Chuck said
OK, I have some time between my wife's plans for me today.
Here is a page from the Ideal #15 catalog on page 130.  
Please read the second paragraph.  Dupont says to use filler. 
We have to remember this data was accurate at this time.  It does not mention the 40% rule of thumb or 4198.  Nor the fact that the modern equivalents produce more pressure at the old equivalent charge a lot of the time. It also says not to compress the load like I did the last firing.
  

Chuck,

That second paragraph does not say to use a filler... reread it carefully!  It very clearly states;

"the proper charge should be used and the air space left unfilled"

Bert

IMR 4198 is generally considered not position sensitive for most rifle cartridges, including common straight-walled black powder cartridges like the .45-70, .40-70 Ballard, and .40-90 Ballard. This means that, within normal loading density and pressure limits, you don’t need to worry about the exact placement of the powder in the case for consistent ignition and performance.

Why it’s not position sensitive

• Burn rate and formulation: IMR 4198 is a fast-burning extruded rifle powder designed for consistent combustion when loaded within its published pressure range.
• Experience in older cartridges: Reloaders using it in .45-70 and similar straight-walled cartridges have reported no issues with vertical stringing or erratic ignition when powder placement varies.

You are back to the "apples vs. oranges".  Dupont did not introduce IMR 4198 powder until the 1930s.  The "IMR" powders replaced the older No. 1 and No. powders because they were "Improved".  While the older No. 1 and No. 2 powders undoubtedly needed fillers, the more advanced (modern) IMR powders do not when loaded properly.  I am of the opinion that you are creating excessive pressure by using a filler to pack the IMR powder into the base of the cartridge.

Bert

Here is a page from the Ideal #15 catalog on page 130.  

Please read the second paragraph.  Dupont says to use filler. 

We have to remember this data was accurate at this time.  It does not mention the 40% rule of thumb or 4198.  Nor the fact that the modern equivalents produce more pressure at the old equivalent charge a lot of the time. It also says not to compress the load like I did the last firing.

Chuck said
I ordered 3 Ideal catalogs from Cornell Publications.  I received these last night.  Not only pictures and info on the mold but some other info I will post later.
Clarence told me a couple years back that I should buy the early 1900's Ideal catalogs when looking for the early smokeless loads. 
  

Good idea.  I have a couple of the older Lyman Ideal handbooks, but none that are just Ideal (pre-1925). What specific year catalogs did you acquire?

Bert

Clarence told me a couple years back that I should buy the early 1900's Ideal catalogs when looking for the early smokeless loads. 

I am going to redo the 30 grains loads and go up by .5 grain jumps. I am also going to think about my filler procedure.  I may have packed these too much trying to get the wad in. 

So here is the data for the 5 shots.  The first pic shows shot 5 data and the next pic shows the Summary of the five.

Sorry, the breach block was very hard to open and it took excessive pressure to move the lever.  Primers backed out and cases got stuck.  It only did this when the pressure got too high.  When I lowered the powder charge the problems went away.  This is all spelled out in the Forum posts for the 38 EX. 

Another post with a lot of opinion and nothing to back it up.. Most every time I post I will add pictures or the book and page that I reference.  Some of what you say I have given you the answers before.  No pictures no proof, isn't that what we say?  No references, no proof.

Show us the proof.

Chuck said
Not only hard bolt lift and a primer that backed out some, I had to use a cleaning rod to get the case out.  All clear signs of over pressure.  The headspace for most Winchester rifles is .007".  So even a highwall can have a primer come back that far.
I have been using fillers for at least 30 years.  Theory and assumptions are one thing but facts are facts.   I've quoted several times the Authors who say to use fillers.  I also have quoted the Authors who have documented an explosion that was caused by flash over.  You are ignoring the facts. 
Currently I just put a thin wad made to go over black powder and then a 1/4" thick piece of cotton to make sure the powder stays by the primer.   We will see what happens tomorrow.  Base upon the facts I will make adjustments as needed.
  

Show me proof of any flash over explosion that has ever occurred with IMR 4198 using a correct (published) load.  Frankly, it is you that is ignoring the facts... not every type of gun powder is the same.  While there are undoubtedly some types of powder that do need a filler to correctly ignite and burn properly, not all powders do, and IMR 4198 is in that category.  Bullseye and Unique are two more examples of powders that do not require fillers.  Both are low case volume powders that do not need filler material.  I know that I am probably talking to a brick wall, but I have 45+ years of experience loading with IMR 4198 and I have shot at least several thousand rounds of cartridges loaded with it... never with a filler, and never with any of the issues you are describing.

There is no "bolt" on a Single Shot high-wall rifle.  Further, due to the 5-degree angle orientation of the breech block, it cannot bind unless the head space is out of spec.  That is one of the better features of Browning's superb design.  If you are experiencing binding of the breech block, you have some other issue (problem) with the internals of the action.

I am way more inclined to go with what the powder manufacturer has published about their product than what some so-called "author" has published his opinion about in a book.

Bert

I have been using fillers for at least 30 years.  Theory and assumptions are one thing but facts are facts.   I've quoted several times the Authors who say to use fillers.  I also have quoted the Authors who have documented an explosion that was caused by flash over.  You are ignoring the facts. 

Currently I just put a thin wad made to go over black powder and then a 1/4" thick piece of cotton to make sure the powder stays by the primer.   We will see what happens tomorrow.  Base upon the facts I will make adjustments as needed.

Chuck said
I went back and looked at what happened with the 38 EX.  The factory BP load shot at 1,595 fps.  Barnes said to use 21 grs. of 4198 for 1,350 fps. or 23 grs. for 1,470 fps.  23 grs. at 1,400 fps. got me hard bolt lift and primers that were backing out.  I settled on 22.25 grs.  40% is 36 grs.  That is 13 grs. over where I experienced pressure issues. 
  

Chuck... "hard bolt lift" ???  I have never seen a primer back out on an original Single Shot cartridge with proper head spacing... it is physically impossible for the primer to move out of the pocket by more than a few thousandths against the breech block.

I am of the belief that the reason you may be seeing the issues you are experiencing is because you are using filler material on top of the powder.  As I have mentioned (several times), IMR 4198 is not position sensitive, and in all of the many hundreds of cartridges I have loaded with it, not once have I ever used a filler or wad to keep the powder piled up against the base of the cartridge.  Dupont never recommended using a wad or filler with 4198 powder.  By doing so, you are adding an unknown variable that changes the dynamics of the cartridge.

Bert

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