hard and fast absolutes. There are far too many variables that can be taken into account for each individual rifle. That's why we run all these tests on components and loads to see what each rifle likes for accuracy.
Best.0 -
quote:Originally posted by nononsense
Idahoducker,
All of us have an opinion about which piece of gear works the best. If there were only the one that worked there wouldn't be any competition and a choice of products. Do some reading about the various methods of measuring cases and adjusting your dies then go back to shooting. Let us know how it all works out!
Best.
MEMPHISJOE,
"I am assuming you are firing from a bolt gun."
You have no idea what kind of firearm he is using. You have no idea what the condition is of his barrel or chamber. You don't know anything except the components of his load and then you don't know the exact seating dimension of the bullet in the case. And yet you contend that his load is `hot' based on your one reloading manual reference.
What you don't know is that individual rifles don't all operate at the same pressure level. Some don't handle all of the loads within the load range and show early signs of pressure. Others continue to operate at what we think is the high end of the pressure range without showing adverse signs of pressure. Sometimes a particular lot number of a specific powder doesn't perform at the burn rate that the manufacturer suggests and runs higher or lower on the pressure curve.
What you also don't seem to know is that the .257 Roberts has three ranges of pressure set up by SAAMI for various grades of firearms that can be achieved through basic reloading.
The load that is being discussed falls well within the lowest range of pressure so it can't really be called `hot'. It's simply at the top of the scale that Sierra is using currently for their load manuals without specifying that these are the lowest pressure loads. I have another Sierra manual that lists the range as being 34.5 gr. to 38.6 gr. and it still falls well within the lowest pressure range. One of my Hodgdon manuals has the range as being 36.0 gr. to 39.0 gr. for IMR-4320. On and on, it's like quoting statistics because it depends on who's doing the testing and measuring, which type of pressure gun they're using or if they're constructing a model with a computer program. There are lots of variables.
Reloading manual are great repositories of a massive amount of data constructed through testing and nowadays, computer modeling. But the ranges are used as guidelines not necessarily hard and fast absolutes. There are far too many variables that can be taken into account for each individual rifle. That's why we run all these tests on components and loads to see what each rifle likes for accuracy.
Best.
As there was no statement either way on what type of rifle, I had to make an assumption, what you don't know is what type of rifle he is using, what you did not do is make an educated guess.
What you do not seem to grasp is he has primers backing out, this is usually a sign of excess pressure, the safe thing to do is to reduce pressure, regardless, of the cause until the problem can be solved. What you do not know is that regardless of what pressure you believe his rifle should be operating at, it is backing out primers, should and is are two different things. Regarding you rant on SAAMI pressure standards, I would like you to post this special data you seem to have, the special data only SAAMI sends you! In my copy of the standards, there is indeed three different bullet weights listed, but lets be no nonsense here, there is only one set of pressure, the same set of pressure for all three weights, 87,100,117gr bullets. We are not talking about +p here, just the lising in the spec. Please post the page where this is listed, if you know. Safe and careful loading should always put the shooter first, lets cut the non sense here and say any time you are backing out primers, regardless of the cause, you have a pressure problem..reduce the load. What you don't know is most serious loaders use a stoney point, or like gauge to measure their cases head space. What you don't know is sometimes there is only one thing that works...correctly that is. The RCBS whiz is not the way to go. You need to do a little reading on the subject, you may wake up and say.."wow, what I did not know, I did not know I didn't know it".
idahoducker..do not let this crap get you to do something unsafe, reduce the load, and get a stoney point gauge, work the load back up, you may be able to go to a much high load than what is backing out your primers now, but be safe we do not need someone hurt, because someone thinks you should start hot based on an old manual. Sierra is often on the safe side, but that is where you want to start, safe sided. What nononsense does not understand is when you have primers coming out, you are on the hot side. Good shooting, also please post what type of rifle your shooting.0 -
post 0 -
MEMPHISJOE,
"What nononsense does not understand is when you have primers coming out, you are on the hot side."
From Sierra's Exterior Ballistics.com page:
Backed-Out Primer: A primer which, upon firing, has been pushed slightly out from the primer pocket. Primers backing out generally indicates an excessive headspace situation, usually in conjunction with a light load. Can be caused by light loads alone, in some circumstances. Also referred to as a popped or protruded primer.
http://www.exteriorballistics.com/reference/glossary.cfm
As a simple explanation:
This is a very normal occurrence when peak pressure is far below the normal, maximum amount. What happens is the case is pushed forward by the firing pin as the primer is struck. When the case expands to fill the chamber, the lower-than-normal pressure isn't enough to push the back of the case fully against the bolt face. But the primer isn't held in place with much tension, so it gets pushed back against the bolt face. In the opposite situation, maximum pressure in a cartridge pushes the case head hard against the bolt face leaving no place for the primer to stick out its pocket, resulting in very flattened primers. In extreme situations you might even see some cratering.
