Wasn't expecting this at all. Lyman #49 calls for 21.6gr as a starting load for 44 Mag 240gr cast rifle load. I know I was dropping 21.7.

Primers: CCI #350 Large Pistol Magnum.
Gun: Winchester 1892, 20" BBL.
Bullet: Bayou coated 240gr
Brass: Starline

On the left is 21.7 grains of IMR 4227. On the right is 22.5 grains of W296 . What could be some of the reason I got high pressure signs on a starting load?

Check your scale? At times I get way to busy to do much reloading so when I do get restarted I have to recheck my settings on my scale to be sure I'm setting it to the right weight. Have caught myself a few times with the WRONG weight setting and that can get you in big TROUBLE. Your high pressure may be a result of a simple mistake, it happens, Your human.

Good point on the scale, Buckey. It's a Lyman Range Master 750, and I calibrate every time I turn it on, but have no real means of verifying. I think I just talked myself into buying a mechanical scale for exactly that purpose.

Get the check weights that I keep saying that I'm going to buy.

I use a balance beam but I'd still like a check now and then.

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"He was kinda funny lookin'"

The Range Master 750 comes with check weights for the calibration process, but I now feel the need to verify the powder charges on an entirely separate scale. It's just more reloading stuff, so why not? Might as well throw in a chrono and get free shipping from cabelas.

CHECK ALTERNATE SOURCES for your reloading data. As for why, Lyman's 49th lists 24.0 grains as maximum for this combination. The Lee 2nd lists a 22.0 grain Compressed charge as maximum. This isn't the only case where I've found Lyman's data to be a bit on the "hot" side and as a result I never rely on the Lyman as a primary source for load data.

What is the diameter of your coated bullet?
If it is larger than expected, it could cause excess pressure.

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Nemo

Is it possible that cartridge was too hot when you fired it? I had a situation where a load that was several grains below max gave me a flattened primer. (They were work-up loads that were individually weighed on a beam scale.) After thinking about it I remembered I had loaded the rounds but sat the hot gun down for a few minutes before firing it. I don't know how temperature sensitive I4227 is, mine was with H110. Just a thought.

I lost confidence with my electronic scales & went back to my Ohaus M5 for regular use.

.

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Waiting for the break of day

We had a few hundred very high dollar digital scales in the research lab I worked in and there was a guy that came in every month to check them and tune them up. That tells me something.

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"He was kinda funny lookin'"

I don't think you should conclude that your 4227 load was high
pressure based on one round. That primer is not flattened like one
is from excessive pressure. CCI primers are notoriously hard to fully
seat and a primer that is slightly high will flatten a little more than
one that is fully seated. Read the section of your loading manuals
on primers and pressure. The pressure needed to really flatten primers
are normally seen only in centerfire rifle loads and are far in excess of
your less than maximum 44 loads. Look at the pics of primers that
most loading manuals have in the pressure section.

The cups for Rifle primers are made using thicker stock than those for Pistol primers so I believe a statement like this may be somewhat in error. So, a 45 ACP won't show the primers flattening with an over pressure load but a high pressure caliber such as the 44 Magnum certainly could show the primers flattening.

I once made the mistake of using data from the Speer 14th to load a 140 grain Hornady XTP in 357 Magnum using Accurate #9 and the result was flattened primers AND cases sticking in the cylinder. When I got home I downloaded the Hornady manual to my Kindle and discovered that the load I was using was .3 grains over the maximum for this particular bullet per Hornady. Point is, Handgun primers will show flattening when pressures get too high. Fortunately for me I didn't do any damage to my revolver but it was a lesson to not rely on just one source of data.

I don't pay too much attention to primers because, as shown in the Speer manual, you can be way overpressure and have normal looking primers. Or have cratering with SAAMI compliant loads due to the configuration of the firing pin and recoil shield. My 629-5 cratered primers but I never worried as the extraction was easy.

Is it even possible to get to 35ksi with an uncompressed load? 4227 is slow for the case capacity. Recommended for accuracy loads that don't beat up gun or shooter, too much.


"New" IMR4227 is supposed to be slower than old 4227 because it's now the same as H4227.

I think Scooter123 is onto something. The Hodgdon load data center also list max charge (compressed) as 22.0gr.

That was not the only round with a flattened primer, just the worst one. I need to confirm my powder charges on another scale. If that was in fact 21.7gr that flattened primers, I obviously need to back down for a lower starting point.

Did you experience difficult extraction?

My normal load that I have been using for 30 years is 23 gr of IMR 4227 with a hard cast 240 and CCI 350 primers. Unless they have changed the burning rate of IMR 4227 you can't get enough in a 44mag case with a 240 gr bullet to get into trouble. With a 44mag primers are not a real good way to determine pressure problems, usually as soon as the cases start getting hard to extract it's time to start looking hard and doing some measuring.

I did *not* experience difficult extraction. What's causing me so much confusion, is why did the the 4227 primers go flat, and 296 primers didn't? The 22.5gr 296 load is listed as hotter by 200fps at the muzzle. Both charges were measured on the same scale and not a single flattened primer from 296 batch.

The left primer shown is not a flattened primer or a sign of excessive pressure. The edges of the primer are still rounded, it is just getting close to "normal" full magnum load.

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H Richard
SWCA1967 SWHF244

Scooter123, where'd you find the Kindle edition of the Hornady manual? Your post prompted me to look for it, since I have a Kindle, and I don't see a Kindle edition on Amazon's web site.

