Half full case = high pressure ?

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88 man

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I've got a newer Win 86 LW in 45-70.I loaded some shells up and tried her out.She kicks like a mule !!!
Would there be extra pressure caused by having the case about half full of power ?.I was told this could be why rifle kicks soo hard but I don't know.I loaded them light,about the second load up from bottom on my chart.Should I be using a filler to top it up ?
Any thoughts please !
Thanks
 
don't know what powder you are using ,I try to keep the case at 85% or more to prevent scarry incedents .I haven't used fillers so I can't comment on them .Some of the more experienced with this will probably be of more assistance ,but you may have to supply a bit more info Cheers
 
There are a great many different powders that work well in a 45-70.
Tell us your powder and load, then we can make a more accurate assessment of it.
 
If I can remember right load was IMR 4198 with 53.7 grs under a 300 gr HP.Using the bottom load on the chart.If I have to will pull a bullet and weight whats in it but pretty sure this is the load,it's been a while since I loaded them.
Thanks
 
I'm using 32gr IMR 4198 with 300-405gr bullets in my Falling Block rifles and they don't hurt to shoot. I would look at trap door rifle level .45-70 loads and work up from there for your gun.
 
88 man said:
If I can remember right load was IMR 4198 with 53.7 grs under a 300 gr HP.Using the bottom load on the chart.If I have to will pull a bullet and weight whats in it but pretty sure this is the load,it's been a while since I loaded them.
Thanks
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That is a mighty skookum load, no wonder it kicks!
In the Aug-Sept issue of Handloader there is a long article on actual testing of loads for the Marlin.
58 grains of H4198 is top of the loading for Marlin, with a 300 grain bullet, giving 35,000 cup of pressure and 2,444 fps velocity.
 
By the sounds of that I guess I'll be pulling bullets and a lighter load going in !.Hope I can save some bullets as I've got 50 loaded up.
Thanks !
 
55gr of H4198 under a 300gr JHP produces 2358fps out of my 24" barrel. Kicks like crazy.
57gr of H4895 under a 300gr JHP produces 1960fps out of the same. Kicks hard but manageable.
36gr of H4895 under a 500gr cast bullet produces 1312fps
16gr of Bluedot under a 500gr cast bullet is like a moose fart (didn't chrony it)

The myth of unfilled cases produces higher pressures than normal has been around a very long time. I have yet to see anyone who actually tests by measuring the pressure to either confirm or deny the myth. I have never run into high pressure signs on my cases from running 10-60% full cases without any buffer but that's just me. In fact my only issues with partially filled cases has been greatly reduced pressure so the powder doesn't even burn properly. I made up some .303 British loads using only 20gr of H4895 under a 150gr bullet and it fired, chrony gave an error on every shot, and there was loads of unburnt powder in my barrel after each shot that I needed to clean out.

Considering how many actual reloading books the "don't tumble loaded ammo" myth was in and again it has no proof supporting it but lots of people who have tried it with no problems I would say the high pressure from unfilled cases myth could go either way.

As for reloading pulled bullets there isn't much problem. Cheaper bullets can have the lead separate from the jacket from what I've read greatly reducing accuracy. I have tested new vs. pulled Berger 140gr VLD 6.5mm's in my M96 Swedish Mauser before because I just happened to have some. The new bullets are almost touching at 100yds and the pulled bullets grouped about 2".
 
LUTNIT said:
55gr of H4198 under a 300gr JHP produces 2358fps out of my 24" barrel. Kicks like crazy.
57gr of H4895 under a 300gr JHP produces 1960fps out of the same. Kicks hard but manageable.
36gr of H4895 under a 500gr cast bullet produces 1312fps
16gr of Bluedot under a 500gr cast bullet is like a moose fart (didn't chrony it)

The myth of unfilled cases produces higher pressures than normal has been around a very long time. I have yet to see anyone who actually tests by measuring the pressure to either confirm or deny the myth. I have never run into high pressure signs on my cases from running 10-60% full cases without any buffer but that's just me. In fact my only issues with partially filled cases has been greatly reduced pressure so the powder doesn't even burn properly. I made up some .303 British loads using only 20gr of H4895 under a 150gr bullet and it fired, chrony gave an error on every shot, and there was loads of unburnt powder in my barrel after each shot that I needed to clean out.

Considering how many actual reloading books the "don't tumble loaded ammo" myth was in and again it has no proof supporting it but lots of people who have tried it with no problems I would say the high pressure from unfilled cases myth could go either way.

As for reloading pulled bullets there isn't much problem. Cheaper bullets can have the lead separate from the jacket from what I've read greatly reducing accuracy. I have tested new vs. pulled Berger 140gr VLD 6.5mm's in my M96 Swedish Mauser before because I just happened to have some. The new bullets are almost touching at 100yds and the pulled bullets grouped about 2".
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Unless you are using a very slow power which you are not there is no issue having a lower volume of the case occupied. (and even then you would have to be at least 15% under max)

What you call a Myth (Secondary explosion effect) has to my knowledge only been reproduced in a lab by one company (Norma). You can try loading weak loads of slow powders all day and you will probably not have issues...or you may....Why take a chance...this is why there are start loads as well as max loads in your loading manual.
 
with low load densities and slower powders in a given cartridge, they tend to perform poorly. Can create significant pressure swings either way.

The powder shifts around differently everytime the each cartridge is fired. this tends to cause an inconsistant fluctuation in burn characteristics.

I have shot allot of cast bullets with faster powders. IMR SR4759 for example, is a powder that is reccommended for nearly every reduced loaded cartridge. When the reccommended charges are fired there is no problem. But, the accuracy can suck allot of the time.