SAAMI Specifications for the .257 Roberts:
Piezo
SAAMI = 54,000 PSI
CIP = 51,000 PSI
Copper Crusher
SAAMI = 45,000 CUP
CIP = 45,000 CUP
The load specified above is less than the 45,000 CUP specified by SAAMI and CIP.
None of the members here at GB advocate unsafe practices or loads. We do advocate accurate information.
You can slander me if you want but all of the experts, even Sierra, agree with the position that I've stated.
There is no more to be written, we're finished here.
Best.0 -
quote:Originally posted by nononsense
MEMPHISJOE,
"What nononsense does not understand is when you have primers coming out, you are on the hot side."
From Sierra's Exterior Ballistics.com page:
Backed-Out Primer: A primer which, upon firing, has been pushed slightly out from the primer pocket. Primers backing out generally indicates an excessive headspace situation, usually in conjunction with a light load. Can be caused by light loads alone, in some circumstances. Also referred to as a popped or protruded primer.
http://www.exteriorballistics.com/reference/glossary.cfm
As a simple explanation:
This is a very normal occurrence when peak pressure is far below the normal, maximum amount. What happens is the case is pushed forward by the firing pin as the primer is struck. When the case expands to fill the chamber, the lower-than-normal pressure isn't enough to push the back of the case fully against the bolt face. But the primer isn't held in place with much tension, so it gets pushed back against the bolt face. In the opposite situation, maximum pressure in a cartridge pushes the case head hard against the bolt face leaving no place for the primer to stick out its pocket, resulting in very flattened primers. In extreme situations you might even see some cratering.
SAAMI Specifications for the .257 Roberts:
Piezo
SAAMI = 54,000 PSI
CIP = 51,000 PSI
Copper Crusher
SAAMI = 45,000 CUP
CIP = 45,000 CUP
The load specified above is less than the 45,000 CUP specified by SAAMI and CIP.
None of the members here at GB advocate unsafe practices or loads. We do advocate accurate information.
You can slander me if you want but all of the experts, even Sierra, agree with the position that I've stated.
There is no more to be written, we're finished here.
Best.
WHERE ARE YOUR POSTS FOR THE THREE DIFFERENT SETS OF PRESSURE DATA YOU HAVE FROM SAAMI? They do Not exist,except in you mind. I believe you are confused, there is not three different sets of pressure data for this one round. It just sounded good, so you posted it. You keep on advocating the RCBS whiz tool, as the way to go. Others may not call your hand, but will know this is a poor choice, very poor choice. Why would you quote Sierra, when you think their data is too safe? You posted that you had some old data, and thought it would be just as good as the newest data. Because if it as ever published, it must be great, do not go the the lastest data, stick with the oldest stuff you can find, if you like..this is crazy. I guess you are now aware that he is loading a gun with a bolt anyway, and have discounted the one off recoilless rifle. How did you figure that out? I made a an assumption, and stated that I assumed, he was shooting a bolt gun. You are assuming a gun with a bolt! Keep on advocating the RCBS whiz tool, old data that is hotter than that published today for some one having trouble. I too agreed the man was having a head space problem, but instead of going with the whiz tool, gave him advice to use a tool that would actually help, very accurate and easy to use. You support of the whiz tool is what I'd expect from a pompus fool. I'm still waiting for the three different sets of pressure data for the 257Rob, not +P, not Ack Imp, but the 257Rob. As you have special inside info that SAAMI only shares with you, maybe it is to special to share. Or maybe you just pulled that crap out of your....0 -
post 0 -
I have run loads into the 80K psi range without knowing it ahead of time, and have never seen a backed out primer. Backed out primers are headspace issues. Flattened primers and cratered primers as well as pierced primers point to hot loads.
Pressure makes the case expand to fit the chamber. If pressure were higher than standard, logic dictates it fills the chamber more completely, and with more force. That force is 360* around. Therefore, the casehead would be pushed against the boltface with even greater force. This makes it far from normal to see a backed out primer in a hot load, since the bolt-thrust would be even greater than normal. This would seat the primer harder and possibly even flatten it (high pressure sign). A small case and a large chamber is what makes a primer back out. And, if the load is HOT in an oversized chamber, you will see primer flattening where the primer starts to back out, but the thrust slamms the casehead against the boltface and not only re-seats the primer, but flattens it as well. In this case, you may also see the case=head seperation line after only 1-2 firings. A backed out primer is a normal or lower pressure load in a larger chamber than the case.0 -
quote:Originally posted by JustC
I have run loads into the 80K psi range without knowing it ahead of time, and have never seen a backed out primer. Backed out primers are headspace issues.
