Why N320 Powder?

[efether]

I've been spending many sleepless hours reading this forum (WOW! It's great!!), and I keep seeing post of people recommending Viavardi N320 powder for .40S&W. I go to their web site, and refer to my two reloading manuals (SPEER and LYMAN's), and there's nothing on that powder for .40S&W. They list N340, N360 and 3N37...but no N320. Now, according to their burn-rate chart, N320 burns fastest...and I've read here that with heavy bullets, burn fast powders. But why? And why the N320 when even Viavardi doesn't show it used in that caliber? Also, what's a good load (180 grain FMJ) to start with? What performance should I expect with a 5" barrel and a 1.122" OAL?

I'm seeking enlightenment. Any replies are appreciated

Thanks,

Eric Fether

efether@pukin-dogs.com

[Carlos]

You asked: "Also, what's a good load (180 grain FMJ) to start with? What performance should I expect with a 5" barrel and a 1.122" OAL?"

DO NOT attempt to load to 1.122" OAL. - I am aware that that number is listed as the MINIMUM oal or col in the Speer & Vihta Vuori data. However, the MINIMUM OAL actualy means: "minimum safe OAL" Go shorter than that and pressures can sky-rocket & cases will blow. It is beyond me why reloading manuals FAIL to make that clear.

In a Glock or other .40 based on the OAL of the 9mm, you can usually load out as long as 1.155" without danger of getting near the lands & the cartridge fits fine in the magazine (usually feeds better too).

I will leave it up to others to explain why we so often use N320 even though it is not listed (in a nutshell - we are mostly loading out to 1.200" to 1.220" & shooting it in 1911 .40s with long-throated barrels. It is NOT appropriate nor safe for loading short; like to absolute MINUMUM .40 OALs & still trying to exceed major)

Regards,

D.C. Johnson

[XRe]

As to why... search on "ejecta" - I think that will turn up the threads where the physics of recoil impulse are discussed. The short answer is - the less stuff you have coming out the front, the softer the gun appears to shoot and the more controllable it appears to be. You use less powder with a faster burning powder, so you have less stuff coming out the front, and therefore less recoil.

I think you'll find some folks running Titegroup or N320 at shorter lengths on the forum - I've just done a bunch of this research, myself. But - the rule of thumb is that the shorter OAL .40s are safer with slower powder.

I'm loading to 1.180" OAL (longest that works perfectly in my gun - a 1911 single stack), with a 180gr bullet of some form. I'll be chronoing shortly, so I can't give you details, yet.

What gun are you loading for?? Knowing that would help us suggest a starting point for loading .40.

[achard]

Also depends on the weather temperature. for 180grs and oal 1.2" starts @ 4.7 grains also 4.9 grains and chrono to make it sure.

[davidwiz]

SAAMI over all length for a .40 S&W is 1.135 - I wouldn't load less than that, or you are going to get massive pressure problems.

[GuildSF4]

As Xre says softer recoil impulse/ feel, softer gas jet out the front.

My V V N320 load is 5.1 grains, 180 grain JHP or FP Billy bullet loaded at 1.20 OAL.

Also as Xre, davidwiz and Carlos suggest load long, preferably as long an OAL as you can for your gun and mags... longer OAL = lower pressure.

[XRe]

Also as Xre, davidwiz and Carlos suggest load long, preferably as long an OAL as you can for your gun and mags... longer OAL = lower pressure.

<{POST_SNAPBACK}>

Besides flattening the pressure curve out some, loading to a longer OAL also gives you a load with a little more tolerance for things like slight bullet setback, temperature increases, change in lot to lot component variations, variations in case capacity, etc...

Tolerance is a good thing with a high pressure cartridge

[efether]

What gun are you loading for?? Knowing that would help us suggest a starting point for loading .40.

