Questions about H110

[scottyp99]

Hi guys! I just received my order of 100 projectiles from Cast Performance (They're the 357 magnum 180 grain gas-checked wide flat nose) Anyway, I did a little playing around and measuring, and it seems that when I fill a once-fired, sized Starline case with H110 up to the level of the bottom of the boolit, the charge weighs 17 grains. So, a 90% full case would be 15.3 grains. The largest max charge weight I can find is 14 grains which is about 83% case fill. I was under the impression that H110 worked best above 90% case fill, so...what gives? My plan is to stay within published data, but still, I'm curious about this.

Scotty

[shootinfox2]

Please check your data. hogdon list 13.5 max in both rifle and pistol for 180 grain jacketed bullet. They did not list your cast bullet.

[bdicki]

http://www.handloads.com/loaddata/default.asp?Caliber=357%20Magnum&Weight=All&type=Handgun

[rancher1913]

do not worry with the percent of fill, just find a known recipe for your boolit and start with the minimum and ladder up to the max to see which one your gun likes best. h110 was the first powder I ever loaded with and it was also in the 357 magnum. don't over complicate things at first.

[Motor]

I've heard a lot of so called rules about H-110 and it's twin sister powder W-296 but I've never seen this "90%" thing, not ever.

A lot has been learned about H-110/W-296 as well as other ball powder(s) since these old rules were written.
I haven't loaded any 180gr but have been using 158gr JHP and cast for some time with a maximum load of 16.8gr Some newer data is even less so 17gr with any 180 is way too much.

I suggest you start at the jacketed data start loads and carefully work up if you want to work up.Watch for lead fouling and excessive pressure signs like sticky extraction.

Forget about all the percentage rules and use current trusted published data.

Motor

[dragon813gt]

There is no case fill rule. You either use a published start load. Or if there is only a max charge listed you start 3% below it. This number has changed over the years. 3% was what used to be listed on their online data center. The fact that they took it down and it can't be found has always bothered me. Their disclaimers for a lot of powders went away when they switched to the current format.

[waco]

H110/W296 DOES NOT LIKE AIR SPACE........just saying.......

[reddog81]

I've never heard of the 90% case fill rule. Where did that come from?

Just follow the load data.

[runfiverun]

it come from the powder not burning properly causing start/stop/start conditions.
H-110 is more dangerous in an under load situation than an over load situation when it nearly fills the case.

[scottyp99]

Well, see, that's the thing. People say H110/W296 likes a full case, but the load data I'm seeing isn't even close to a full case. What's up with that?

Scotty

[runfiverun]

I think it has to do more with actual bullet design than the weight.
many bullets out there have long noses to give you more room for more powder, others have an elongated nose but take up more case volume [the XTP design is famous for this]

[Lloyd Smale]

stick to the loads in loading manuals. Buy yourself a couple manuals and compare charge weights and don't go over the heaviest charge weight between all your manuals and don't go lower then the heaviest charge weight at the bottom end of the load data and you will be safe. Yes load manuals especially newer ones are a bit conservative but bottom line is a 100 more fps in a handgun isn't buying you much.

[dragon813gt]

Well, see, that's the thing. People say H110/W296 likes a full case, but the load data I'm seeing isn't even close to a full case. What's up with that?

Scotty

Use the published data. Not what people think the powder likes. Published pressure tested data is the only thing you can trust.

[reddog81]

it come from the powder not burning properly causing start/stop/start conditions.
H-110 is more dangerous in an under load situation than an over load situation when it nearly fills the case.

I understand the concepts for using this powder but have never heard of a 90% rule. Did Hodgdon or Winchester ever recommend this practice. Hodgdon has a 60% rule for 4895 in rifle cases so they aren't beyond coming up with these types of practice.

[dragon813gt]

There is no 90% rule w/ H110.

[mdi]

H110/W296 DOES NOT LIKE AIR SPACE........just saying.......

Why? Just askin'...

[swheeler]

Well, see, that's the thing. People say H110/W296 likes a full case, but the load data I'm seeing isn't even close to a full case. What's up with that?

