Using primers as a sign in load development

[newton]

I have another thread going in the levergun section, but there does not seem to be much input over there. So I am hoping that someone over here, beyond the help I have already received(thank you), can give some input.

I am working up a load in a 30-30 lever action. I have reached max data for the same bullet weight but using jacketed data, for the powder I am using. I have gone over 2 grains max, and at that I am now at the velocity given for that max data on the jacketed bullet.

During this development I have been watching the cases very carefully. However, there are a LOT of people that say you wont see normal case/primer signs on lever guns as you do with bolt guns. I get that completely. But, there is one sign that some have said you can watch on a lever gun in regards to primers. That would be the primer backing out, or more correctly, not being reseated in the case due to "low" pressures. Not necessarily low as in not enough for the gun, but low as in just not enough to reseat. You guys that know this stuff know what I am talking about.

I know that there is some debate on how much pressure it takes exactly to reseat a primer, but a lot of that has to do with the chamber also. A rough chamber will not allow the case to flow backward as easily as a smooth chamber because the outward pressure grips the walls.


So the question is has anyone seen/known of too much pressure for a given case/round before the primer gets seated all the way back into the pocket? I know a lot of this is dependent on headspace, but lets say that the headspace is within spec for the gun. I am sure mine is. I will be measuring it though before I do any more development just to get a baseline.

[country gent]

Primers are used but its visual and alot of speculation opinion as to what is flat what is resetted and such. Also keep in mind the same primers are used in the old Lower pressure rounds and the new high pressure rounds. A primer showing pressure in a 30-30 desighned for 30,000 cup (est) may actually be slightly over pressure. While in a 300 win mag ( 60,000 cup) the same primer showing pressures may be a little light yet. Another way to judge pressures is to fire some factory loads and measure expansion just ahead of the rim. You want this to be a very accurate measurement to .0001 and then hold your handloads to this measurement. A new load showing .001 more expansion of the case head is probably on the warm side . You can judge loads subjectively by felt recoil extraction force needed primers case head expansion and or case life. Most ways for a handloader are some what subjective and depend on what each calles flatened, hard extraction, heavier recoil, ect ect. The case head measurement is repeatable.

[newton]

Thanks. I am starting to gather some good thoughts on my situation. Just helps to talk it out. I think I have gone past where I should have. I hope I have not done any damage to the rifle.

[country gent]

Questions and "talking it out" is how we learn. The knowledge is here for the asking you just need to bring the container. I doubt you have seriously damaged the rifle so far. Keep in mind most proof loads were are in the 80,000+ cup range A steady diet isnt recomended but 1 dosnt change much. Lymans manuals have good information on reading pressures also, as do most reloading manuals. Heres something to thinkl about I once was at a high power rifle match and the guy next to me rifle was ( AR in 223) was sounding diffrent. In the pits we were chatting and he said he was barley flatening primers. After 600 I picked up a couple of his cases and the whole radious on the primer cup was gone, his idea of slightly flattened primers. Also keep in mind a safe load in 30* temps may exhibit be over pressure in 90* temps. Ambient temperatures ammo temp affect pressures also.

[newton]

Yea, I think I brought too big of a container with my other post and it scared people off from dumping into it. lol

I shot a total of 5 round over the max for the jacketed load I was using data from. From all indications, only the last one was getting close to being the high pressure of the bunch. Also, if you look at hogdon data, and somewhat follow what they have listed for powder choice I am using, you could almost say that my top load is approaching the 42,000 psi mark.

I am not trying to reach that at all. I was trying to get to a certain fps, just for the fact of trajectory. But I have run the numbers again and realize its just a few inches at the longest distance I'd be shooting. One thing that did not stick well enough until today is the fact that most published data is for 24" barrels. Mine is a 20" barrel. While there is some differences on how much fps you loose per inch, the average I have found is right around 25. So that would be 100 fps less. If that's the case, then I am not too far off the published load data for that jacketed round.

So I'll be not going to the upper limit again for sure. I'll load back down and adjust my sights accordingly.

From everything I can dig up, the lever action 30-30 is almost the worst gun to try and judge pressures in. Go figure.

