Why the difference between RELOAD MANUALS?

MaineColt · March 23, 2008, 04:39 PM

I am loading .44 mag cartridges.
Loading Hornady 200 grain HP/XTP's.
Blue Dot powder.

Lyman manual lists the powder amount @ 15.7-18.7
Hornady manual @ 16.6-20.9

So, now that I've shot several rounds at 20 grains each, according to the Lyman manual I'm 1.3 grains over max.

I started at 16.0 grains and worked up 0.5 grains at a time, testing groups along the way. When I got to 20 grains, it was my most accurate by far. The more powder, the smaller the groups got. 16 gr. groups were at 4.5" at 25 yards. The 20 gr. group is 1 1/4".

BUT......before I load a couple hundred rounds at 20.0 grains each, I'm nervous that I'm overloading them.

Hornady manual was printed in 1980.
Lyman manual was printed in 2002.

Kev

freakshow10mm · March 23, 2008, 04:51 PM

Testing components and platforms is different.

One might use Winchester primers, the other Federal.

One might use a generic JHP bullet the other a specific brand.

One might use a "universal receiver" for testing, the other might use an actual firearm.

One might be located at 3000 ft above sea level, the other might be a 8000 ft above sea level.

One might load to a different OAL than the other one.

One might feel that a certain pressure is enough whereas the other might load a bit hotter.

**Unclenick** · March 23, 2008, 04:53 PM

Yeah, it's kind of a mess. Devil is in the details. Note that SAMMI only specifies external brass dimensions, so the manufacturers are free to do whatever they want on the inside, and sometimes that changes case capacity enough to affect pressure. Another detail is what gun you are shooting? Often, tough guns, like Ruger Revolvers or the Thompson Center single-shot guns, especially the beefy Encore, will safely handle much warmer loads than lighter guns.

So, double-check which components were used and that you are matching them.

Second, since the Hornady manual was published, the industry has gone over from mostly measuring pressure with copper crushers (C.U.P.) to using more accurate Piezo transducers (P.S.I.), and that has lead to changes in loads needed to meet SAMMI standards, which also were revised to match the newer system. You could well have seen some change because of that. Liability considerations also tend to reduce load recommendations over time, as the guns that use them get older.

Third, some manuals recommend load developed in actual production arms, while others do it in SAMMI spec test barrels. The latter have minimum size chambers and typically get to higher pressure with a given load than a production gun will. That is because the peak pressure you get to is dependent upon the volume the case expands to have in the chamber, not the volume of the sized case.

Search the forum for threads on pressure signs and learn them for your gun. Typically, though, a more accurate load is not a peak load for that gun. Most guns start to get less accurate as you go into excess pressure ranges because the metal is being distorted by the pressure. Your load is probably fine in your gun, but unless you say what it is, we can't advise you on that.

Gbro · March 23, 2008, 04:53 PM

The newer loading manuals seem to more conservative. That is why one should know the signs of pressure(over) and start low. Then the manuals will give data for their bullet, where lyman is more generic.

MaineColt · March 23, 2008, 04:55 PM

Freakshow10mm,

I hear you, but it still makes me nervous.

One used a standard receiver w/ 4" Bbl.
The other used a Ruger SRH, 7.5" Bbl.

Still a bit of a difference.

Kev

**Unclenick** · March 23, 2008, 04:58 PM

Ruger is stronger than average and will generally tolerate more pressure than SAMMI max. I presume that was the Hornady book's gun? In a revolver, if the cases eject easily and don't stick in the cylinder at all, you very unlikely to be at the gun's maximum pressure tolerance.

P.S. Just checked my own Lyman manual, and I guessed right. Doubt very much that you are in trouble there if you are also using a Ruger Redhawk?

P.P.S. The very confusion you are suffering is the reason for the common recommendation to own at least three loading manuals and to start working up from the lowest load given among the three.

P.P.P.S. It might interest you to know the CIP (Europe's equivalent of SAMMI) puts the .44 Mag safe peak pressure at 2800 bar, or 40,644 PSI, while SAMMI wants it down at 36,000 PSI. I believe the original developed cartridge spec for the .44 Mag was the same as the original for .357 Mag, which was something more like 42,000 PSI equivalent in CUP? Both seem to have been lowered over liability concerns.

MaineColt · March 23, 2008, 04:59 PM

UncleNick,

Shooting a Ruger Redhawk, Stainless, 5.5" Bbl.

Kev

MaineColt · March 23, 2008, 05:01 PM

Quote-UncleNick-"Ruger is stronger than average and will generally tolerate more pressure. I presume that was the Hornady book's gun?"

Yes, in the Hornady manual, it was the Ruger SRH.

Kev

MaineColt · March 23, 2008, 05:02 PM

No sticking of the cartridges at all using 20.0 grains of Blue Dot.

No sign what-so-ever of flattened primers either.