Scotty

Pressure. 357-13.5 Gr H110 with 180 is in the 40k pressure range

[greenjoytj]

See the runfiverun post above. H110 doesn’t work well with reduced charges. If you want a reduced power load you should choose another powder. H110 is for max power/velocity loads.
When you consider the huge fire ball the blasts out the barrel with H110 got to figure a good % of the charge is burning down and outside the barrel. H110 is a slow pistol powder that hard to light and keep lit, so be sure to use a magnum primer, your chronograph will thank you with high velocity readings.
H110 powder is very frustrating to research in load manuals, because every manual states widely different min/max loads. Remember the load manual data is from special lab pressure guns.
They are very tightly chambered and have tight spec barrels to show maximum pressure worsts case results with the components used. Any consumer gun is machined with looser chambers, wider cylinder/barrel gap and looser barrels, all working together to lower pressures from the level measured in the lab pressure gun. I would choose the load recipe from the bullet manufacturer to start with.

[greenjoytj]

Pressure. 357-13.5 Gr H110 with 180 is in the 40k pressure range

CUP or PSI? If the load is published in an official load manual it’s safe.

[swheeler]

"but the load data I'm seeing isn't even close to a full case. What's up with that?" now read my answer and you will understand why I quoted the OP

[scottyp99]

"but the load data I'm seeing isn't even close to a full case. What's up with that?" now read my answer and you will understand why I quoted the OP

Well, you've lost me. That looks like Hodgdon's data for a jacketed Hornady XTP bullet, using a Winchester case and a Winchester SPM primer. If so, I'm using a Cast Performance gas-checked hard-cast boolit, Starline case and CCI SPM primer, so what does it have to do with me? Also, why do people keep telling me to stay within published load data? In my original post I very clearly state that I intend to do just that. I'm still waiting to hear back from Cast Performance to verify or deny it, but I have read claims that Cast Performance recommends a min. of 13 gr and a max. of 14 gr with this boolit using H110/W296, and that's the data that I intend to use, if it's verified. I'm just wondering why so much space in the case? Does H110 tolerate some empty space when you get up there in bullet weight? I've heard folks talk about charges so big with 125 grainers that the powder actually needs to be compressed! Perhaps the heavier bullet has enough inertia that it allows pressure to rise rapidly enough a little air space is ok, and a packed case might actually lead to too much pressure?

Scotty

[725]

Read a proper data manual or suffer the consequences. May I emphasize "suffer"? Please do your range time alone if you don't. I've been injured once and missed closely once when caviler reloaders shot next to me. Truly I wish you the best of luck and hope you have a safe experience in this hobby.

[Estacado]

H-110 is a powder that I check and recheck. There is not much room between min and max loads. I have always been told under min is as bad as over max. It is a max load powder period.

[JonB_in_Glencoe]

People say H110/W296 likes a full case, but the load data I'm seeing isn't even close to a full case. What's up with that?
scottyp99,
What People?

Like the other members here who are replying to you, I haven't heard this full case theory about H110



Also, why do people keep telling me to stay within published load data?
H110 can be a spooky powder if you "play" with the data (your original post implies that you feel you should be loading a full case). It needs a certain Pressure (and heat) to maintain a thorough burn of the entire charge. If you run it near, or at, Max (published charge) It's one of the best magnum pistol powders. Since it's Spooky, I suspect that is why other members here are telling you to go by the books, just to be safe. BTW, that's my advice as well.

[Larry Gibson]

One thing to add to what scottyp99 said; if the H110/296 has not reached it's pressure threshold for efficient burning and the bullet passes the barrel/cylinder gap of a revolver the pressure can have a sudden drop because of venting. This can "put the fire" out so to speak leaving the bullet stuck in the barrel. I have had it happen twice; once in a 44 Magnum with a 429421 and once in a 357 magnum with a 358421.

[mdi]

I'm juat an average reloader and started in '69 with a Lee Loader. I have only used H110/W296 on a few occasions and have no experience with "under min detonations" using H110, but I have heard and read enough not to try to determine how, why or when it happens.