But I still think there is something to be said, even if its just a little, about not reading the flattening or pin strike, but reading the primer distance away from the case rim. I just cannot see how the case would not fully retract toward the bolt face, thereby reseating the primer completely(but not necessarily flattening it), before it blew the chamber apart. I could see how the primer would not get flattened, but I guarantee that I do not put more than 42,000 psi on my primers to seat them. And even though there is more at work than just 42,000+ psi pushing rearward(because its actually pushing to the sides more than backward), when you get too high then the sides will for sure not hold it from going backward.

I still need to shoot some factory ammo and get a base line. And I think that if I were going to work up in a manner like this again I would want to make sure my chamber is very clean.

Its helped a lot doing all of this searching because I know a lot more now about the way a case acts in the chamber.

[osteodoc08]

There have been several articles in reloader magazine describing case head expansion as a "reliable" way to develop loadings. This compares factory CHE with what you're getting. I'd recommend reading up on this. Using primers as a pressure tell tale, while useful, if frequently misread and/or unreliable due to too many factors. A chronograph is also helpful. As is quick loads.

ive found that using book data has allowed me to keep my vision and digits while allowing me to accomplish the task at hand. I've never seen a dead deer complain of the velocity in which it was hit. Even a moderate load out of a big bore wheelgun will suffice for all game in the lower 48 assuming the Hunter does their job.

[newton]

There have been several articles in reloader magazine describing case head expansion as a "reliable" way to develop loadings. This compares factory CHE with what you're getting. I'd recommend reading up on this. Using primers as a pressure tell tale, while useful, if frequently misread and/or unreliable due to too many factors. A chronograph is also helpful. As is quick loads.

ive found that using book data has allowed me to keep my vision and digits while allowing me to accomplish the task at hand. I've never seen a dead deer complain of the velocity in which it was hit. Even a moderate load out of a big bore wheelgun will suffice for all game in the lower 48 assuming the Hunter does their job.

I have read up on that. Just need to get me some new cases to test with is all now. Hogdon even has an article write up on it. It should be anywhere from .0003" - .0004".

http://www.hodgdonreloading.com/reloading-education/tips-and-tricks/simple-trick-monitoring-pressure-your-rifle-reloads

While I was not looking for velocity for the dead deer effect, I was more looking for it for the trajectory effect. I do, however, want something more than .22 lr velocity. I am not searching for speed, but using it as a tool for looking at what book numbers say. I will do more testing, but I believe the load I settle in on will be right around 1800 fps, which is fine for me with the boolit I am using.

Simple fact is that there is not much book data on what I am trying to do. None in fact, I am having to base it off of what others have done(and lived to tell) and what the book says is like what I am doing.

One question this all brings up is when book data started using pressure tests for loads? How did they measure pressure back when they started using smokeless powder? Or did they use other means to develop loads?

[williamwaco]

I have read up on that. Just need to get me some new cases to test with is all now. Hogdon even has an article write up on it. It should be anywhere from .0003" - .0004".

http://www.hodgdonreloading.com/reloading-education/tips-and-tricks/simple-trick-monitoring-pressure-your-rifle-reloads

While I was not looking for velocity for the dead deer effect, I was more looking for it for the trajectory effect. I do, however, want something more than .22 lr velocity. I am not searching for speed, but using it as a tool for looking at what book numbers say. I will do more testing, but I believe the load I settle in on will be right around 1800 fps, which is fine for me with the boolit I am using.

Simple fact is that there is not much book data on what I am trying to do. None in fact, I am having to base it off of what others have done(and lived to tell) and what the book says is like what I am doing.

One question this all brings up is when book data started using pressure tests for loads? How did they measure pressure back when they started using smokeless powder? Or did they use other means to develop loads?

That is interesting and probably a good practice. NOTE they are talking about measuring NEW cases only after the first firing.

I have always made it a rule that any measurable expansion is too much but I have very rarely loaded or fired new cases.

[nekshot]

I totally understand your reason for seeking a better tomorrow! I am sure you didn't harm the gun if you were able to eject the cartridge. With the 30-30 and like for flatter shooting go with lighter bullets like the speer 130's. I took 150 gr nosler's and cut the nose off for a wide meplat and at a wt of 135 gr those babies would open up nicely at 30-30 speed. I personally don't trust my cast boolits beyond 150 yards simply because I am ignorant(lacking expierience) with them at that distance. While most of my hunting is under 50 yards the cast is fine but if I need a 175 yard shot I put a 130 jacket loaded for bear in the chamber.

