Different Listed Max Charges from Equally Reputable Sources?

[DMW1116]

I am loading some 147 grain XTP bullets from Hornady for 9mm. I'm using HS-6 powder and CCI 500 primers. I checked the Hornady app for load data and it lists 5.3 grains as max, so I loaded them up for testing from 4.5 to 5.3.

This morning I decided to check another source, the Hodgden website. Lo and behold, they have a different max charge of 5.0 grains. This is with the same overall length. The only difference I can see is Hornady uses a WSP primer while Hodgden uses a CCI 500 like I did. Looks like I need to pull a few bullets and drop the powder charge. I also need to check my Lyman manual and see what it says too. Anyone have a reliable way to choose in a situation like this? If Hornady was all I had, I'd have just shot them and looked for pressure signs like usual. A man with a watch always knows the time. A man with 2 watches is never sure.

 

[Charlie98]

Hornady bullets... Hornady data. As long as you are matching their data for that bullet, you should be OK... but simply be observant as you work your way up the ladder. No data accommodates every combination of load, cartridge, and firearm... that's where the responsibility of the reloader comes in.

I will say, 147's in the 9mm is no joke... I got into trouble many years ago trying to load 147's to max... so, as I said, be observant.

 

[GeoDudeFlorida]

I am loading some 147 grain XTP bullets from Hornady for 9mm. I'm using HS-6 powder and CCI 500 primers. I checked the Hornady app for load data and it lists 5.3 grains as max, so I loaded them up for testing from 4.5 to 5.3.

This morning I decided to check another source, the Hodgden website. Lo and behold, they have a different max charge of 5.0 grains. This is with the same overall length. The only difference I can see is Hornady uses a WSP primer while Hodgden uses a CCI 500 like I did. Looks like I need to pull a few bullets and drop the powder charge. I also need to check my Lyman manual and see what it says too. Anyone have a reliable way to choose in a situation like this? If Hornady was all I had, I'd have just shot them and looked for pressure signs like usual. A man with a watch always knows the time. A man with 2 watches is never sure.

First, this:

I will say, 147's in the 9mm is no joke...

Second, a wise man once said:
Does anybody really know what time it is?
Does anybody really care?
If so I can't imagine why
We've all got time enough to cry

- Robert William Lamm, Chicago Transit Authority

 

[Hartkopf]

I would carefully test what you have loaded. HS-6 is a fairly predictable powder and you are using Hornady data so it shouldn't be a problem(if you did everything else right, like neck tension, COAL, etc)

What gun are you shooting these out of?

 

[Hartkopf]

BTW, I've seen the WIN primers run hotter than CCI, as in more 20fps faster on average. YMMV

 

[Kaldor]

I am loading some 147 grain XTP bullets from Hornady for 9mm. I'm using HS-6 powder and CCI 500 primers. I checked the Hornady app for load data and it lists 5.3 grains as max, so I loaded them up for testing from 4.5 to 5.3.

This morning I decided to check another source, the Hodgden website. Lo and behold, they have a different max charge of 5.0 grains. This is with the same overall length. The only difference I can see is Hornady uses a WSP primer while Hodgden uses a CCI 500 like I did. Looks like I need to pull a few bullets and drop the powder charge. I also need to check my Lyman manual and see what it says too. Anyone have a reliable way to choose in a situation like this? If Hornady was all I had, I'd have just shot them and looked for pressure signs like usual. A man with a watch always knows the time. A man with 2 watches is never sure.

Id send em over the chrono and see what you get. Realistically loading 147s much faster than about 1050fps is pretty tough, and is guaranteed to get you into trouble. So as you shoot them, just watch the velocity. Its also one of the reasons I prefer a faster burning powder like TiteGroup as it easily brings me up to that 1000fps threshold, with minimal pressure issues, with a very comfortable recoil impulse. HS-6 is a great powder, but I dont generally recommend it for heavy for caliber bullets.

Ive used Hodgdons data for years, and have never had a problem. Im honestly surprised that Hornadys data is actually higher, as their stuff seems to always be a little bit on the light side.