[mehavey]

Uuuuuhhh....

I just went to QuickLoad w/RCBS 180 Sil(FNGC)* and seated it to the standard 1.59" OAL
102% Fill is 12gr/H110/W296/24,000psi/65-80% burn depending on whether revolver or rifle.

OP: Tell us a little more about your cartridge make-up/dimensions.....




* (which I actually have)

[dragon813gt]

Quickload gives erratic results w/ straight wall cases. I don't trust it w/ them especially w/ H110. I've chronoed loads and they didn't match, outside margin of error by a good bit, QL's predictions. It will tell you case fill but I wouldn't trust anything else.

[mehavey]

Over the past 15 years (+) I've found QuickLoad quite dependable -- indispensable in fact when operating using "unlisted" components powders -- after I adjust burn rate upon initial firing of a mid-range load.
Using QuickLoad blind and without a chronograph-- like any initial engineering exercise -- is not advised.

Ya gotta know what you're doing... and willing to do it.



But I again point out the problem w/ the OP's premise of powder load capacity under the 180gr FNGC. I can't see how it could anywhere near what's cited.

[swheeler]

Uuuuuhhh....

I just went to QuickLoad w/RCBS 180 Sil(FNGC)* and seated it to the standard 1.59" OAL
102% Fill is 12gr/H110/W296/24,000psi/65-80% burn depending on whether revolver or rifle.

OP: Tell us a little more about your cartridge make-up/dimensions.....




* (which I actually have)

Something just doesn't sound right on load density?? 102% at 12 grs @ 1.590 COAL, I shoot 12.5 grs with a 195 cast at that length and IIRC-believe it isn't compressed? RCBS lists 12.4 to 13.4 loading for that 180 sil bullet, the Nosler 180 Partition is very similar length to crimp groove and 12.5- 88% and 13.5 Max-95% load density. The OP couldn't understand my cryptic post? the point I was making is that several different cast bullets and jacket bullets of 180 grains list 13.5 grains as a maximum load, "filling the case up" could very well be dangerous.

[gundownunder]

I also load a 180 grain with WW296, and like the OP, I thought the case was supposed to be near full.
I also worked out that a full load would be well over the published data.
This prompted me to contact the Winchester tech team for clarification.
I was told to go with the published data, and they recommended not exceeding the maximum load even though the space is there to do so.

[scottyp99]

swheeler, I think I understand your post now. What confused me was that it had nothing to do with my question. I do appreciate you guys trying to look out for me, and keep me all in one piece, but I'm sure you can understand that it can be a little annoying when it is unnecessary. There's no way for you to know it's unnecessary, so you make sure, just to be on the safe side. I get it.

I have been thinking about it, and have come up with a hypothesis; the trick with H110/W296 is to quickly get it up into the pressure range where it burns efficiently before the bullet has had a chance to travel very far, right? Once that has been accomplished, everything goes OK from then on. With lighter bullets, it's a firm crimp and small airspace that encourages this, as the lighter bullet begins to move before too much pressure has developed. However, with heavier bullets, the bullet's inertia is greater, and a full case would make too much pressure before the bullet started moving, so we now have a situation where the small airspace is not an issue like it is with the lighter bullets. Does that make any sense to anybody else?

Cast Performance's data shows 13 gr to 14 gr of H110/W296, so I have loaded up a dozen each of 13, 13.5, and 14 gr loads. Starline brass, CCI 550 primer, A firm crimp into the crimp groove, with an overall length of 1.57" That's just where it came out with a crimp that I like the look of. These will be test fired in a 4" Ruger GP100, and if everything goes well, a 2 1/2" Taurus Model 66.

Scotty

[watkibe]

Why do people get so mixed up about H110 ? The first thing new handloaders need to hear is "use the data published by the manufacturer, and follow it closely". Shooting/reloading is full of legends and myths. Ignore them. You are not smarter than the powder companies, and even if you are, you don't have a ballistics lab with a pressure gun and barrels.
In my 357, 41, and 44, I use H110 when I want full power loads. At my age, I don't want full power loads all the time anymore, so for more pleasant and easy-to-shoot loads, I use a different powder.