[nekshot]

another reality, when you get a lever really shooting hot(heavy recoil) the mag tube and other attachments to barrel start coming loose. Thats why the levers that I load hot all have better dovetails for the mag tube and such.

[newton]

That is interesting and probably a good practice. NOTE they are talking about measuring NEW cases only after the first firing.

I have always made it a rule that any measurable expansion is too much but I have very rarely loaded or fired new cases.

I think it would be good practice if you were one to experiment for sure. It wouldn't hurt to have some new brass around just for this type of thing. I'll shoot a factory round first, measure the difference, then shoot one of my loads. In the end, it is probably a lot better practice that looking to primers for pressure signs.

[newton]

another reality, when you get a lever really shooting hot(heavy recoil) the mag tube and other attachments to barrel start coming loose. Thats why the levers that I load hot all have better dovetails for the mag tube and such.

I'll keep that in mind. I just want to shoot this heavy boolit is all, and do it at a modest velocity. I really, really wanted to get it up over 1900 fps, but I just don't think my 20" barrel is gonna do it with the pressures staying good. If I had a 24" barrel I think I could do it easy with this powder.

I know I have read about a guy on here, cant get a hold of him though, who uses this powder and boolit and says he gets over 2000 fps. But I am not sure if he mentioned what length his barrel is. I know he listed his load as being where I am going to stop at, but I was over his load before I reached 1900 fps. I bet he has a 26" barrel.

[country gent]

If you have a ballistics program to crunch numbers into ( Sierras infinity is very good ) and want a real eye opener punch in your existing load with bullets ballistic coeffient and information. Do this for a zero at 600 yds no start adjusting just the velocity to get a 6" change ( one minute of angle) You will be surprised how much it takes to get that change. Load for accuracy and teach your onboard computer ( brain) to estimate range accuratly and know drop/hold over. Shoot at diffrent ranges expected and prove what it takes to hit and adjust for wind.In other words with an accyrate load learn the rifles performance. Always remeber beware the man with one gun.

[newton]

If you have a ballistics program to crunch numbers into ( Sierras infinity is very good ) and want a real eye opener punch in your existing load with bullets ballistic coeffient and information. Do this for a zero at 600 yds no start adjusting just the velocity to get a 6" change ( one minute of angle) You will be surprised how much it takes to get that change. Load for accuracy and teach your onboard computer ( brain) to estimate range accuratly and know drop/hold over. Shoot at diffrent ranges expected and prove what it takes to hit and adjust for wind.In other words with an accyrate load learn the rifles performance. Always remeber beware the man with one gun.

Yea, the calculator I use doesn't allow that far. It tops out just under 4400 fps, which is a far cry from just a 6" change.

I will be happy with my 1800 fps I am sure. Like I said on another thread, I am not trying to squeeze the last bit of velocity from this round, just wanting to be the best it can be safely. The recoil is not bad at all, but I do not want to just poke a .308" hole in a deer also. I would like to know its going to expand, and exit at the same time.

I do not think that would happen with a 1200 or 1300 fps round. But I am not sure where I should get it too either. All the data I have found with people who love to shoot this boolit is where they are running around 1900 fps. So that's the only reason I set that as my goal.

[newton]

I just had a thought. Maybe I should focus my energy toward actually testing the boolit in some sort of medium to replicate flesh and bone. Then I could see whether or not it would be fine.

My maximum with my gun is 150 yards. I just do not think I will ever shoot at anything over that. But I have shot at, and hit, deer at 125 yards. I have a rear peep that lets me zero in pretty well.

[country gent]

Ill bet the diffrence between 1300 fps and 1800 fps with your bullet isnt a full 6-7" change at even 600 yds. Though it will make a diffrence in wind. Finding a reliable test medium that is useable at distances and allows for easy handling is an issue. Moving heavy block of ballistics gelatin, clay, wet phone books, and most test mediums becomes a real chore. Testing close dosnt give a true indication at how the load ullet will perform at full rangeand just at full range testing dosnt give upclose results. A lead alloy may perform diffrently up close at full velocity than it does at range and slowing down. Testing is good and you can learn alot if done correctly.

