Anyone familiar with VihtaVuori 3N37 Powder?

[FoghornLeghorn]

It's from Finland, I think?

I ordered some but want to clarify some load parameters since none of my manuals mention this brand.

For my 357 revolvers. They're all old, no longer manufactured. Etc. Pythons. 27-2s/pre 27. 66 no dash/-1. Etc.

Because of their age, I don't shoot magnum loads in them. I load loads around the level of 38 special +p.

These will be once fired cases, mixed headstamp, Berrys plated 148 grain double ended wadcutters.

I typically load ~5 grains Unique but am going to experiment with the VihtaVuori given current supply chain problems. Saving my Unique, so to speak.

On their website, VihtaVuori does not give data for a 148 grain bullet with the 3N37 powder. They do give data for a 146 grain bullet. Starting load 5.4 grains=863 fps. Max load 6.1 grains=1018 fps.

There shouldn't be any problem starting with 5.4 grains for a plated 148 grain bullet, correct?

 

[markr6754]

This is one of my favorite powders for 9mm and 40 S&W. I haven't used it in 357 Magnum. Are you loading 38 SPL cases or light loading 357 Mag cases?

In any event, I'd think you'll find a starting load of 5.4gr with the 148gr Berry's bullet will be no where near 38 Spl +P. The +P load starts ABOVE max load for 38 Spl, or 6.1gr. If you're loading that into a 357 Mag case I'd be more worried about complete powder burn with that light of a charge.

 

[74A95]

These will be once fired cases, mixed headstamp, Berrys plated 148 grain double ended wadcutters.

I typically load ~5 grains Unique but am going to experiment with the VihtaVuori given current supply chain problems. Saving my Unique, so to speak.

On their website, VihtaVuori does not give data for a 148 grain bullet with the 3N37 powder. They do give data for a 146 grain bullet. Starting load 5.4 grains=863 fps. Max load 6.1 grains=1018 fps.

There shouldn't be any problem starting with 5.4 grains for a plated 148 grain bullet, correct?

Will you be seating the Berry wadcutter deep like most wadcutters - i.e. flush with the case mouth?

If so, DO NOT load with 5.4 grains!!!!! Note that the data you quote is for a bullet seated long (1.378"). But a wadcutter will be seated to ~1.181". That's too deep for 5.4 grains.

Note that 3N37 and N350 have about the same charge weights and speeds. Use the N350 charge weights (for 3N37) for the 148 WC bullets seated flush. start = 4.1 gr., max = 4.6 gr.

Pay very close attention to OAL!!!

 

[FoghornLeghorn]

Are you loading 38 SPL cases or light loading 357 Mag cases?

The latter, light loads using 357 mag cases.

 

[markr6754]

Will you be seating the Berry wadcutter deep like most wadcutters - i.e. flush with the case mouth?

If so, DO NOT load with 5.4 grains!!!!! Note that the data you quote is for a bullet seated long (1.378"). But a wadcutter will be seated to ~1.181". That's too deep for 5.4 grains.

Note that 3N37 and N350 have about the same charge weights and speeds. Use the N350 charge weights (for 3N37) for the 148 WC bullets seated flush. start = 4.1 gr., max = 4.6 gr.

Pay very close attention to OAL!!!

I'm certain that you have more experience than I do, and I don't load wadcutters. That said, I think you are far off on this one.

Here is data from Vihtavuori Load Manual 2002 for 38 Spl (not +p), but he is charging 357 Mag cases. I've converted data to US standard measures from metric

38 SPL loads
148gr LWC Sako COL 1.181"
3N37 6.1gr 915fps - 6.8gr 1,049fps
N350 5.9gr 925fps - 6.7gr 1,066fps

357 Mag loads
145gr LSWC Intercast COL 1.614"
3N37 7.5gr 1,270fps - 8.5gr 1,368fps
N350 6.8gr 1,230fps - 8.1gr 1,345fps

The bullets are a close approximation to what he is planning to load. In each case, he is well under the minimums for the loads...which is why I believe that his charge will be to soft. For sure, he is starting low, with plenty of room to work up.

 

[74A95]

I'm certain that you have more experience than I do, and I don't load wadcutters. That said, I think you are far off on this one.

Here is data from Vihtavuori Load Manual 2002 for 38 Spl (not +p), but he is charging 357 Mag cases. I've converted data to US standard measures from metric

38 SPL loads
148gr LWC Sako COL 1.181"
3N37 6.1gr 915fps - 6.8gr 1,049fps
N350 5.9gr 925fps - 6.7gr 1,066fps

357 Mag loads
145gr LSWC Intercast COL 1.614"
3N37 7.5gr 1,270fps - 8.5gr 1,368fps
N350 6.8gr 1,230fps - 8.1gr 1,345fps

The bullets are a close approximation to what he is planning to load. In each case, he is well under the minimums for the loads...which is why I believe that his charge will be to soft. For sure, he is starting low, with plenty of room to work up.

The 38 Spl. data I cite comes directly from the current 2021 Vit load manual.
https://www.vihtavuori.com/wp-content/uploads/2021/02/Vihtavuori_Reloading_Guide_2021_USA_www.pdf

The oldest Vit manual I have is #10 from 2012. It's load data matches the current manual for 2021.

The old 38 Spl. data you list is very similar to their current data for 140/146 grain bullets loaded long.

Any dispute with load data will have be left to Vihtavuori.

He did not indicate that he was using 357 mag brass, and that can certainly change the numbers if the OAL is to fit that round's length.

 

[74A95]

Here is data from Vihtavuori Load Manual 2002 for 38 Spl (not +p), but he is charging 357 Mag cases. I've converted data to US standard measures from metric

38 SPL loads
148gr LWC Sako COL 1.181"
3N37 6.1gr 915fps - 6.8gr 1,049fps
N350 5.9gr 925fps - 6.7gr 1,066fps

I found a Vit 2/2002 manual. Here is what it shows for 38 Special 148 WC data.

148 LWC Sako 1.181 OAL
N320 3.2 820 3.4 848
N330 3.6 840 3.7 875
N340 3.9 863 4.0 895
N350 4.3 892 4.5 928

 

[FoghornLeghorn]

He did not indicate that he was using 357 mag brass

Correct. Sorry.

I use only 357 mag cases as I avoid the rings that accumulate in the chambers from consistent use of 38 special cases in 357 mag cylinders.

Ditto 44 mags. I also have older P&R S&W 29-2s as well as a 3 screw Super Blackhawk and I don't like to subject them to magnum loads. So I load mag cases down to special velocities as well.

But thanks for all the information 74 and Mark.

 

[markr6754]

I found a Vit 2/2002 manual. Here is what it shows for 38 Special 148 WC data.

148 LWC Sako 1.181 OAL
N320 3.2 820 3.4 848
N330 3.6 840 3.7 875
N340 3.9 863 4.0 895
N350 4.3 892 4.5 928

Very weird....here's a screen shot of my page and the book cover. Odd indeed.

 

[74A95]

I'll be damned. that is weird.

Note they have N340 and N350 listed twice, the second series has higher charge weights. Must be an error made by whoever put the manual together.

My front page looks like your front page but lacks the word "Metric".

Weird stuff.

 

[FoghornLeghorn]

Given the discrepancy between the above notes, it's still ok for me to use 5.4 grains 3N37 powder w/148 grain plated DEWC in a 357 case?

thanks