[44MAG#1]

How much can H110 be reduced? Does it depend on the cartridge etc.? Bullet weight? Primer?

[scottyp99]

Why do people get so mixed up about H110 ? The first thing new handloaders need to hear is "use the data published by the manufacturer, and follow it closely". Shooting/reloading is full of legends and myths. Ignore them. You are not smarter than the powder companies, and even if you are, you don't have a ballistics lab with a pressure gun and barrels.
In my 357, 41, and 44, I use H110 when I want full power loads. At my age, I don't want full power loads all the time anymore, so for more pleasant and easy-to-shoot loads, I use a different powder.

Jeez, man, what's up your butt? I don't think I'm smarter than any powder company. I have loading data from the bullet manufacturer, and I'm using it. I have some experience using H110 with 158 gr bullets. I have fairly good common sense. I have an excellent track record of making effective, reliable ammunition in 30-06, 308 Win, 6.5x55 Swede, 303 British, 38 Special, 357 Magnum, and 45 ACP for about 10 years now. And, a PERFECT safety record during that time, also. What more do you want from me, a Master's Degree in reloading?

Anyway, took my experimental ammo to the range today. Bear in mind that it was cold out, about 20 degrees F. The GP 100 was unavailable, so the test was performed using the Taurus 66.I did not fire the minimum load of 13 gr of H110 because of the low temperature. I fired 12 rounds each of the 13.5 and 14 gr loads. They both were pretty hard kickers, with the 14 gr load being very slightly stouter (not surprising, eh?) Extraction was nice and easy, not sticky at all. The CCI 550 primers were noticeably flattened, but still had a rounded edge, I couldn't really tell a difference between the two loads under a 4x magnifying glass. After 5 rounds, the 6th was measured and no change in overall length was noted. When it warms up, I'll repeat this test, starting with the 13 gr load this time. Hopefully, I'll have a chrono by then. (My birthday is in May, and I've already started dropping hints!)

Scotty

[Motor]

Scotty. Load data is developed using pressure as the guideline. Air space within the casing (load density) is already considered before testing begins.

In the past "SEE" (which is basically detonation) was blamed on low load density using ball powders like H-110 but the fact is "SEE" has never been reproduced in testing.

The results of years of testing is just starting to show in the latest data. You have to realise most of the data we have was developed years ago. If you look at new data like data developed for cartridges that were introduced recently you will find a much wider range of charges using H-110/W-296.

Just look at 500 S&W data both jacketed and cast using H-110/W-296. The data blows away all of the old rules of thumb concerning this powder.

This is why so many of us here are saying just simply fallow the published data, use a firm crimp and a magnum primer with H-110/W-296. Some people don't even use the magnum primers in the smaller casings like .357 but I always do.

As far as reduced loads go using H-110/W-296: It may or may not be ok to do. We simply don't know because the people who do the testing have no reason to invest the money into doing it. Honestly why would they bother when there are so many powders available to load light loads. So I don't see it happening any time soon.

Motor

[kingrj]

I have had very good results with H110 and its twin WW296 in everything I have ever shot it in. In my opinion the percent case fill is NOT as important as a good hard crimp on the bullet and running the pressures near maximum for the cartridge. Anytime I strayed from this principle I got poor accuracy and inconsistent velocities. I do NOT think reduced loads with this powder is dangerous..I just think it will yield inconsistent results.

[44Blam]

I shoot 44 mag and I did a little ladder the other day. Most of the sources I saw agree that 24 grn is pretty much max for a 240 grn GC boolit (or jacketed). So, I shot my ladder with both my henry big boy and my ruger redhawk @ 50 yards. I started with the min load I found at 22 grn and laddered up by .5 grn up to 24.5 grn.