I assure you they are not rounded, and have fully consumed all available space in the primer pockets, and then some.

Some weapons when made are just a little different than most
and will not hold up as well with maximum charges. They are
not "Lemons" and may over time break in and allow higher pressures.
One reason to work up on loads with any weapon when loading
since there is no way one will know what a certain load will do
in any weapon, until tested.

As a note;
a nickel weighs in at 5 grams........... if you need to check your scale.
A penny comes in around 3.11 grams.

Shil, I used the Search function on my Kindle and did a search for "Hornady". On the list of options available was the Hornady Reloading Guide. I will also note that it has a warning that it may not display properly on the base Kindle but by zooming in on the page the text does become visible and readable. It's not the most convenient data to use but late on a Sunday it was a quick way do find out what I had done wrong. One of these days when I see the Hornady manual at a Cabela's or Bass Pro I plan on picking up a real paper edition but for now it's useable if a bit of a kludge.

Yes and I'm well aware of this because I had problems from
using data from the old Speer #8 manual with 140 gr HPs
and 4756 in my strong S&W 28-2. But rather than assuming
I suggest you read the sections in your Speer manuals on
primers and pressure and look at the pics.

In my experience magnum revolver loads always flatten primers, to the point of embossing them with machining marks of the recoil plate. Watch for signs of extrusion into the firing pin hole.

Primer appearance is not a reliable indication of pressure. There is a lot of variation between brands, and some calibers run at higher pressure. Compressed loads can spike pressure, and result in detonation if carried to extremes, even with black powder. Careful near upper limits! Some bullets seat deeper than others, and powder density, hence volume, can vary, even batch to batch and with humidity.

Thanks, Scooter. I'm going to check it out, just for curiosity's sake. My own Hornady manual is getting a bit dated (Seventh Edition). I think a new paper edition is in the near future for me as well.

The 5 and 20 GRAM weights for electronic scales to calibrate with ARE NOT check weights! Check weights are in the 1 to 5 grain area, and sometimes smaller. RCBS sells 2 different check weight sets, and together, they make a really good set. If you have a friend with a good chemistry scale, you can make your own! On my digital scale I make up a weight for a powder charge, then use this to zero the scale and then add powder to zero. I can re-zero the scale as often as I feel necessary.

BTW, the primer that you are complaining about, looks nothing like an over the top high pressure load. They look like either a black ring around primer or the primer and the case are only distinguishable by color. The head space on your 92 could be a few thousandths long and produce this or mild cratering. I wouldn't worry about it, but it is you gun. Ivan

Hi,
Couple of thoughts:
-The Lyman data is probably for a cast lead bullet of No. 2 alloy. The change in bullet is a possible culprit.
- Those CCI magnum primers can be tough to seat, depending on brass. Maybe try WLP or Federals?
- Reading a primer is an iffy proposition for determining pressure. A more reliable method, at least for the non-laboratory based handloader, is to measure case expansion with a dial micrometer just ahead of the case head. Compare a fired case to a sized but unfired case. Shouldn't be more than .002-.003" expansion. You could also compare to a fired case from one of your other trusted loads.
Best regards,
Jim

FWIW, Hornady did exactly that to set maximum in the old manuals, except they cut off at 0.0005". In other words, unmeasurable with a common micrometer. Also, they excluded compressed loads.
Setting maximum in that way, my 1975 edition says 23 gr is the maximum load with a 240 JHP bullet (case full? Seating depth .371") . Absent incorrect seating depth, overcrimping, or bullet setback I think there is a symptom but no disease in the OP.

An ordinary micrometer is perfectly capable of measuring to half a thousandth. The divisions are wide enough you can interpolate tenths by eye. The addition of a vernier simply makes this interpolation more objective.

Whether the reading is accurate to a tenth is another matter. Technique is of paramount importance. Check your technique using a test ring or Jo blocks. A springy medium like a brass case is nearly impossible to measure at that accuracy with a micrometer, but the nearest thousandth is reasonable.

I have a Mitutoyo digital vernier caliper which reads to 0.0005". It's a lab grade instrument, but the actual accuracy in the field is probably closer to 0.002". If you want tenths, make room on your bench for an optical comparator.

You will find that some guns just do not "like" some components. I have had start loads tie up the revolver. Not sure why this is, it is just an observation. Factory ammo can be the same. It is best to test until you are satisfied the load meets your requirements.

Some years ago, when hot loading the 45 Colt was just starting to be popular a gun writer made up some loads with heavy bullets. The cases just fell out of the cylinder and primers were rounded and looked perfect. He sent some out for pressure testing and they were around 65,000 CUP IIRC.

Lets not forget what actually happens in revolvers when they fire. Clearance from the recoil shield allows primer to back out slightly before the whole case recoils and essentially slams the primer back in. It's why when you use wax or rubber bullets you can lock up your revolver from primers backing out.

Other signs such as sticky extraction and cratering are more reliable in revolvers.

You would be hard pressed to overload IMR4227 in .44 mag under a 240 gr bullet. Just ain't enough room in the case. A plated bullet is not a lead bullet or is it a jacketed. It falls in between and should be loaded as such. Lyman's start load for a jacketed 240 pill in .44 is 19.3. Something to think about.

FWIW
Not sure what's going on with that load but I've seen a ton of loosey goosey winchester 30-30's do that with both factory and starting loads made up in new brass. If you were careful not to set the shoulder back the primers looked totally different with the same starting load on the second go round.