[303Guy]

U use primers to gauge relative pressure by reading the radius of the primer indent. It's a bit difficult to actually measure anything that small but I photograph the primer up real close then display it on the the computer screen and measure from that. I have found the indent diameter for a blanc case relative to the diameter and work out a ratio - taking out the firing pin diameter. I do it on spread sheet with the calculation embedded.

For bullet testing I found a fairly good test medium in the form of wool furniture padding compressed into a container and saturated with water which requires firing straight down into it. Therein lies the problem. I do have a suitable device for this type of testing which I call my 'test tube'. Now I use ground rubber tyres (with the fibre sieved out). I feel the rubber grounds should be packed tightly and contained radially by a strong tube. That can be mounted horizontally using rag to plug then entry (or a rubber diaphragm).

[John Boy]

Two additional factors can effect load pressure:
* An oversize diameter bullet
* A heavy case crimp
Put both together and there will be a spike in the reload pressure effecting the movement of the primer

[newton]

Thanks guys. Interesting info here. I watched the indent real close on the loads. It started getting crisper around the edges, but never real crisp.

With all I have read it takes more pressure than I should be getting to in order to mess the primers much. I have yet to find any photos from lever action 30-30 with primer signs of flattened or cratered.

[Larry Gibson]

P. O. Ackley's book contains an excellent chapter on using the primers backing out in 30-30 cases as a method of loading to maximum safe psi. He explains it very well.

The C.U.P. and L.U.P. methods of measuring cartridge psi was developed and available in the beginning of smokeless powder cartridge development.

Larry Gibson

[newton]

P. O. Ackley's book contains an excellent chapter on using the primers backing out in 30-30 cases as a method of loading to maximum safe psi. He explains it very well.

The C.U.P. and L.U.P. methods of measuring cartridge psi was developed and available in the beginning of smokeless powder cartridge development.

Larry Gibson

is that the name of the book? Any online source to read about it? Thanks

[gray wolf]

It sounds like you have a Chronograph,
but from your post I might question that, do you ?

Also I may have missed it-- but -- what bullet are you using ? what weight ?

The Lyman book shows shows at least 9 loads with a 150 grain lead bullet at 2000 FPS and faster and that is with a 24" barrel. Also at least 7 loads for a 170 grain bullet that go over 2000 FPS with a 24" barrel. Also about 9 loads well over 2000 fps with a 170 grain bullet. You should be able to do at least 1800 with a 150 grain bullet and your 20" tube. I would think that would be a pass through shot at a reasonable range.

Are you limited with powder selection or bullet choice ?
or am I just missing something ?

Watching for primers not to re-seat is not what I would be looking for while testing loads that are anything even near max. Unless your rifle is not in spec the primers should seat even with a minimum load.

Book FPS and chamber pressure is what they recorded, yours while probably safe most likely will be different.

I would not load any bullet 2 grains over anything without knowing how to read pressure so as to stay on the safe side. Your questions indicate you do not.

A Lighter bullet would greatly improve your FPS--I really don't think going over book on the powder is the beat approach or even having to worry about the fact that you may be in a danger zone. You keep saying how you don't want to hot rod the bullet powder combo -- but it seems you are.

Please be safe and don't take what I said as a slam --cause it's not.
Or perhaps like I said, I may have missed something.

[newton]

Gray Wolf, you have not missed anything on this thread I don't think. I have a couple other threads going that deal with the situation as a whole, but I was trying to break it down into specific questions I had instead of lumping them all together. I guess each way has its ups and downs when trying to get input.

My boolits are 194 grains. I am limiting myself with the boolit, because I want to shoot this particular one. Powder is not limited by my choice, but by availability. I was watching a myriad of things when working up my loads, I did not start at max and go higher above it immediately. Research lead me to the question at hand because of the fact that low pressure rounds will indeed not reseat a primer. This happens in bolt, lever, and single shot guns. The pressure presses the cases against the walls of the chamber, which if not completely slick(most factory guns have tooling marks), does not allow the case to also move backwards. All guns have a certain amount of head space, and this is the amount the primer can back out. Full pressure rounds overcome the case to chamber wall grab and move backward seating the primer back into the pocket.