I found that with that boolit, 23.5 grain really shot consistently and the groups were less that 1". Funny the 22 and 22.5 grn rounds were pretty good around 2-3" groups, 23 was good, 23.5 was spot on, 24 started to go wild more like 5" groups and 24.5 was really spread out with some rounds off the paper. The handgun has significant recoil in that range, but with the 24.5 grn in the Henry rifle, the recoil is fairly mild...

Anyway, for both my guns with the 240 grn GC boolit I was shooting, 23.5 was optimal. 24 grain was listed as max in the Lee book, there were other places where it listed 24.5, though.

SO - I would say lookup what they say in Modern Reloading and take a couple other sources (be wary of folks on the interwebs - I've seen some crazy suggestions) and compare/contrast. But mostly, H110 and W296 are pretty specific for range.

I just loaded a "side by side" comparison of my ladders that I've done with W296 and Alliant 2400 where it is the same boolit and it is 23.5 grn 296 and 21 grn 2400. I loaded 100: 50 of each. And I'm going to go to the range and decide what powder I really want to shoot... I'm really leaning on the 2400 since I can make some loads for my 45-70 and it can be downloaded fairly easily.

BUT, I really like ~23 grn of W296 in the redhawk because there is a ball of fire that shoots out the barrel. It is awesome "flinch" training. If you pull the trigger and you watch the fireball, you did not flinch. If you see NO fireball, you flinched. ;)

[JonB_in_Glencoe]

How much can H110 be reduced? Does it depend on the cartridge etc.? Bullet weight? Primer?
3% according to a 2011 Hodgdon reloading manual.
They state, "due to inconsistency of velocity", but there are several posts in this thread by people I trust to better explain why it's dangerous.

212125

212126

[44MAG#1]

[QUOTE=JonB_in_Glencoe;4264443]3% according to a 2011 Hodgdon reloading manual.
They state, "due to inconsistency of velocity", but there are several posts in this thread by people I trust to better explain why it's dangerous.

212125

How do you explain in the Hodgdons 2018 Annual Manual on page 155 and 156 for the 357 Mag they reduced the charge for H110 10 percent?
Also in page 159 for the 41 Mag they reduce the charge 10 percent for the 210 bullet? For the 170 they reduce the charge for H110 11 percent.
On page 162 for the 44 Magnum and the 270 they reduce it 9 percent. On page 161 they reduce it 8 percent.

These are just a few that I readily found. In other books such as Hornady they do the same thing.
How does one explain the 3 percent rule when even from the horses mouth they don't follow it?
Things are certainly funny don't you think.

[JonB_in_Glencoe]

Does the 2018 manual have the same 3% warning near the front of the manual with the other numerous warnings?

The warning in the 2011 manual doesn't say, MAX loads should not be reduced by more than 3%. It says, "loads should not be reduced by more than 3%".

[44MAG#1]

Does the 2018 manual have the same 3% warning near the front of the manual with the other numerous warnings?

The warning in the 2011 manual doesn't say, MAX loads should not be reduced by more than 3%. It says, "loads should not be reduced by more than 3%".

Well since we are splitting hairs here. Because if the 2011 manual doesn't say which loads not to reduce more than 3 percent, which to me would be dangerous to not mention it, because how would we know what not to reduce more than three percent, says on a fairly new one pound of H110 I have is this:
MAXIMUM LOADS-DO NOT EXCEED-REDUCE BY 3% TO START.

Now we could say that they are talking about the loads they have listed on the powder container but, if we look on their website the 44 load with the 280 Swift bullet is reduced by 9.75 percent and the 41 mag load the list on the powder container is reduced by 10 percent. True I did not do an extensive search of all calibers but either they are talking out of both sides of their mouth or they could be in error such as the error Larry Gibson found on a rifle load awhile back.
Who really knows? Evidentally you and I don't because I have been in wonderment over their warnings on H110 for years. This isn't the first time I have noticed double talk about H110 from Hodgdons.
So what do we do?
OH YES, they used the Remington 2 1/2 STD primer in their data.
I am sure Hodgdons tested their loads extensively. We should probably go by them.
But the problem is people read something like the 3% thing and it becomes gospel from then on. Everyone does their best imitation of the talking parrot and blathers the 3 percent thing extensively along with the magnum primer thing.
I don't know, maybe it's time the talking parrot thing dies down.
Again I am pretty dumb.

