Need help with plated .40s and Vihtavouri

[Southernsorrow]

This will be my first time using "plated bullets" I've always used TMJ 180/165 grs. I figured since this is going to be mostly target and plinking ammo I would just save the extra 40-50% of cost and went with some plated rounds. I have ahold of 250rnds each of Rainier 165gr. RNFP and Berry's 180 dblstrike RN. on another note, My sigs seem to give better accuracy with round nose vs the typical flat nose cone. Out of the 2 brands, the berry's seem to have a better jacket type finish while the rainiers look like painted or copper washed lead.

I was wondering if anyone knows a good start/stop point using Vihtavuori
N320 and N340 "I'm almost out of n340 but I have 2lbs of n320 left"

Since these are plated, I'm pretty sure they should be loaded to lead specs but I can't seem to find any info on 165gr and very little on the 180's. using
n320/340 the handguns of use will be a Sig P229 and a Sig p226 Elite

 

[Southernsorrow]

I get pretty good accuracy using hornady 180gr TMJ's under 5.6 of n340 if I can get close to the same using plated rounds I'd be a happy handgunner.

 

[Walkalong]

The Vihtavuori online PDF has some data using plated bullets. Check there.

Link to some plated data

 

[Southernsorrow]

pretty much same thing I've been finding. everything on 155's and very little on 180's nothing on 165's

 

[Southernsorrow]

can't load them as lead an can't load them as jacketed. I don't really want to guesstimate a start/stop for the plated. searching online might turn up a hit or 2 on 180's but those are mostly using other brand powders. I can't find anything on 165's.

 

[Walkalong]

Load them to 75% to 80% of jacketed data. Work up carefully from there. If you are not comfortable doing so, do not. Good luck finding specific data.

 

[Berry's MFG]

Wish I could help you with data for Vihtavouri, since leaving PHX I have lost my cheap source for that powder. You can start at a mid-range jacketed data and check results. We are making a prototype bullet for a client right now that has thicker plating, is a hollow base FP in a 165gr. It is the same OAL as the 180 FP. I have some on my desk right now that I need to fire in the tube, if they accept the bullet I am sure it will make its way into our line. It will be a bit more due to the extra copper.

 

[Southernsorrow]

have not gotten around to trying them yet due to work time of day and or weather once I get home. but I'm pretty comfortable working with 3.7-4.7 and I'm going to try it out tomorrow from 3.8 to 4.6 in .2 grain intervals using n320. I'm not going to worry about the n340 for now, since I probably only have enough to do about 20 rounds. I'll just use that up on my handful of 165gr Gold dots.

 

[Riss]

If I recall the N320 is faster than the N340. Speed is what can kill an unsupported 40 S&W case so I would go with the slower powder. N340 is also a slightly larger charge and less likely to be able to double or triple charge a case. I use between 4.5 gr and 4.7 gr of N340 to make major with a 180 gr lead hard cast TC depending on what gun I am using.

 

[Walkalong]

For full loads N340 is definitely the better choice, but proper amounts of N320 will be fine. Both excellent powders.

 

[Gadzooks Mike]

I get pretty good accuracy using hornady 180gr TMJ's under 5.6 of n340

Here in Alabama, we put the bullet on top of the powder.

 

[raz-0]

From my experience, follow lead data for rainier, and jacketed date for the berry's double struck. Watch your belling and crimp, and both seem to be happiest with a power factor around 150 out of a 4" barrel if you are looking for accuracy.

I dunno where you are finding them 40% cheaper than TMJ stuff. Hornady HAP is no longer enclosed base (but when it was, I could see the 40%), and that leave montana gold CMJ. the montan gold CMJs are nice.