 

[jmr40]

Winchester primers tend to be a little hotter and that may, or may not mean a little more speed. I'd shoot a few and see how they do.

Seeing different max charges from different sources is common. You can see 50-100 fps difference in velocity with 2 different guns shooting ammo from the same box.

And sometimes one manufacturer simply stops testing at 5 gr. That doesn't necessarily mean 5 gr is the max safe load, that is just the max load they tested. A different manufacturer may stop at 5.3 gr and determine that 5.3 gr is still a safe load.

 

[fxvr5]

Hodgdon's 5.0 grain load for the 147 XTP shows a pressure of 27,900 CUP. The SAAMI max pressure limit is 33,000 CUP. The Hodgdon's 5.0 grain is far from maximum.

 

[DMW1116]

I plan to test them in a Canik Mete SFX with a 5.2” barrel. I noticed the pressure seemed low but I don’t know what the max is for 9mm so how low I couldn’t say. I’m going for maximum accuracy so a burning velocity isn’t required. I have not crimped them yet but typically run as light a crimp as my Lee FCD recommends.

 

[mdi]

An aside; I have never started a load using max. charges in any cartridge/gun. (reloading consistently 34 years, started in 1970 with a 6 year break) ..

 

[AJC1]

The rules don't change even if you have 100 different resources. The data in each manual or website were exactly those components in their controlled lab, most likely out of a test fixture.... this is a science where results are repeated over and over... be ware the exception and anomaly... most loaders build confidence in results with no data to substantiate their inclination. If your concerned about a number do you have a metric like a chronograph to compare your results to the previous test...

 

[film495]

the standard they use to determine max charge isn't necessarily the exact same. there's also always some difference in the test data they present that is different, chamber, trim length, bullet length, primer. a good reminder small changes can have bigger differences than expected. temp of the powder could change the performance. Maybe the lower max charge testers were in 100 degree weather, and the other test was done at 65. who knows.

 

[kalielkslayer]

I had a very similar issue with HS6 in 9mm, but with 124s.

I mentioned my load on THR. Somebody said it was below MINIMUM and cited his source.

I rechecked and the load was .3 grains below MAX with my source.

My second source showed it above minimum as well.

Bottom line is the various sources I use; Lyman, Hornady and Hogdgons regularly show variations in min, max and velocity.

In the instance above I was loading bulk ammo I wanted to function in 4 separate guns. I started at min, loaded 20. Walked outside and tried 5 in each gun. Then went up .1 grains repeat until the load consistently fed, ejected, locked back the slide. I never got near max.

 

[AJC1]

the standard they use to determine max charge isn't necessarily the exact same. there's also always some difference in the test data they present that is different, chamber, trim length, bullet length, primer. a good reminder small changes can have bigger differences than expected. temp of the powder could change the performance. Maybe the lower max charge testers were in 100 degree weather, and the other test was done at 65. who knows.

I believe i would be comfortable assuming all test data is done in a lab at 68-70 degrees and if your loads will be used above that, a reduction is prudent.

 

[higgite]

Note that Hodgdon shows 885 fps at 27,900 CUP at 5.0gr HS-6 while Hornady 7th shows 900 fps for the same load. That small difference in MV indicates to me that both sources are on the same page. I suspect Hornady pushed closer to SAAMI max of 33,000 CUP than Hodgdon did with their max load, resulting in 5.3gr at 950 fps. That being said, I don’t load to max, but if I did I wouldn’t be concerned with Hornady’s higher max while working up to it using typical load work up protocol. ymmv

 

[AJC1]

What are your concerns with the highlighted features? Bullet sized .357", Universal receiver, 4" barrel, groove diameter .356"?

Well considering most people are probably sizing 38 and 357 bullets to .358 and using an unknown frankenmixture of lead would be a good start.

 

[Varminterror]

Hodgdon's 5.0 grain load for the 147 XTP shows a pressure of 27,900 CUP. The SAAMI max pressure limit is 33,000 CUP. The Hodgdon's 5.0 grain is far from maximum.

This, FTW.

 

[Rule3]

Different data has been this way since the beginning of time, manuals and the internet.