**Unclenick** · March 23, 2008, 05:19 PM

Those facts plus good accuracy all add up to you being in cool shape with that load. I also ran it in the QuickLOAD computer program, and making their straight case allowance to compensate the pressure calculation, I came up with 20.3 grains (full case of Blue Dot with no compressing of the powder) and the bullet seated to 1.610" COL, a pressure of 34,319 PSI. Lower than Lyman's CUP reading, but CUP and PSI don't track very well and jump back and forth as to which reads higher in the Magnum handgun range, so that suggests you are fine, too. I'm sure your cylinder chambers are bigger than their's was anyway.

MaineColt · March 23, 2008, 05:35 PM

thanks unclenick,
Yes, my OAL is indeed 1.610" as well.

I appreciate you checking on your program, thanks for everything. Going back to the reloading bench to finish up.

Kev

kraigster414 · March 23, 2008, 06:15 PM

From my experience as a reloader for 25 plus years, Lyman's loads have always been very conservative. Speer's loads on the other hand have been more daring, and Hornady's somewhere in the middle. I think liability has a lot to do with it.

freakshow10mm · March 23, 2008, 06:21 PM

The original 357 Mag's MAP was 50,000 psi.

Mr.RevolverGuy · March 23, 2008, 08:16 PM

All have given great advice here. I like to go with the manufacturer recommendations.

http://www.alliantpowder.com/reloade...27&bulletid=85

According to the link above 17 grains is max. I take 10% off that and then work my way up until I get what I need. Bluedot is a good powder for 44mag. I have found that HS6 is a bit more accurate for me.

I do find your results a bit strange because with me the heavier loads with bluedot were all over the place. The hotter I made them up to 18.2 grains the wider my group got. According to lyman 48th edition 18.7 is max. The accuracy problem was the reason I switched to HS-6. When switching to HS-6 I also switched to 240gr.

When I believe I will get the chance to hunt with my 44 I will load 10 rounds with h110 very accurate but very stout.

Speer 12th edition actually list 16grains of Bluedot as max.

Hornady 3rd edition list 20.9 grains as max. I would be afraid to go this high with Bluedot. Depending on the weather it can be temper-mental. If I needed to get 1500FPS which is what they list the max load as out of my 44 I will use h110.

March 23, 2008, 04:39 PM	#1
MaineColt Senior Member Join Date: November 2, 2007 Location: Maine Posts: 222	Why the difference between RELOAD MANUALS? I am loading .44 mag cartridges. Loading Hornady 200 grain HP/XTP's. Blue Dot powder. Lyman manual lists the powder amount @ 15.7-18.7 Hornady manual @ 16.6-20.9 So, now that I've shot several rounds at 20 grains each, according to the Lyman manual I'm 1.3 grains over max. I started at 16.0 grains and worked up 0.5 grains at a time, testing groups along the way. When I got to 20 grains, it was my most accurate by far. The more powder, the smaller the groups got. 16 gr. groups were at 4.5" at 25 yards. The 20 gr. group is 1 1/4". BUT......before I load a couple hundred rounds at 20.0 grains each, I'm nervous that I'm overloading them. Hornady manual was printed in 1980. Lyman manual was printed in 2002. Kev

March 23, 2008, 04:53 PM	#3
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	Yeah, it's kind of a mess. Devil is in the details. Note that SAMMI only specifies external brass dimensions, so the manufacturers are free to do whatever they want on the inside, and sometimes that changes case capacity enough to affect pressure. Another detail is what gun you are shooting? Often, tough guns, like Ruger Revolvers or the Thompson Center single-shot guns, especially the beefy Encore, will safely handle much warmer loads than lighter guns. So, double-check which components were used and that you are matching them. Second, since the Hornady manual was published, the industry has gone over from mostly measuring pressure with copper crushers (C.U.P.) to using more accurate Piezo transducers (P.S.I.), and that has lead to changes in loads needed to meet SAMMI standards, which also were revised to match the newer system. You could well have seen some change because of that. Liability considerations also tend to reduce load recommendations over time, as the guns that use them get older. Third, some manuals recommend load developed in actual production arms, while others do it in SAMMI spec test barrels. The latter have minimum size chambers and typically get to higher pressure with a given load than a production gun will. That is because the peak pressure you get to is dependent upon the volume the case expands to have in the chamber, not the volume of the sized case. Search the forum for threads on pressure signs and learn them for your gun. Typically, though, a more accurate load is not a peak load for that gun. Most guns start to get less accurate as you go into excess pressure ranges because the metal is being distorted by the pressure. Your load is probably fine in your gun, but unless you say what it is, we can't advise you on that. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

March 23, 2008, 04:53 PM	#4
Gbro Senior Member Join Date: February 20, 2005 Location: Minnesota Posts: 2,084	The newer loading manuals seem to more conservative. That is why one should know the signs of pressure(over) and start low. Then the manuals will give data for their bullet, where lyman is more generic. __________________ Gbro CGVS For the message of the Cross is foolishness to those who are perishing, But to us who are being saved, It Is The Power Of God. 1Corinthians 1-18

