40 S&W down loading (Sparkover)

[speedy169]

I was thinking about down loading some $) to shoot some steel and production, but have received allot of warning about down loading the 40 to much due to spark over. What the heck is sparkover?

From what I have heard it is were the primer will light off the powder in the front of the case before it lights off the powder in the back of the case. Now I don't know if this is more apt to happen with slower burning powders or faster burning powders. I guess a little down loading 101 for the 40 is in order.

I currently load 4.9gr of American select under a 170gr LSWC in mixed brass with SP primers (usually WIN but switching to wolf Primers).

Thanks for any helpful info.

Edited January 9, 2009 by speedy169

[HSMITH]

I've never had a problem downloading 40.

[Scoterbeast]

I was thinking about down loading some $) to shoot some steel and production, but have received allot of warning about down loading the 40 to much due to spark over. What the heck is sparkover?

From what I have heard it is were the primer will light off the powder in the front of the case before it lights off the powder in the back of the case. Now I don't know if this is more apt to happen with slower burning powders or faster burning powders. I guess a little down loading 101 for the 40 is in order.

I currently load 4.9gr of American select under a 170gr LSWC in mixed brass with SP primers (usually WIN but switching to wolf Primers).

Thanks for any helpful info.

I download a SVI limited gun for steel all the time - no problem whatsoever unless getting too used to soft shooter is a problem.

[Viggen]

Not that I have heard it all, but where did you come across the term "sparkover" in relation to reloading ammunition, specifically pistol ammunition?

Never had a problem downloading any pistol cartridge .

But with a Rifle you DO NOT download beyond a certain point using the standard rifle powders - long dissertation so will not continue.

Edited January 9, 2009 by Viggen

[Squishy]

Been down loading 40 ( steel and IDPA ) with very fast powders for years . Never had a problem.

[Cy Soto]

For those that are saying pict you have downloaded, do you mean that you are loading bellow published load data?

[Flexmoney]

There is a lot of info on 40 Minor in the Reloading section of the forum.

[TonyT]

I have used 3.6 to 3.9 gr. WST with 155 to 180 gr. jacketed bullets in my CZ-40B S&W 646 and S&W 610. Nice mild, clean burning, accurate loads

[buddy_fuentes]

For my major loads I use N-320 and a 185 grain LTC bullet. When shooting steel I use the same powder and charge, but use a 140 grain LTC and have used the 155 grain LTC bullets also. I have played with lighter charges and saw no real difference. Swap the bullets and keep it simple.

Buddy

[z40acp]

I think the problem that you are describing normally occurs in calibers with larger cases. In Cowboy Action Shooting they are using cases that were designed for blackpowder loads. A 45 Colt case with a small amount of powder leaves a lot of room. That is one of the reasons Hodgdon made Titegroup, it is not supposed to be as sensitive to powder location. So you should not have to worry about .40 with reasonable downloads.