It doesn't mean one or the other is wrong or bad. Just different tests by different people on different days. Both are within acceptable pressure standards even though Hornady doesn't list it exactly.

HS 6 is towards the slow end of pistol powders so .3 grains is not gonna make a whole lot of difference.

 

[fxvr5]

Well considering most people are probably sizing 38 and 357 bullets to .358 (so?) and using an unknown frankenmixture of lead would be a good start.

Not sure what you're saying.

 

[reddog81]

Not sure what you're saying.

The measuring fixture used by Lyman is unrealistic for use by anyone in the real world. The percent of people shooting bullets made of Linotype sized to .357 is so small It is probably less than 1% of the casting population.

The problem is that no 2 people are shooting the same alloy, out of the same gun, sized to the same diameter... Lyman's data along with all other manuals is a reference of what components they used and the results they got. Sometimes you can go below the starting data and get perfectly functioning ammo, sometimes you can go over the max data and get perfectly functioning ammo, other times you run into pressures issues before you even hit the max charge weights listed.

 

[AJC1]

I have only once found a load in a manual I thought was to hot. 8.8 grains of true blue with a 158 cast swc is the start charge, and I get the early signs of sticky extraction... I have zero desire to work up and my bullet is less than 158. Their data is in disarray but when hogden gets it all ironed out I'd like to see if it's changed.

 

[BBarn]

A 6% difference between Hornady and Hodgdon's data. Not unusual. Simply highlights the need to work up from starting loads.

As far as the Lyman cast data, it looks like Lyman used linotype because they were driving those 160gr cast loads at max pressure (which requires a hard alloy). Not sure why they sized to .357" except that perhaps that works well in combination with the hard alloy. Nor am I sure how Lyman could address the fact that many may load with a variety of alloys or an unknown alloy, short of testing with a range of alloys for every cartridge and bullet (which is unrealistic).

 

[GeoDudeFlorida]

A 6% difference between Hornady and Hodgdon's data. Not unusual. Simply highlights the need to work up from starting loads.

As far as the Lyman cast data, it looks like Lyman used linotype because they were driving those 160gr cast loads at max pressure (which requires a hard alloy). Not sure why they sized to .357" except that perhaps that works well in combination with the hard alloy. Nor am I sure how Lyman could address the fact that many may load with a variety of alloys or an unknown alloy, short of testing with a range of alloys for every cartridge and bullet (which is unrealistic).

It’s good data for reference though. The thing is if someone looks just at the load and velocity data, then tries to match it with a 60:1 lead cast bullet (about 8BHN) they’re going to be surprised at how different their results are from Lymans. It’s important to look at how the data was gathered, not just the tables of charges and pressures. Which has been a point some of us try to drive home every time the subject of “mismatched data” comes up.

 

[GeoDudeFlorida]

The measuring fixture used by Lyman is unrealistic for use by anyone in the real world. The percent of people shooting bullets made of Linotype sized to .357 is so small It is probably less than 1% of the casting population.

The problem is that no 2 people are shooting the same alloy, out of the same gun, sized to the same diameter... Lyman's data along with all other manuals is a reference of what components they used and the results they got. Sometimes you can go below the starting data and get perfectly functioning ammo, sometimes you can go over the max data and get perfectly functioning ammo, other times you run into pressures issues before you even hit the max charge weights listed.

Lyman’s started the switch to Linotype in the 46th edition (1982). The 46th mixed a lot of #2 Alloy and Linotype and has a couple of feature articles discussing crusher vs piezoelectric strain testing. That’s why it seems like Lymans data is inconsistent sometimes. You have to look at which testing process and materials were used.

 

[AJC1]

Lyman’s started the switch to Linotype in the 46th edition (1982). The 46th mixed a lot of #2 Alloy and Linotype and has a couple of feature articles discussing crusher vs piezoelectric strain testing. That’s why it seems like Lymans data is inconsistent sometimes. You have to look at which testing process and materials were used.

Based on lyno being basically gone, charts should be changed to Lyman #2. It's a much more reasonable standard based on current material availability.