When shooting cast bullts in my .308 target rifle, I noticed this trend with low density loads. To correct/minimize this variable, I started chambering each cartridge in a routine that allowed the powder to stay against the primer more consistantly. My accuracy INSTANTLY improved!

I then tried a DACRON filler on my next loads to keep the powder in place during normal handling and chambering. The accuracy improved dramatically.

I even tried a few loads that previously shot terrible to see what wold happen. Even the bad loads shot much better.

I believe that consistant powder position is very important even with jacketed and conventional loads. I have repeatably PROVED it to MYSELF through testing. Some case/powder/bullet combinations are less sensitive than others with this variable. Usually the straight wall cartridges seem to be more tolerant.

Hopefully I have both explained myself clearly, and given some useful information that can help someone.
 
LUTNIT, I'm with you on this one. There are more unproven theories floating around in the field of shooting in general and reloading in particular, than in any other field I can think of.
A long time ago I taught people to fly airplanes. When I was taking the instruction to have a instructors endoresment added to my commercial ticket, they taught something that I have never forgotten and have tried to apply it to all other situations in life.
They said to don't ever tell a student anything (theory) that you couldn't prove to him/her in the aircraft in flight.
In other words, when you tell the student something about flight, prove it right there in the cockpit!
If this were applied to reloading, most of the theories would disappear in front of our eyes.
Look how much has been witten on these threads about the completely unproven theory of barrel breakin.
Or, powder density in a cartridge case.
If a partial case of a certain powder is dangerous, then prove it. Rig up a safety release of the trigger and let's see you blow up a junk rifle with your theory. Prove it, or don't repeat it.
And dthunter, I have tried filler in cases ever since the popular material to use was corn starch. I've gone through stages where I considered a filler was better than no filler. I have made some great groups using a filler.
Then I found I couldn't duplicate them. Next time I did exactly the same thing, but got groups no better, or even worse, than my test loads of no filler.
Thus, there is no way that I could prove to myself that using a filler with light loads was any help.
 
88MAN:
I LOVE my Guide Gun, but it fires really big bullets. If you speed them up they'll hit ya back. Correct me if I'm wrong, but the old Springfields used to move a 500 grain bullet around 14 or 15 hundred f/s right? That gives it a Taylor Knockout value of "47". A 30-06 with a 180 at 2700 f/s has a knockout value of "21". I've hunted both of these calibers but I tend to "hot up" the 45/70 because of the flatter trajectory.
I use a 405 jacketed with 46.5 grains of RL7 and get just shy of 1700 f/s and a ragged hole three shot group at 50 yds! Do they kick a bit? Yes, but they work great. Just not what I would term a gallery load.
For every action there is an equal and opposite reaction.
 
H4831, I see what you mean, but I believe I can show you or ANYONE out there that I CAN duplicate that filler does make a "CAST Bullet" load more consistant( in the .308 Winchester cartridge). Thousands of rounds down range is the only proof that I need. Been there, done that, many times over. I have written records of all the tests I have completed in this reguard. I have shared allot of my findings here on gunnutz and a few other forums. I test my load variables that make positive changes at least 3-5 times on (different days) before I consider a load recipe/procedure change tried and true. Then I take out said loads, and prove thier performance over various ranges to see what they do. I have shot my cast bullet loads out to 500+yards. distances like that really test a cast bullet load. I love this shooting, and do allot of it.

I have spent more time doing load development for various firearms than I can count. I know that some people cant be convinced of anything that THEY dont experience it themselves. I know that with the help of NUMEROUS EXPERIENCED shooters, I have improved my cast shooting immensly! I thank those people, for I cannot live long enough to make all the mistakes myself.

Just so we are CLEAR, I never said that I could duplicate dangerous pressures created by low loading densities. I simply stated that very low density charges "Tend" to create inconsistant igniton characteristics, Therefore accuracy potential/consistancy. Less so in some cartridge designs and bullet combinations.

My experience with cast bullet shooting is with only 7-8 different calibers/cartridges. But I think thats enough of a cross section to get a good idea of whats going on.

I look forward to learning something new every time i shoot or talk to other shooters. Our INDIVIDUAL experiences are not always the same as other shooters. But when i offer personal information about shooting, its always been tried,tested, Repeatedly. Otherwise I indicate my experience definciency on a subject, and open myself to other shooters experience.
 
H4831 said:
.
If a partial case of a certain powder is dangerous, then prove it. Rig up a safety release of the trigger and let's see you blow up a junk rifle with your theory. Prove it, or don't repeat it.
Click to expand...

I wont' try to duplicate it. Like I said it probably wont' be willingly reproduced but seeing pictures of Baribal's gun after a light load of slow burning powder in his 6.5x55 makes me think that there is some truth to certain theories.
 
88 man said:
If I can remember right load was IMR 4198 with 53.7 grs under a 300 gr HP.Using the bottom load on the chart.If I have to will pull a bullet and weight whats in it but pretty sure this is the load,it's been a while since I loaded them.
Thanks
Click to expand...

Things can get dangerous that way. You should mark them with what and how much powder is in them and the date loaded along with bullet type. Being safe is paramount.
 
Well I dumped a couple shells and I loaded them with 54.3 grs of 4198.I was using the 4.3cc Lee powder cup.I guess they were a little hotter than I thought.I'll be going with a lighter load about the 40 gr mark so that should take away the
" kicks like a mule rifle " !. I should be around the 1900-2000 fps mark with the lighter load and still plenty enough power for any deer and no bruised shoulder !.
 
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