I know this happens. I have witnessed it on several guns I have. That's the thing about shooting cast boolits. I have worked on all aspects of the pressure scale, except for the real high end. I have only worked on high end pressure scales with a .243 and jacketed bullets. It was only in that gun that I observed the primer flattening and cratering.

So, that's why I bring this up about the 30-30. Many people say that the pressures are just too low for you to have indications from it. But some say you can see some indication, if you are watching closely. I know how to read pressures, but wanted to see others thoughts on it who have gone before me in working up loads that are not listed. I know there are a few on here that do such things.

I do not want a hot rod bullet. I would think that a hot rod bullet would be trying to push my combo to 2100-2200 fps. I just want a good heavy round is all. 1900+ fps with this bullet is not hot rodding by any means and what most people look to get for hunting rounds.

I have thick skin, im not sure what it would take for me to get offended, but I assure you it would take a lot. You are no where near that level. :D

[newton]

yes, I have a chronograph and it is the main reason I have all these questions. I tested my rounds, and was not getting anywhere near what I would have thought I would be getting, based on many things, but most importantly others direct testing with the combo I am using. The only difference, which has been making me look at this differently, is the barrel length. I think that is the cause of some of my confusion, albeit not all.

[gray wolf]

Happy over here that my post didn't upset you, I see that you have some other post going also.

Sometimes this old internet differs quite a lot from the old fashion face to face chat.

[newton]

ya, I wish there was a meeting place around here that I could stop by after work and talk with guys. Most guys in my neck of the woods are still wrapped up in the black rifle debacle. I know there are some casters, but not many that I know of.

Internet makes it easy to reach a bunch of people at once though. Everyone just has to make sure that sarcasm, or the lack of it, is very very hard to interpret from folks. I do think, over time, you can start to see how ones punctuation and word choice give indication of their demeanor.

I always give people the benefit of the doubt at first. Then after multiple, blatant, direct insults will I feel offended. Usually guys will sneak one in, just to get their digs in, makes them feel good about theirselves. lol. I know I have done it. I just let that kind of stuff blow by. Everyone is human.

[newton]

Ok, so I had an opifany. I was reading an old hornady load book and the primer thing concerning head space hit me like a brick. I really believe that primer setback is mainly caused in non rimmed cases. Rimmed cases with excessive head space generally manifest theirselves with inconsistent primer strikes. Think about it for a minute. Headspace on a rimmed case is from the chamber face to bolt face, but a rimless case it's from the shoulder datum to bolt face.

From hornady book (paraphrased, but accurate) - rimless - pin strikes, case is pushed way forward into(key word) the chamber, pressure presses the case against the chamber walls somewhat preventing the case from moving back but the head does, case head stretches but only so far as the web allows, which in turn weakens that particular area, the primer has room to continue back and the stretch of the case is not enough to reseat.

Now rimmed cases - pin strikes, case is only pushed against bolt face, case expands against chamber, any excess space the head moves rearward, so on and so forth.

Difference is that the head space in the second can only become too large before the pin will not strike the primer hard enough. That's not so much true in the rimless cases. Only if the bolt is not closing enough does that happen. But you have the whole chamber and shoulder area that can be out of spec. The shoulder is the only thing holding the case from moving forward unlike the thick rim of a rimmed case.

So, I really think that primers sticking out of rimmed cases are good signs of under pressure. Unless, and this would be one sign, the pin strike is very weak on the primer with a rimmed case. That would indicate the case is sitting far away from the bolt face. The pin can only be so long to ensure it does not pierce the primer.

Whats your take on this?

[newton]

I can see some flaws, but it also makes some sense. Still not something I would put down as an absolute sign, but it would help me make some observations.

[TXGunNut]

My approach to 30-30 loads includes two basic assumptions; primers lie and the 30-30 is no hotrod. Primers and chambers vary and it's quite likely the 30-30 will be waay overpressure before the primer gives so much as a clue. Yes, the 30-30 was a high-velocity wonder in 1895 but today it just won't keep up with the big boys and quite honestly it doesn't need to. A chronograph is a much better tool than a primer dent, IMHO.