<{POST_SNAPBACK}>

I'm shooting a Glock 35 with a Custom Fitted Bar-Sto Match grade Barrrel. What would be a good OAL? I setup the 550 to 1.122, which is longer than Lyman's recommends (1.150) and shorter than SPEER (1.125).

Question -- A longer OAL has less pressure pressure than a shorter OAL. Makes sense. However, how does this effect FPS? When trying to achieve a Major load with a 180 grain FMJ, I figure 940 fps is a good target to shoot for.

Also, by the sound of it...you want to use as little powder as possible to reduce "the amount of stuff coming out of the barrel." But I've read that a compressed load is more accurate...I've also talked to people who use Grits (yes, as in corn meal) to "top off the brass" to create a compressed load. I was also told that the grits help keep the barrel clean. Comments on this idea?

Thanks for the help.

-Eric

[GuildSF4]

I'm shooting a Glock 35 with a Custom Fitted Bar-Sto Match grade Barrrel.  What would be a good OAL?  I setup the 550 to 1.122, which is longer than Lyman's  recommends (1.150) and shorter than SPEER (1.125).

Question -- A longer OAL has less pressure pressure than a shorter OAL.  Makes sense.  However,  how does this effect FPS?  When trying to achieve a Major load with a 180 grain FMJ, I figure 940 fps is a good target to shoot for.

Also, by the sound of it...you want to use as little powder as possible to reduce "the amount of stuff coming out of the barrel."  But I've read that a compressed load is more accurate...I've also talked to people who use Grits (yes, as in corn meal) to "top off the brass" to create a compressed load.  I was also told that the grits help keep the barrel  clean.  Comments on this idea?

Thanks for the help.

-Eric

<{POST_SNAPBACK}>

Simple answer for OAL is to use the longest lenght you can reliably fit in your magazines. I am sure some of the Glock shooters here can let you know what OAL they use.

You do not want to use any fillers with a high pressure cartridge, this can cause major problems.

[davidwiz]

Simple answer for OAL is to use the longest lenght you can reliably fit in your magazines. I am sure some of the Glock shooters here can let you know what OAL they use.

In my Glock 23, I can't fit my 1.150 oal IPSC .40 ammo in the mag as it too long.

[XRe]

I'm shooting a Glock 35 with a Custom Fitted Bar-Sto Match grade Barrrel.  What would be a good OAL?  I setup the 550 to 1.122, which is longer than Lyman's  recommends (1.150) and shorter than SPEER (1.125).

The factory stuff I have in front of me (UMC) is 1.130. I haven't heard of it not running in a Glock. However - load up some dummies (no powder, no primer) with the bullet out longer than you would probably load (say, 1.150). Check them in the mag - then start bumping the bullet back slightly on them until they'll fit in the mag to full capacity and feed by hand in the gun. That will show you empirically how long you can load the bullet you're using, in your gun.

Question -- A longer OAL has less pressure pressure than a shorter OAL.  Makes sense.  However,  how does this effect FPS?  When trying to achieve a Major load with a 180 grain FMJ, I figure 940 fps is a good target to shoot for.

Lower average pressure is going to mean a slower bullet - so you have to use slightly more powder to make major (a couple of tenths, or so, generally). The real difference is in how the pressure builds - the shorter the OAL, the greater the tendency for it to spike up quickly, and sometimes much higher than the gun and case can handle (the faster the powder, generally the quicker and more sharply it spikes up, too....).

The VV hardcover manual used to have a great discussion on how the different loading variables (inc. OAL) affect pressure in the cartridge.

Also, by the sound of it...you want to use as little powder as possible to reduce "the amount of stuff coming out of the barrel."  But I've read that a compressed load is more accurate...

The idea here is consistency of ignition. The powder lays in the case exactly the same every time in a compressed load. But, any load that fills most of the area between the base of the bullet and the case web is going to approach that consistency level, anyhow. There are various factors that affect it, too - consistency of cases, characteristics of the powder, etc. You have to be careful with compressed loads in some cases - the single base VV stuff is reasonable with it, as the pressure builds linearly, but double base powders have been to known to make some... "interesting" pressure changes once they go compressed (and even before that, too... that nitro is unstable stuff....).