March 23, 2008, 04:58 PM	#6
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	Ruger is stronger than average and will generally tolerate more pressure than SAMMI max. I presume that was the Hornady book's gun? In a revolver, if the cases eject easily and don't stick in the cylinder at all, you very unlikely to be at the gun's maximum pressure tolerance. P.S. Just checked my own Lyman manual, and I guessed right. Doubt very much that you are in trouble there if you are also using a Ruger Redhawk? P.P.S. The very confusion you are suffering is the reason for the common recommendation to own at least three loading manuals and to start working up from the lowest load given among the three. P.P.P.S. It might interest you to know the CIP (Europe's equivalent of SAMMI) puts the .44 Mag safe peak pressure at 2800 bar, or 40,644 PSI, while SAMMI wants it down at 36,000 PSI. I believe the original developed cartridge spec for the .44 Mag was the same as the original for .357 Mag, which was something more like 42,000 PSI equivalent in CUP? Both seem to have been lowered over liability concerns. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle Last edited by Unclenick; March 23, 2008 at 05:11 PM. Reason: Added P.S. and P.P.S.

March 23, 2008, 05:19 PM	#10
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	Those facts plus good accuracy all add up to you being in cool shape with that load. I also ran it in the QuickLOAD computer program, and making their straight case allowance to compensate the pressure calculation, I came up with 20.3 grains (full case of Blue Dot with no compressing of the powder) and the bullet seated to 1.610" COL, a pressure of 34,319 PSI. Lower than Lyman's CUP reading, but CUP and PSI don't track very well and jump back and forth as to which reads higher in the Magnum handgun range, so that suggests you are fine, too. I'm sure your cylinder chambers are bigger than their's was anyway. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

March 23, 2008, 04:51 PM	#2
freakshow10mm Junior member Join Date: January 23, 2008 Location: MI Posts: 1,398	Testing components and platforms is different. One might use Winchester primers, the other Federal. One might use a generic JHP bullet the other a specific brand. One might use a "universal receiver" for testing, the other might use an actual firearm. One might be located at 3000 ft above sea level, the other might be a 8000 ft above sea level. One might load to a different OAL than the other one. One might feel that a certain pressure is enough whereas the other might load a bit hotter.

March 23, 2008, 04:55 PM	#5
MaineColt Senior Member Join Date: November 2, 2007 Location: Maine Posts: 222	Freakshow10mm, I hear you, but it still makes me nervous. One used a standard receiver w/ 4" Bbl. The other used a Ruger SRH, 7.5" Bbl. Still a bit of a difference. Kev

March 23, 2008, 04:59 PM	#7
MaineColt Senior Member Join Date: November 2, 2007 Location: Maine Posts: 222	UncleNick, Shooting a Ruger Redhawk, Stainless, 5.5" Bbl. Kev

March 23, 2008, 05:01 PM	#8
MaineColt Senior Member Join Date: November 2, 2007 Location: Maine Posts: 222	Quote-UncleNick-"Ruger is stronger than average and will generally tolerate more pressure. I presume that was the Hornady book's gun?" Yes, in the Hornady manual, it was the Ruger SRH. Kev

March 23, 2008, 05:02 PM	#9
MaineColt Senior Member Join Date: November 2, 2007 Location: Maine Posts: 222	No sticking of the cartridges at all using 20.0 grains of Blue Dot. No sign what-so-ever of flattened primers either.

March 23, 2008, 05:35 PM	#11
MaineColt Senior Member Join Date: November 2, 2007 Location: Maine Posts: 222	thanks unclenick, Yes, my OAL is indeed 1.610" as well. I appreciate you checking on your program, thanks for everything. Going back to the reloading bench to finish up. Kev

March 23, 2008, 06:15 PM	#12
kraigster414 Senior Member Join Date: March 17, 2005 Location: USA Posts: 114	From my experience as a reloader for 25 plus years, Lyman's loads have always been very conservative. Speer's loads on the other hand have been more daring, and Hornady's somewhere in the middle. I think liability has a lot to do with it.

March 23, 2008, 06:21 PM	#13
freakshow10mm Junior member Join Date: January 23, 2008 Location: MI Posts: 1,398	The original 357 Mag's MAP was 50,000 psi.

March 23, 2008, 08:16 PM	#14
Mr.RevolverGuy Senior Member Join Date: February 24, 2007 Location: Ohio Posts: 991	All have given great advice here. I like to go with the manufacturer recommendations. http://www.alliantpowder.com/reloade...27&bulletid=85 According to the link above 17 grains is max. I take 10% off that and then work my way up until I get what I need. Bluedot is a good powder for 44mag. I have found that HS6 is a bit more accurate for me. I do find your results a bit strange because with me the heavier loads with bluedot were all over the place. The hotter I made them up to 18.2 grains the wider my group got. According to lyman 48th edition 18.7 is max. The accuracy problem was the reason I switched to HS-6. When switching to HS-6 I also switched to 240gr. When I believe I will get the chance to hunt with my 44 I will load 10 rounds with h110 very accurate but very stout. Speer 12th edition actually list 16grains of Bluedot as max. Hornady 3rd edition list 20.9 grains as max. I would be afraid to go this high with Bluedot. Depending on the weather it can be temper-mental. If I needed to get 1500FPS which is what they list the max load as out of my 44 I will use h110.