170 gr Keith SWC and H110

[OlympicViking]

I’m in the process of loading up some 170 gr Kieth SWC freedom seeds over H110. I’m using bullets I bought from Rim Rock Bullets; they don’t specify what mold they use, but I’m 99% sure it’s the 358429.

https://rimrockbullets.com/xcart/-357-keith-swc-fb-170-gr-per-500.html

My Lyman cast handbook specifies an OAL of 1.553” and 14.4-15.0 gr of H110. Small aside, but H110 specifically states on the packaging that loads must never be reduced more than 3% from maximum, and .97 x 15 = 15.55, so I started at 14.6 gr.

The issue I’m having is that the specified OAL would mean I have to crimp at the forward driving band. I’m loading for a Smith and Wesson 686, and the rounds have plenty of room when I seat to the crimp groove with an OAL of 1.635”. My concern, however, is that H110 is rumored to behave unkindly at reduced loads, and if I load to the crimp groove like I want to, I’d essentially be creating a reduced load, even at the max charge of 15.0 gr.

I have Unique and 2400 I can use, but I prefer to save that for some different pet loads of mine. I have 8 lbs of H110 to get rid of so I want to use it for these heavy SWCs.

Does anyone have experience with this bullet and this powder? Absent any advice I plan to start at 15.0 and if need be I’ll slowly work up. I realize these bullets are very long and were designed for .38 Spl cases in N-Frame guns, and that 1.635” may not chamber in all guns, but I checked and they do chamber in mine, so that’s what I’ll go with.

 

[lightman]

I like the bullet but have not loaded it with H110. I use 2400. Guess I'm old school! It shoots well in several different revolvers. I have one revolver that I have to seat it deep and crimp over the driving band. It shoots well enough.

I have cast this bullet from 2 different molds. The first was an RCBS 150 SWC mold that I had RCBS cut a little deeper for me, creating a 170 grain bullet. The other is an original H&G 4 cavity mold.

 

[Bfh_auto]

I’m in the process of loading up some 170 gr Kieth SWC freedom seeds over H110. I’m using bullets I bought from Rim Rock Bullets; they don’t specify what mold they use, but I’m 99% sure it’s the 358429.

https://rimrockbullets.com/xcart/-357-keith-swc-fb-170-gr-per-500.html

My Lyman cast handbook specifies an OAL of 1.553” and 14.4-15.0 gr of H110. Small aside, but H110 specifically states on the packaging that loads must never be reduced more than 3% from maximum, and .97 x 15 = 15.55, so I started at 14.6 gr.

The issue I’m having is that the specified OAL would mean I have to crimp at the forward driving band. I’m loading for a Smith and Wesson 686, and the rounds have plenty of room when I seat to the crimp groove with an OAL of 1.635”. My concern, however, is that H110 is rumored to behave unkindly at reduced loads, and if I load to the crimp groove like I want to, I’d essentially be creating a reduced load, even at the max charge of 15.0 gr.

I have Unique and 2400 I can use, but I prefer to save that for some different pet loads of mine. I have 8 lbs of H110 to get rid of so I want to use it for these heavy SWCs.

Does anyone have experience with this bullet and this powder? Absent any advice I plan to start at 15.0 and if need be I’ll slowly work up. I realize these bullets are very long and were designed for .38 Spl cases in N-Frame guns, and that 1.635” may not chamber in all guns, but I checked and they do chamber in mine, so that’s what I’ll go with.

I've loaded 180 WFN and RNFP at 15 GR of H110 so I think you are on the right track.
When I get home I will try to remember to check my RCBS cast bullet book. It has data for 170 gr gas checked.

 

[OlympicViking]

Update: I perused my One Book One Caliber manual (2016) for .357 magnum and I see that in their Lyman section they show data for a 358429 bullet weighing 168 gr again at 1.553” A small sample of 10 of the bullets I have on hand ranged from 169.2 to 170.6. What is different this time is that this data specify a max charge weight of 15.7 gr of H110 at 39,800 CUP. Of note, the max charge of 2400 is the same in OBOC and Lyman Cast Bullet Handbook, 13.5 gr at 41,100 CUP.

I have a range trip planned tomorrow, so I will test a few rounds at 15.7 gr and report back. I feel confident in loading to that charge weight, as I’m seating the bullets .082” farther out than specified. My crude math gives that about a 12.3% increase in case capacity compared to the book length. If anything I’m nervous about the couple rounds I have at 14.6 gr being too light.

 

[OlympicViking]

Earlier today I tried 15.5 gr and 15.7 gr H110. The recoil was a big push, but not unpleasant at all. Both loads were very accurate at 10 yards. In single action my shots were one ragged hole when I did my part. I’ve found my new favorite load!

Even my dad, who has hardly any experience with a DA revolver, asked for a second cylinder!

 

[2ndtimer]

Earlier today I tried 15.5 gr and 15.7 gr H110. The recoil was a big push, but not unpleasant at all. Both loads were very accurate at 10 yards. In single action my shots were one ragged hole when I did my part. I’ve found my new favorite load!

Even my dad, who has hardly any experience with a DA revolver, asked for a second cylinder!

When you use up your 8 lbs of H-110, you might consider trying a pound of Power Pistol. I load 7.9 gr behind a Keith Style 170 gr SWC for around 1250 fps out of a 6" GP-100. 90% of W-296/H-110 performance with half the powder. Good accuracy, too.

 

[OlympicViking]

When you use up your 8 lbs of H-110, you might consider trying a pound of Power Pistol. I load 7.9 gr behind a Keith Style 170 gr SWC for around 1250 fps out of a 6" GP-100. 90% of W-296/H-110 performance with half the powder. Good accuracy, too.

I love PP! I actually have a 4 lb jug of it that’s still got anywhere between 1 and 3 lbs in it. I would’ve thought it would be better suited to 125 and 135 gr loadings, but I might try some with these for the fun of it.