So, you don't have to have a compressed load to have an accurate load. BTW - a major N320 load pretty much seems to fill up that air gap.

I've also talked to people who use Grits (yes, as in corn meal) to "top off the brass" to create a compressed load.  I was also told that the grits help keep the barrel  clean.  Comments on this idea?

<{POST_SNAPBACK}>

I wouldn't even begin to bother. You're shooting a Glock, man, come on You're not going to get MOA accuracy out of it

The only reason I can figure grits might keep the barrel clean is because the remains of them would become an abrasive inside the bore... and will wear your barrel out in short order while it's staying nice and shiny.

Do a search around the forum for short N320 loads in .40 - I think there are some lurking here. With short loaded stuff, you might be better off with N330 - I think you'll find some loads for that, as well.

[efether]

I reset the OAL up to 1.137". I loads fine in the mag and the chamber. Sound like a good number to stay at?

Thanks!

-Eric

[D.Hayden]

Sounds long for a Glock, but if it feeds, you're good to go.

You might do a number of mags worth of rounds, with mag changes, make sure they all feed. 100% is what you're going for not 99%.

For my Production guns, I load at 1.125 (but they're minor), S_I are 1.165 (major)

[Carlos]

See my original post. 1.155" for Glock (and no shorter). Even at that length, N320 is marginal safety wise (one reason NO one will publish a book listing it for .40 - it is not safe in the hands of inexperienced reloaders going for major) & you would be wise to use N 340 or titegroup if there is a chance of set back. What dies are you using? Specifically, sizing and crimp die brand? Keep the questions comming - this is a good discussion. Regards, C.

[GRW]

1.135 is the longest that I have been able to load in .40 that will function in my hi-cap mags. You can load a little longer in the 10 rounders because the rounds are not stacking like those in a hi-cap.

[efether]

See my original post. 1.155" for Glock (and no shorter).  Even at that length, N320 is marginal safety wise (one reason NO one will publish a book listing it for .40 - it is not safe in the hands of inexperienced reloaders going for major) & you would be wise to use N 340 or titegroup if there is a chance of set back. What dies are you using? Specifically, sizing and crimp die brand? Keep the questions comming - this is a good discussion. Regards, C.

<{POST_SNAPBACK}>

I'm using Dillion's Carbide Dies. I opened the OAL to 1.130 and it "appears" to feed fine and no hangs in the mags.

I would concede your 1.155" for a stock Glock Barrel, but I'm using a custom fitted Bar-Sto Match Grade Barrel. Wouldn't that make a difference? That stock Glock barrel had WAY too much head space...this Bar-sto is tight. I can take a spent case and it'll fit into my Case Guage...the brass from the stock Glock couldn't.

Thanks!

-Eric

[GuildSF4]

I would concede your 1.155" for a stock Glock Barrel, but I'm using a custom fitted Bar-Sto Match Grade Barrel.  Wouldn't that make a difference?  That stock Glock barrel had WAY too much head space...this Bar-sto is tight.  I can take a spent case and it'll fit into my Case Guage...the brass from the stock Glock couldn't.

Thanks!

-Eric

<{POST_SNAPBACK}>

Bar-Sto barrel could make a difference in how long you can load. The barrel leade may be different (Leade is the distance between the end of the chamber (where the case mouth would sit) and where the rifling starts). For the barrel the longer the leade is the longer you can make the OAL (although you do not want the bullet touching the rifling as this can drasticlly increase pressures).

Headspace is the distance from the back of the barrel hood to the end of the chamber.

The Bar-Sto barrel has a tighter chamber (smaller diameter), probably very close on the head space, the leade could be longer or shorter (more likely shorter). Hope this helps FWIW.

