How important is a filled case

popeyespappy · October 31, 2010, 11:36 AM

I just got finished loading my first 50 rounds of 45-70. I’m trying some IMR-4198 and RL 7 (separately) under some cast 405 grain RNFP. I started with pretty low amounts of both and worked my way up 0.5 grains at a time with 3 rounds of each weight. But even at the high of what I loaded the cases weren’t even close to full. As in I can shake them and hear/feel the powder moving around.

My question is how important is a filled case going to be for consistency? I haven’t made it to the range with these yet but do I need to be thinking about another types of powder that will fill the cases better for my milder loads and save the 4198 and RL 7 for thumpers?

Rifleman1776 · October 31, 2010, 11:41 AM

You should be alright. Some small cases, like pistol, can be affected by a 'primer up or primer down condition' if too little powder is present. But a big, honkin' case like the 45-70 will require more than enough powder to avoid that. But with your test rounds do check for signs of excess pressure. If there is any excess pressure sign, go back to your reloading manual and see what it has to say.

HiBC · October 31, 2010, 12:46 PM

The 45-70 was designed for black powder.The case is sized appropriately for BP and the strength of rifles of the day.
If you are loading Black Powder at some time,you must fill the case all the way.even give it some compression.No air gap in the case!

Smokeless is a whole other ball game.

There are some strong rifles like the Ruger #1 that will allow you to use your case capacity,but older BP rifle designs present a handloading challenge:Selecting a powder that can work well at low pressures and provide sufficient bulk to work out well.

mikejonestkd · October 31, 2010, 12:46 PM

You'll be fine. Remember, the .45-70 was designed for 70 grains of black powder...and modern smokeless will give you similar pressures and velocities with much, much less powder...

for another example - My plinking loads in .357 ( 3.6 grains of 231 or 3.0 bullseye under a OTLC 158 grain flat point) barely seem to cover the bottom of the case...

flashhole · October 31, 2010, 01:03 PM

What kind of gun are you shooting? My 45-70 is the Marlin Guide Gun. My primary bullet is the Hornady 350 grain RN and my go-to powders are H4895, Varget, and IMR30-31. All provide a full case and all are very accurate in my gun.

popeyespappy · October 31, 2010, 02:02 PM

It’s a Guide Gun. Since this is my first time reloading for it I started out with light loads. Eventually I’ll probably work up to some heavier loads but for now I wanted to keep it on the mild side. My big question at this point is how consistent can I expect these loads to be when the case is only ¾ full? Can I expect to see large pressure variations and big SD numbers due to how the powder is laying in the case? If so I’ll start looking at bulkier powders for the light loads.

kraigwy · October 31, 2010, 02:59 PM

I use to shoot a lot of 4198 in 45-70 cases trying to keep the velocities to the same specs as the old government load. It was pretty good but left a lot of space that didn't help accuracy.

I tried Trail Boss, I found I can get the same velocity filling the case up about 75% to the base of the bullet. A whole new ball game, its consistent and more accurate.

flashhole · October 31, 2010, 03:08 PM

Don't know if this will be of use to you but you might check it out.

http://www.beartoothbullets.com/tech...h_notes.htm/49

When doing load development I seek out powders that provide good case fill. I get good accuracy in all my rifle loads so it certainly isn't hurting the situation. I can't offer any direct experience with loads that leave a lot of room in the case.

October 31, 2010, 12:46 PM	#4
mikejonestkd Senior Member Join Date: January 3, 2006 Location: Brockport, NY Posts: 3,717	You'll be fine. Remember, the .45-70 was designed for 70 grains of black powder...and modern smokeless will give you similar pressures and velocities with much, much less powder... for another example - My plinking loads in .357 ( 3.6 grains of 231 or 3.0 bullseye under a OTLC 158 grain flat point) barely seem to cover the bottom of the case... __________________ You are the bows from which your children as living arrows are sent forth. Last edited by mikejonestkd; October 31, 2010 at 04:01 PM. Reason: typo

October 31, 2010, 01:03 PM	#5
flashhole Senior Member Join Date: February 9, 2005 Location: Owego, NY Posts: 2,000	What kind of gun are you shooting? My 45-70 is the Marlin Guide Gun. My primary bullet is the Hornady 350 grain RN and my go-to powders are H4895, Varget, and IMR30-31. All provide a full case and all are very accurate in my gun. __________________ ,,, stupidity comes to some people very easily. 8/22/2017 my wife in a discussion about Liberals. Are you ready for civil war?