You to? I've seen primers come out visably shorter than they went in, due to high pressure (sooted up the case head too [:0] ), but never backed out due to HIGH pressure.
Now on a LOW pressure load, you'll see them backed out quite often.
The pressures have to get above IIRC 40,000psi before the case will stretch back aganst the bolt face.
Now, referance test chambers and "production" chambers: real pressure guns use barrels that are on the "tighter than normal" end of spec, with minimum "minus" chambers and short throats, all of which tend to increase the pressure results. Factory chambers, on the other hand, tend to run closer to max in all dimentions, esp the throats, which brings the pressures down (sometimes WAY down).
That said, I still don't recogmend exceeding "bullet makers spec" on the powder charge, as you don't have any real way of knowing where your at on the pressure curve (if it's that bad, have the barrel pulled, set back, and re-chambered with a min spec reamer).0 -
The rifle is a Remington 722.
Max load from the data I'm using is 39 gr. IMR 4320. I'll have to get back to you on just what source that was but I'm pretty sure it was for +P and I've been told by several people including my gunsmith that +P is fine in the 722.
The primers are backing out the same distance (.008) with any amount of IMR 4320. Within the range specified in my data of course.
So far since I started this thread I've backed the die up in increments to a half turn. One round at each point. At 20/1000 the primer looked normal and you could see that it had made contact with the bolt face. I jumped to a half turn at that point and the primer backed out again. I haven't had a chance to try more yet but will this week.
Debates are great learning tools for those who are listening so please keep it up. Just be nice. [:)]0 -
Something just occured to me that I didn't connect before. All this about pushing the should back too far had me concentrating on only that. When I first bought the rifle you could see the very fine machine marks from the chamber on the fired brass. With 722/721s record of breaking extractors I asked my gunsmith about polishing the chamber. He agree it wouldn't hurt. If he happened to go a little too far with the polishing could that be causing the same problem? If I need to correct that I can get dies to match my chamber can't I?
Another thing. I'm getting sub MOA 5 shot groups with this thing as it is. Primers backing out and all. Is there anything really bad about having them back out just .008?0 -
No way the gunsmith "polished" out the chamber to any different size. That would take months of non-stop polishing with heavy grit polish. Unless he ran a reamer in it??? something you may wish to ask. If he ran a finish reamer into the chamber and did not set the barrel back, then that would definitely do it.
I would suggest you get a headspace tool like the stoney point (they are cheap) This way, you can set the dies to only bump the shoulder back by say .001" or you could buy a redding "body die" that sizes the body but leaves the shoulder alone. Either way, once fired, your cases when sized, will still have the same headspace dimensions. Oversizing after the first firing is what will cause that primer to back out since the shoulder is shy of the chamber shoulder by a fair amount.
Inquire as to whether he used a reamer or polish. if he used a reamer to clean up the chamber, THERE is your answer.0 -
I am glad you told us you were loading to +P specs! I was worried about loading 257Rob to 257Rob+P levels! These are two different cartridges, let there be no mistake about it, the +P brass is stronger and built for pressure levels 4000psi more than the original 257Rob (based on the 7x57 Mauser). I hope you are using brass so marked +P. Your action is very strong, no worries there, however; the weak link in any system is the cartridge brass. Regardless of what has been posted here several facts remain. High pressure can cause enlarged primer pockets. High pressure can cause loose primers. High pressure can cause a primer to fall all the way out of a case. Out of head space rifles, can have primer back out, or not, in the same rifle with the same load. If one of the cases has some lube on it, it may not grab the chamber wall and its reward thrust can reseat the primer that has backed out due to the pressure the primer has created. Low pressure, but poor head spaced rifles can flatten primer. OH YES, the primer starts out, then the case comes back to the bolt smashing the cup and making it look like a very over pressure load. A man named P.O. Ackley, did this type of work,he even blew up a couple of rifles to find out things like this, some people would be well served reading his fine book (now books vol I and II).