[recon215]

As Xre says softer recoil impulse/ feel, softer gas jet out the front.

My V V N320 load is 5.1 grains, 180 grain JHP or FP Billy bullet loaded at 1.20 OAL.

Also as Xre, davidwiz and Carlos suggest load long, preferably as long an OAL as you can for your gun and mags... longer OAL = lower pressure.

<{POST_SNAPBACK}>

Guild,

Just got my bench setup and loaded some dummy rounds to 1.20 OAL. If I have been reading in here correctly, when I load up a mag and hand cycle the rounds thru the gun and they all cycle as they should, this OAL should be right for my gun? I am shooting a Para P16 w/factory barrel. Also, your load of 5.1 grains of V V N320 makes major? What power factor, if you know offhand?

Thanks for all the help in here guys/gals!!!

[GuildSF4]

Guild,

      Just got my bench setup and loaded some dummy rounds to 1.20 OAL. If I have been reading in here correctly, when I load up a mag and hand cycle the rounds thru the gun and they all cycle as they should, this OAL should be right for my gun? I am shooting a Para P16 w/factory barrel. Also, your load of 5.1 grains of V V N320 makes major? What power factor, if you know offhand?

Thanks for all the help in here guys/gals!!!

<{POST_SNAPBACK}>

My PF is about 175-180, definitely major in my gun, you should make major however you will want to chrono it. The OAL should be fine in a Para; you will need to run a large sample through to make sure they have no problems. (General problem areas are feed ramp and dirty mags, if it hand cycles feed ramp should be OK, no guaranty though.)

[efether]

Bar-Sto barrel could make a difference in how long you can load. The barrel leade may be different (Leade is the distance between the end of the chamber (where the case mouth would sit) and where the rifling starts). For the barrel the longer the leade is the longer you can make the OAL (although you do not want the bullet touching the rifling as this can drasticlly increase pressures).

Headspace is the distance from the back of the barrel hood to the end of the chamber.

The Bar-Sto barrel has a tighter chamber (smaller diameter), probably very close on the head space, the leade could be longer or shorter (more likely shorter). Hope this helps FWIW.

<{POST_SNAPBACK}>

Thanks...I always referred to the chamber as the chamber in the past...but read somewhere that it was called headspace, and changed my reference...so I truly appreciate your clarification.

Now...question -- how can I tell if the loads I make are touching the rifling? I'm loading FMJ...and the lands/groves don't mark it as they would lead bullets. So, any insight on this would be helpful.

From what I'm hearing...sounds like 1.130" - 1.135" SHOULD be acceptable in my glock with 3N37, N340 or N350 powder. But N320 might be pushing it. Am I understanding this right? That with the faster N320 powder, OAL becomes MORE critcal, and should be the longest OAL the barrel/magazine can handle. However, Carlos stated,

See my original post. 1.155" for Glock (and no shorter).

Yet, when I posted that I extended my OAL to 1.138" I was told BerKim,

Sounds long for a Glock, but if it feeds, you're good to go.

And GRW said,

1.135 is the longest that I have been able to load in .40 that will function in my hi-cap mags.

.

So...it's pretty confusing. What is the BEST recommendation out there? How much difference can 0.05" ot 0.015" really effect the pressures. I mean...geez, that's not much space at all...15 Ten-Thousandths of an inch...

Also, how much of a difference is there from N320 to 3N37 to N340 to N350? And what if I use Winchester 231 or Universal Clays. I can hit Major with any of these powders...and the Winchester and Clays is cheaper than Viavardi...and easier to get.

Man...I got into reloading to save $$$ in my shooting...but it's getting more and more expensive...different powders, a Chrony, bullets of the tested loads, range time...etc. Geez....

Thanks again for everyone's help...now if I can just consolidate it down to one firm answer.

-Eric

[JFD]

I use Titegroup because of all the praise for it here. No complaints from my end at all.

My Para P16 feeds and functions just fine with 1.20 OAL (to answer the Para question above).