October 31, 2010, 02:59 PM	#7
kraigwy Senior Member Join Date: June 16, 2008 Location: Wyoming Posts: 11,061	I use to shoot a lot of 4198 in 45-70 cases trying to keep the velocities to the same specs as the old government load. It was pretty good but left a lot of space that didn't help accuracy. I tried Trail Boss, I found I can get the same velocity filling the case up about 75% to the base of the bullet. A whole new ball game, its consistent and more accurate. __________________ Kraig Stuart CPT USAR Ret USAMU Sniper School Distinguished Rifle Badge 1071

October 31, 2010, 03:08 PM	#8
flashhole Senior Member Join Date: February 9, 2005 Location: Owego, NY Posts: 2,000	Don't know if this will be of use to you but you might check it out. http://www.beartoothbullets.com/tech...h_notes.htm/49 When doing load development I seek out powders that provide good case fill. I get good accuracy in all my rifle loads so it certainly isn't hurting the situation. I can't offer any direct experience with loads that leave a lot of room in the case. __________________ ,,, stupidity comes to some people very easily. 8/22/2017 my wife in a discussion about Liberals. Are you ready for civil war?

October 31, 2010, 11:36 AM	#1
popeyespappy Senior Member Join Date: January 23, 2008 Posts: 337	How important is a filled case I just got finished loading my first 50 rounds of 45-70. I’m trying some IMR-4198 and RL 7 (separately) under some cast 405 grain RNFP. I started with pretty low amounts of both and worked my way up 0.5 grains at a time with 3 rounds of each weight. But even at the high of what I loaded the cases weren’t even close to full. As in I can shake them and hear/feel the powder moving around. My question is how important is a filled case going to be for consistency? I haven’t made it to the range with these yet but do I need to be thinking about another types of powder that will fill the cases better for my milder loads and save the 4198 and RL 7 for thumpers?

October 31, 2010, 11:41 AM	#2
Rifleman1776 Senior Member Join Date: April 25, 2010 Location: Arkansas Posts: 3,309	You should be alright. Some small cases, like pistol, can be affected by a 'primer up or primer down condition' if too little powder is present. But a big, honkin' case like the 45-70 will require more than enough powder to avoid that. But with your test rounds do check for signs of excess pressure. If there is any excess pressure sign, go back to your reloading manual and see what it has to say.

October 31, 2010, 12:46 PM	#3
HiBC Senior Member Join Date: November 13, 2006 Posts: 8,287	The 45-70 was designed for black powder.The case is sized appropriately for BP and the strength of rifles of the day. If you are loading Black Powder at some time,you must fill the case all the way.even give it some compression.No air gap in the case! Smokeless is a whole other ball game. There are some strong rifles like the Ruger #1 that will allow you to use your case capacity,but older BP rifle designs present a handloading challenge:Selecting a powder that can work well at low pressures and provide sufficient bulk to work out well.

October 31, 2010, 02:02 PM	#6
popeyespappy Senior Member Join Date: January 23, 2008 Posts: 337	It’s a Guide Gun. Since this is my first time reloading for it I started out with light loads. Eventually I’ll probably work up to some heavier loads but for now I wanted to keep it on the mild side. My big question at this point is how consistent can I expect these loads to be when the case is only ¾ full? Can I expect to see large pressure variations and big SD numbers due to how the powder is laying in the case? If so I’ll start looking at bulkier powders for the light loads.