[JonB_in_Glencoe]

How much can H110 be reduced? Does it depend on the cartridge etc.? Bullet weight? Primer?
I am sorry, I didn't realize this was a rhetorical question.




Well since we are splitting hairs here. Because if the 2011 manual doesn't say which loads not to reduce more than 3 percent, which to me would be dangerous to not mention it, because how would we know what not to reduce more than three percent, says on a fairly new one pound of H110 I have is this:
MAXIMUM LOADS-DO NOT EXCEED-REDUCE BY 3% TO START.

Now we could say that they are talking about the loads they have listed on the powder container but, if we look on their website the 44 load with the 280 Swift bullet is reduced by 9.75 percent and the 41 mag load the list on the powder container is reduced by 10 percent. True I did not do an extensive search of all calibers but either they are talking out of both sides of their mouth or they could be in error such as the error Larry Gibson found on a rifle load awhile back.
Who really knows? Evidentally you and I don't because I have been in wonderment over their warnings on H110 for years. This isn't the first time I have noticed double talk about H110 from Hodgdons.
So what do we do?
OH YES, they used the Remington 2 1/2 STD primer in their data.
I am sure Hodgdons tested their loads extensively. We should probably go by them.
But the problem is people read something like the 3% thing and it becomes gospel from then on. Everyone does their best imitation of the talking parrot and blathers the 3 percent thing extensively along with the magnum primer thing.
I don't know, maybe it's time the talking parrot thing dies down.
Again I am pretty dumb.
ahhh, you are not dumb, you seem smarter than most.
I, myself, am a simple man, and what Hodgdon states about their H110 powder seems simple enough for me.
Good Luck on your quest to get answers to all those questions you ask.


I recall, some years back, I was on a quest, a quest where the facts were seemingly equally confounding as this H110 conundrum you pose. Pressure developed from the friction of a bullet going through a barrel. Jacketed bullet vs lubed cast boolit. I was sure a dry copper jacketed bullet would cause more friction and raise the pressure higher than a equally weighted lubed cast boolit being pushed through the same barrel with the same charge. It took a while, but I did find the answers at the end of my quest.

[Steven66]

I am working up a load for .357 Magnum using WW296, Starline cases, CCI 550 primers and (until I get my casting stuff set up) Hornady 158 grain XTPs for my Ruger 77/357. I'm using Hodgdon's data for H110 (which I understand is identical to WW296 by numerous accounts, born out by essentially identical load data from multiple sources) from their 2017 manual. The maximum load in the manual (16.7 grains of H110) lists velocity at 1,757 fps. The last 10 rounds I shot (15.0 grains of WW296) averaged 1,520 fps. I'm going to stop when I get it up to 1,700- ish fps, because that's all I need. I'm pretty sure I chronographed some factory Blazer Brass at around 1,750 fps in the Ruger, but since I didn't record it, I can't be certain and will have to do it over to establish a baseline.

John Barsness (a writer I respect) recommends using a chronograph to assess pressure (rather than flattened primers or difficult extraction). Essentially, if velocities are substantially over those listed in published data, pressures are higher as well.
In my opinion, this is safer than relying on how hard a case extracts. It's always possible that my least expensive Chrony isn't as accurate as it should be, to be fair. Since it's cold now, I'll have chronograph reloads again in summer to make sure I don't exceed velocity/pressure.

If any of the above is incorrect or inaccurate, I would like know about it.

[Motor]

I've seen this discussion about percentages many times. I've also read them many times. This is how I understood it:

The 3% rule pertains the "listed start loads" As in don't reduce the listed start loads by more than 3%.

The 10% rule comes from data sources that only listed a maximum charge weight. They say "The loads listed are maximum and should be reduced by 10% to start"

I believe these are accurate interpretations of both rules.

Motor

ETA: Steven66. I don't see anything wrong with your post. Data varies a good bit. The latest Hornady manual maximum is lower than their older manuals.