I actually run 4.7 grains of Titegroup at 1.197 for my Para with factory barrel. 4.6 will make major, but it's a little bit close.

Of course ignore this data if you have a Glock.

[GuildSF4]

Now...question -- how can I tell if the loads I make are touching the rifling?  I'm loading FMJ...and the lands/groves don't mark it as they would lead bullets.  So, any insight on this would be helpful.

<{POST_SNAPBACK}>

You can load a few different long OAL dummy rounds with no or very light crimp mark the bullets with a black marker, then use your barrel out of the gun as a gauge. Guage them as if using a regular gauge, if they are way too long the case will not sit even with the barrel hood, and you should see the rifling marks in the marker. Shorten the OAL until the case sits properly, and you no longer see the rifling marks in the marker. Back off OAL a couple more thousands to make sure the bullet is no touching the rifling. (OAL of 1.135 sounds about right to me, and you can PM Flex, he shoots a Glock.)

How much difference can 0.05" ot 0.015" really effect the pressures. I mean...geez, that's not much space at all...15 Ten-Thousandths of an inch...

<{POST_SNAPBACK}>

It can make a huge difference when the OAL is really short, or if you are too close to the rifling.

Also, how much of a difference is there from N320 to 3N37 to N340 to N350? And what if I use Winchester 231 or Universal Clays. I can hit Major with any of these powders...and the Winchester and Clays is cheaper than Viavardi...and easier to get.

<{POST_SNAPBACK}>

Universal Clays is a good powder, very clean, inexpensive, and makes major easily. (Note: Make sure it is Universal Clays, and not Clays, Clays can blow up your gun.)

Also a lot of people use Titegroup. 231 very dirty. As for the other V V powders price makes them non selections for most people.

Hope this helps.

[davidwiz]

With the Glock, my first priortity would be that the rounds fit into and feed out of the magazine. The factory Glock bbls will take rounds that are loaded 'long' but you might have trouble with them feeding in the magazine.

[Carlos]

Calrification of OAL:

My 1st post suggested an OAL appropriate for Glock. It was not revealed in the 1st post that you are using a Bar Sto. I missed it the second time. It changes things as it may be possible to touch the rifling- I have no idea what sort of leade they cut on a Bar Sto (FYI - I have fired 1.200" .40 in a STOCK glock barrel. You have to single load it, but there is enough leade.).

I appears that others are having trouble loading whatever bullets they use to longer than 1.135". With hollow points, that may be so.

If you are limited to 1.135", then I would not attempt N320 Major .40.

However, there are many published loads for Titegroup (TG) at Major & can be loaded to 1.135". Also, Titegroup in 8 lb jugs is about $90 to 100 bringing the price a little over $12/lb. - very inexpensive & safe.

As doe N320 vs other V V powders, check a burn rate chart.

231 is temp sensitive and very dirty compared to TG in Major .40.

I got Universal to work, but its finicky (search on Universal for more info) and it kicked hard.

For your use & to save $$$$ , I suggest Titegroup. Regards,

D.C. Johnson

PS - I would throw out the Dillon sizing die & use a Lee or better yet, a Lee U die from EGW.

[Flexmoney]

Not much to add here....

One thing, OAL should first be adjusted so that the gun runs 100%.

Within that function range, loading longer should decrease pressure (a smart goal). So, the idea (often) is to load as long as you can get away with...without loading so long as to engage the rifling (which increases pressure).

I load 1.135 OAL in the Glock 40's, with TG and Zero 180g JHP's. That load works in the Glock brand and KKM brand barrels that I have tried...and, in Glock mags.

I won't load 40 without a Lee Factory Crimp Die (FCD).

I won't load 40 major with 231. I just don't trust it.

I have a pound of vv320 sitting on my shelf...for over a year. I can't bring myself to be curious enough to try it. TiteGroup works well enough that I haven't wanted to look elsewhere.