357 Magnum & H110 low velocity

[460harry]

Uh, Hodgdons published MAX with an 180gr Nosler Partition and Longshot is 7.2 gr @ 1,167 out of a 10" barrel... Pressure shown as 41,700 CUP.

Something here doesn't make sense to me as I can't believe there is THAT MUCH difference between that Nosler and a 180 gr XTP...?

Unless...?

No, the difference is the barrel length. With 10 inches you get far, far more burn and pressure out of the powder compared to just 4 inches, and so you need more powder at 4 inches to get equivalent pressure/burn. I checked the brass at 8.5 grains, no sticking to the cylinder and the case head looked fine. That was thrice shot brass too.

 

[buck460XVR]

I would try loading some up with 16 gr instead of 17.5 and see what you get. I've found that sometimes you get to the point when adding more powder, that velocity actually decreases at a point. H110/W296 likes a firm crimp for best ignition too. Was the 158 grainer jacketed or plated?

 

[Greenjoytj]

Yes! Yes! Yes! If you take a LARGE sample size and if you have four decades behind a chrono and you have experience using them, I totally agree!

I have a Chrony Beta Master. Lots of us call is the Master Beta, heh. I also call it "the fun sucker."

Chrony does well: clocking loads

Chrony does not well: interface. Power of a 1985 super computer but wholly controlled with only three click buttons.

Chrony does TRAIN WRECK AWFUL: here is a device that can do extreme college level math (standard deviation, not simple addition here) and it limits you to a 10-shot string.

10 shots! Have you got a potentially great load, and a low SD interests you? Well here is the CHRONY, where 10 shots is the limit of it's ability.

If I had a load that looked good, I'd want 30 or 50 shots. Sample size! But if you have a CHRONY, sorry bout your luck.

10 shot strings are the minimum required for statistical relevance.
You need to make many 10 shots strings and average the results.
Also test the load in different temperature extremes summer & winter.

If a reloader only cares about creating a the most accurate handload then a chrono is not a required piece of reloading equipment.
But if the reloader is always wondering what his MV is then he a chronograph should be his second purchase, right after acquiring a library of reloading manuals.

Too bad the Shooting Chrony company closed.

 

[moosedog]

H110 was designed for 410 shotguns and 44-45 caliber heavy loads.

 

[M29since14]

It's always interesting to me that H110 seems to work OK in the .410 at about 12,000 PSI but we are cautioned not to reduce it much in the .44, below say 30,000 PSI. I'm sure there's a logical explanation but I've never heard it.

 

[Greenjoytj]

I've read that to help H110 to be a slow burning powder, the granules have been well coated with a flame deterrent. This makes it hard to light which is why magnum primers are specified in the reloading manual recipes.
The deterrent coating also makes this powder difficult to keep lit, so squib shots are a real possibility with reduced charge weights that reduce close packed density of the powder charge prior to primer ignition.
Also a good crimp is always recommend it keeps the powder bunched a little longer to assist most the granules start to burn before they are separated as they get blown into the expanding space behind the bullet.
It's in this expansion space the granules burn engulfed in red hot plasma still burning and still building pressure which make the high velocity the slow burning powders provide along with fire ball at the muzzle.

 

[Rogeronimo]

I dumped H110 and made some Hodgdon Longshot loads today with 357 Magnum. Huge improvement over h110. 8.5 grains of longshot with a 180 grain xtp using a small pistol magnum primer, and I averaged 1,161 fps across 5 shots. Between this and 357 Sig, I feel like Longshot is the perfect small pistol magnum powder for short barrel guns.

Totally agree! I actually use 3N38 for all of my 357 short-barrel loads for the very same reason, and they are quite stout. Excellent accuracy.