There is only one set of pressure data (SAAMI) for the 257Rob, it is reported in PSI, and CUP, this does not make two, but just two ways of measuring and reporting, as in most rounds. There is only one set of pressure data (SAAMI) for the 257Rob+P. Both have several bullet weights, but the data does not change. Anyone telling you otherwise is drinking again. The 257+p round is different (stronger) than the 257Rob round, when rounds are different they are different, meaning not the same. Men and women are both humans, but they are different, some of the old guys, have forgot about this... I stand by my original post regarding over loading for the 257Rob, but you are O-TAY with 257+P data (hope you are using +P brass). You are not having a problem with the factory loads are they +P, and your Rem brass not? I agree that you most likely have a headspace problem. And I like to be clear on this, those posters that are telling you to, (defending the use of), a RCBS whiz tool, either don't know, or do know and are for some weird reason giving you bad info!!! Get a Stoney Point Head Space Gauge, or like tool, and a good case gauge. You will be happier, your chance of making an error is much smaller.
If your "gunsmith" opened up your chamber-by whatever means, your chamber may be out of spec, causing the brass to shorten, as it swells to the chamber walls (the brass has to come from somewhere). If this is the case you need a new "gunsmith". Mic some of your fired cases even with spring back you may be able to find out if your chamber is too chubby. A chamber cast removes all doubt. The funny thing about this is you are having no problem with the Factory loads, My guess, and only a guess, would be if the chamber is to large, you would have the same problem with any full load. But then again if the factory brass is +P and your Rem brass is not, the strength difference may be just enough to fool you. I am glad you posted you are loading a bolt gun, some times you make assumptions I made the correct one, I even stated I was assuming you were loading for a bolt gun.0 -
post 0 -
Besides some guy having nothing to say about it in his book, what exactly is wrong with the RCBS mic? I did some research and found a lot of good user reviews. 0 -
Back in the day, the RCBS P-Mic was all there was. Like all tools, it has it's pro's and con's (the same can be said about the Stoney Point "head & shoulders" gauge).
I have one, and it does have a learning curve (just like anything else), but once you get the feel for it it works.
That said, I'm old school, and we always got the answers we needed WITHOUT resorting to "special tools" (we also learned how to change channels/adjust the volume without a remote, and were happy listening to the radio instead of a I-Pod). It might take a little longer, but you can get there without them.
Now MJ may blow a gasket at this, but their is a larger variance between BRANDS of brass, than their is between "regular" and "plus-P" brass. As far as strength goes (for either), dispite his rantings, you won't start lossening primer pockets until your in the 75-80,000 PSI range IOW well above what ANY cartridge is spec'ed at for max pressure.
Buddy of mine has pushed his 257AI to 25-06 velocities, and the "regular" brass has no problems handling it (note: this is not something you should try at home).0 -
I ran a 140gr a-max out of a 26" 1:8 twist PacNor in 6.5-06AI over the chrono at 3208fps[:0],..needless to say, primer pockets toasted on the first firing[V] The primers weren't even flat yet and the bolt wasn't sticky,...but that is a result of the Ackley case shape and reduced thrust.
Primers fall out because someone was too frugal to replace the cases when needed. Once my primers even begin to feel the least bit easy to seat, the cases are tossed. A pierced primer was someone hotrodding with a fast powder or a full boat load trying for every little last FPS they could get. Some chamberings actually shoot better at top loadings (PPC and BR to list a few) but their relatively small powder charges allow long case life.0 -
80,000psi without any primer problems? On ANY cartridge!! Ever heard of a 45 acp, 38spl, 44spl, 8mm mauser and the list goes on and on, this is crazy. I am not even sure you could get 80,000psi on some cases without going to a blank powder, But trying this would result in a real problem. This kind of pressure is way, way over proof pressures on many rounds. SAAMI makes allowances for primer leakage on proof rounds. This statement is based on what? A couple of guys you heard talking and could guess the pressure by the muzzle blast sound? Any cartridge!!! I guess some crazy posters will say, "yea that is correct, I use to shoot my old 30/06 a 130,000psi all the time, no primer problems on my end and I used mixed range brass I'd pick-up when I finished drinking my beer, and the best thing about the load, it way out did the 30/378-in fps, and I always shot .2MOA, took a lot of big ELK at 1500 yards with those loads, and never had a primer, case, or any other kind of problem." "Plus I load all my really good rounds on a progressive press, and set my dies with an RCBS whiz tool i got at a yard sale!" God bless them. 0 -
quote:Originally posted by idahoducker
Besides some guy having nothing to say about it in his book, what exactly is wrong with the RCBS mic? I did some research and found a lot of good user reviews.
I guess you could call Zediker "some guy", as you could David Tubb, they have done a book or two togeather. But yea if you haven't heard of them, they don't really count. But you are not alone, many on the thread have never heard of P.O.Ackley, and if they have, don't think much of his work, he just does not come up to their standards.0
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