What is / is there a good powder for .38sp and .357 magnum?

[Hornet35]

Crikey, posted this on another forum and got 1 reply in 4 days!

I thought it as very likely I was asking too much of one powder, especially with the 2 magnum loads. I think I'll give the lil gun load a go, if that works thats the fix load sorted then get a powder for the cast load. Viht powders seem popular from the response, the only think that puts me off is buying by the kg and I will only be using this on one permission and doing gallery 2-4 times a year so quite an outlay.

RE. Stripping lead it was my understanding if you pushed lead too fast and / or if it is too soft it would leave excessive lead fouling which would then ruin the accuracy of jacketed bullets without a deep clean in between. I've never shot cast so it's a bit of a new one on me! (and it should have read 'slow enough to NOT lead foul the barrel)

for the replies!

[ovenpaa]

For the .357Mag 158 grain cast I use TrailBoss or N310 and prefer the TB with around 4.5 grains as an accuracy load at 25m

[Daryll]

If you don't fancy Vit powders, try Alliant.... you will find they're dirtier powders though...

Bullseye or Red dot for gallery loads, Unique or Blue dot for magnums

http://www.alliantpowder.com/reloaders/index.aspx

[Hornet35]

For the .357Mag 158 grain cast I use TrailBoss or N310 and prefer the TB with around 4.5 grains as an accuracy load at 25m

Hmm good shout, I've got a tub of trail boss in the cupboard

[DavidRees]

Viht powders seem popular from the response, the only think that puts me off is buying by the kg

Viht rifle powders (N1xx, and N5xx) are sold in 1 Kg tubs. Pistol powders (N3xx) are sold by the 1/2 kilo -- 500 grams, which is 7700 grains -- 10% more than the 1 lb (7000 grains) tubs of powder from the USA.

Viht N3xx powders tend to sell around the £39-£42 mark. Kranks sell it at £39 per tub of 1/2 kg.

The Viht 2014 (edition 13) reloading manual gives .357Magnum loads for N340 in the bullet weights you are interested in:
110gr Hornady HP/XTP starting load: 9.3gr N340, giving 1558fps, up to a maximum load achieving 1639fps.
140gr Speer HP starting load: 8.2gr N340, giving 1325fps, up to a maximum load acheiving 1385fps.

Both of the above are measured in a 7" barrel; through your Rossi, you can reasonably expect an extra 100pfs or so above the velocities given above.

[dromia]

RE. Stripping lead it was my understanding if you pushed lead too fast and / or if it is too soft it would leave excessive lead fouling which would then ruin the accuracy of jacketed bullets without a deep clean in between. I've never shot cast so it's a bit of a new one on me! (and it should have read 'slow enough to NOT lead foul the barrel)

for the replies!

Velocity doesn't cause leading especially in these relatively low velocity cartridges, where did you get that idea from?

It is poor cast bullet fit and too hard an alloy that causes leading.

Copper bullets foul the bore with nasty copper that builds up and is difficult to remove without specialist cleaners, good lead bullets do not lead foul the bore and isn't cumulative like copper jacketed.

You seem to have your fouling information back to front.

[Hornet35]

Viht powders seem popular from the response, the only think that puts me off is buying by the kg

Viht rifle powders (N1xx, and N5xx) are sold in 1 Kg tubs. Pistol powders (N3xx) are sold by the 1/2 kilo -- 500 grams, which is 7700 grains -- 10% more than the 1 lb (7000 grains) tubs of powder from the USA.

Viht N3xx powders tend to sell around the £39-£42 mark. Kranks sell it at £39 per tub of 1/2 kg.

The Viht 2014 (edition 13) reloading manual gives .357Magnum loads for N340 in the bullet weights you are interested in:
110gr Hornady HP/XTP starting load: 9.3gr N340, giving 1558fps, up to a maximum load achieving 1639fps.
140gr Speer HP starting load: 8.2gr N340, giving 1325fps, up to a maximum load acheiving 1385fps.

Both of the above are measured in a 7" barrel; through your Rossi, you can reasonably expect an extra 100pfs or so above the velocities given above.

Thanks, didn't realise they came in smaller tubs, I've just checked and dauntsey guns have pistol powders at £41.

Interesting that the extra 13" of barrel only gives extra 100fps, I guess it's a pistol load so the powders all burnt up too soon to make the most of the extra length.

Hodgdon seem to be alone in giving rifle loads for .357, H110 for the xtp starting at 17.1 gr giving 1836 fps, max load 19 gr giving 1997 fps so looks like this gives me the best chance of getting small deer legal. For the 110s they list 22 gr giving 2291 fps, max load 23gr giving 2398 fps. Good velocity gains over the n340 but over double the powder burned, decisions, decisions!

[Hornet35]

RE. Stripping lead it was my understanding if you pushed lead too fast and / or if it is too soft it would leave excessive lead fouling which would then ruin the accuracy of jacketed bullets without a deep clean in between. I've never shot cast so it's a bit of a new one on me! (and it should have read 'slow enough to NOT lead foul the barrel)

for the replies!

Velocity doesn't cause leading especially in these relatively low velocity cartridges, where did you get that idea from?

It is poor cast bullet fit and too hard an alloy that causes leading.

Copper bullets foul the bore with nasty copper that builds up and is difficult to remove without specialist cleaners, good lead bullets do not lead foul the bore and isn't cumulative like copper jacketed.

You seem to have your fouling information back to front.

That's quite possible, I remember when I was looking at a subsonic load a while back for the hornet cast was the preferred option but people were telling me that switching lead to jacketed would cause issues with accuracy for the latter unless the lead fouling was scrubbed clean, I may have remembered it the wrong way around though!!

[dromia]

If you have lead fouling then your cast bullets are wrong.

It is good practice however to remove all copper fouling from a barrel before shooting lead as the copper fouling can in some cases cause inaccuracy for lead bullets.

[Richardd]

I'm also a reloading newbie (for my .38/357 Taurus and Rossi underlever) and have, so far, been loading 38spl only using different heads trying to find the shape that is most accurate and consistent over a number of distances.

So far I've been using factory bullets (Magtech Cowboy load) as a 'control' and although RNFP they're more like a TC. For reloading I've been using GM 158gr RNFP with 4.3gr Unique with mixed results. I can get a 3" grouping at 25m (standing) but totally inconsistent at 50m & 100m.

I've bought some GM TC, PPI SWC and Jacketed (all 158gr) and loaded them to 4.3gr of Unique (and some to 4.9gr) as well but not had a chance to shoot them. Once I've sent some up the range I'll have space in my allowance to try loading some at .357 to see if that make an accuracy difference. I've been worried about leading (thus the jacketed rounds) but the .357s are likely to be more for entertainment than completer accuracy ;-)