I worked my loads up a long time ago and still use 16.8gr W-296 with 158gr jacketed bullets in .357 magnum. They were fine 30 years ago and are still. ;)

[44MAG#1]

I've seen this discussion about percentages many times. I've also read them many times. This is how I understood it:

The 3% rule pertains the "listed start loads" As in don't reduce the listed start loads by more than 3%.

The 10% rule comes from data sources that only listed a maximum charge weight. They say "The loads listed are maximum and should be reduced by 10% to start"

I believe these are accurate interpretations of both rules.

Motor

ETA: Steven66. I don't see anything wrong with your post. Data varies a good bit. The latest Hornady manual maximum is lower than their older manuals.

I worked my loads up a long time ago and still use 16.8gr W-296 with 158gr jacketed bullets in .357 magnum. They were fine 30 years ago and are still. ;)

Understanding can mean many things.
I have before me a relatively new pound container of H110. It list maximum loads for both the 44 Magnum and a 454 Casull.
It says under the load data, and I quote: "Maximum loads-do not exceed-reduce by 3% to start."
It says nothing about not reducing the start loads no more than 3%.
If you go to Hodgdons site the loads they list reduced,the 44 Mag load 9.87% and the 454 load by 5.9%.
The bottom line is if we have load data books we need to use them. Are they infallible, no, nothing man has anything to do with is infallible.
Bottom line is if one has no books to go by then it is time for them to turn loose of the long green and buy a couple at least.
Look at the data, and use the data.
Things like this will not need to be hashed, rehashed etc..
But be careful. Nothing is infallible.

[Motor]

44mag#1
You won't get any arguments from me. I believed I read the "3%" rule in a manual that actually did list a range of data.

Your post just proves that your advice to use actual data is the best rule. As I posted earlier in this thread the very newest data blows away both the 3and10 percent rules.

Motor

[Steven66]

I chronographed ten rounds yesterday, four (forgot to record the 5th) @ 15.4 and five @ 15.5 grains of 296 with the rest of the components the same as in my earlier post. The 15.5 grain load averaged 1667 fps and the 15.4 grain load averaged 1683 fps. Possibly the shot I forgot to record would have normalized the lighter load, but I'm wondering if stepping up charges 0.2 grains (instead of 0.1 as is commonly recommended) is more appropriate for spherical powders like WW296 (because the grains are so fine)? I intend to stop when I hit around 1770 fps, since that's what I get with factory loads (and, by implication, safe pressures). Also, does it seem that crimping is necessary to get a consistent, relatively clean burns with this powder?

[RogerDat]

I don't use that powder much but everything I have heard or read says it needs pressure to burn correctly. So not good for reduced loads, very good in a narrow band of top end loads. Myself I don't like the hand abuse so I seldom want a full power load.

I trim the brass to get a good consistent and snug crimp. Which also avoids unfired bullets walking out on recoil and helps with building consistent pressure. I use published load data. Seldom right at the bottom or right at the top. Wife still gets pissed if she gets one of the "hot" loads. Which is one more reason to not make them in my world. Less chance of pissed off spouse. I do make them from time to time. What is the point of a .357 mag if you only load it to .38 special power?

Seems obvious the case fill "rule" comes from the poor performance and/or risk associated with improper burn from too low a pressure. It also seems pretty clear it like many rules of thumb doesn't stand up to examination terribly well across a range of circumstances.

Manuals vary, same manual different years, different manuals same years etc. You won't get identical data but you will get tested data from all of them. The newer may be more cautious but it will also reflect the current formula and latest testing methods so in theory should be the most accurate.

[Road_Clam]

I use a lot of H110 for 357, 44 , and 460 mag. Excellent powder as long as you stay near max loads. You start loading below 10% of max you will start to see some elevated SD's (standard deviation) in velocities . To the average loader without a chronograph, shooting at 25 ft you won't notice any difference. Shooting a handgun at 25 yds now you start to see stray shots. I've since switched to 2400 if I desire to run milder magnum loads. Just my experiences, YMMV