Can anyone confirm this max load data....

P

Pond James Pond

New member
.... through a source other than VihtaVuori?

And how full is a full-case load?

I'm prepping a test ladder for my AR. I've already prepped a set of charge weights with N135 and tonight a dropped a set with N140.

My bullet of choice here is a 62gr PRVI FMJBT and I'm hoping it will gel with my rifles 1:7 twist more than the 55gr factory loads I've been shooting.

Loading the N135 was uneventful, but the with N140 VihtaVuori data stated a full-case max load at 26.2gr (for a Speer 62gr FMJBT), so I used this as a my max load to calculate the lower charges from.

However!..... even my charges at about 25.4gr were into the neck of the case and I can'r see how I'll be able to seat a bullet like that boat-tail and not compress the powder.
I poured one dose of 26.2gr and it filled the case to the brim!! So far I have stopped prepping cases beyond the 25.9gr load and even that I think may need to be pulled for the same reason.

So I'd like two things from folks if they can help.

Firstly, does a full-case load mean to the brim and so inevitably a compressed load of powder (I had assumed not, but rather that once the bullet was seated you'd just have not rattle-room).

Secondly, can anyone confirm that a 62gr FMJBT in .223 Rem will hit the max charge around 26gr? However, this must be from a source other than VihtaVuori.

Thanks in advance!
 
Why not use the chart from the maker of the powder?? you can start with 10 round and add .50 grain in the next 10 and work your self up a good 1/2 in at a 100 yd jest start 1 grain BELOW MAX to start.
 
most of my heavyweight 223 loads are compressed if using and type of stick powder, 4064, varget, sc or whatever. I actually like it compressed, the crunch feels nice.

I know nothing if your powder, usually it will state next to the load XX.X(C)gr. obviously "C" meaning compressed load
 
Something fishy in Finnland?

The Viht. 2015 load guide is available here http://img.materialbank.net/NiboWEB...9&cartUuid=6162349&uuid=8154270&type=original
and lists that load as:

"N140 1,62 25.0 901 2956 1,70F 26.2F 943 3094
. . .
F = Case full"
Therefore, it is a compressed load (which is not a bad thing).
My Sierra bullets data (223 AR) does not list a 62 gr bullet, but their 63 & 65 (same set of data) grain loads do not use this powder (N140), nor do any of their data until bullet weight of 69 gr is used, which uses 25.1 grains. Sierra does not indicate whether loads are compressed. Sierra 223 Bolt guns data do not use this powder.

I have heard of Viht data equaling, or even exceeding, case capacity. For example they list a 9mm 147 gr load at ~1200 fps which is rumored to be hyperbolic.
 
Weird....

Previously, because my handloads are always a mish-mash of components I can get hold of, afford or both, I have tried to get multiple max loads from different sources where the components approximate to the highest degree possible. I then find the mean amongst them.

This time around I found the exact bullet weight and type (if not the bullet itself) on the page of my powder's manufacturer. For that reason, I felt pretty confident just using that.

If compressed loads are not the end of the world (or gun) then I may give it a go. As it happens my 3 bore-fouler rounds are below the min load, starting at 24.1gr.

Even at that charge, I think the fully seated bullet will be dipping its tail in the powder!

I have just charged the last 5 with 26.2gr nd the level was about 3mm from the mouth!! It was that full! I was able to seat the bullet =at its preliminary depth which I do so as not to have open cases full of powder lying around. I'll know more when I've seated them full to my chosen OAL of 57.4mm which is dictated my the mag size, although I will be getting my Hornady chamber gauge .223 case adaptor next week so I will check that this OAL doesn't touch the lands although I'd be mighty surprised if it did!!

Why not use the chart from the maker of the powder??
Click to expand...

Well, that is what I'm doing except the manufacturer didn't use my cases, primers or bullets! Only the bullet weight and powder are in common with the manufacturer's data. So whilst its a safer bet, it's not fool-proof.

My first charges are indeed about 1gr below min. I then have 5 shot batches at 0.2gr increments. That seems very small to me, but those are the charge weights the Optimum Charge Weight method put out in calculations.

Perhaps the Newberry OCW method is not ideal for such small case capacities as .223.... the differences are so slight but, then again, if a node does exist I should see several tighter groups all together which will help me in finding it.
 
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All seated: First few were very smooth. At 25.4, a bit of resistance. A bit more at 25.7 and more still at 25.9.

At 26.2gr there was a faintly audible crunch from the case. :eek:

I think I'll be brushing up on my semi-auto overpressure signs and indicators before I go to shoot those!
 
A little compression, every now and then, is not a bad thing...

...apologies to Thomas Jefferson, but I couldn't resist the paraphraxis.

I don't think that compressed powder charges, in and of themselves, are bad things. Some of the more accurate rifle loads I've shot are SLIGHTLY compressed. I think it's when the powder charge is HEAVILY compressed that the handloader tempts fate. Where is the dividing line ? I'm not sure, but I'll bet that if said powder charge cannot be introduced to the case, even with a drop tube, you're probably there.

Numbering your cases, then measuring case head expansion of fired vs. unfired cases may be your best guide, unless you have access to a strain gauge. If the case heads expand more than 0.0005", I think I'd back off "forthrightly and without embarrassment" as a character of fiction once said. I ALSO think that case head expansion of 0.0004" would NOT be an indication for me to proceed, though 0.0005" would serve as an absolute max.

You should also probably number, measure, and shoot some factory-loaded ammo through it, to be sure that you're not already getting 0.0005" expansion from "safe" ammo. If so, then the case-head expansion method probably won't work for that rifle.
 
Also, we are talking about "stick" powders, right? Those settle very differently than ball powders. A longer drop tube helps the prescribed powder settle lower. You could also vibrate the charged case.
 
Ditto the above. Look below to see what using drop tubes does to how 4064 settles. Any stick powder will have a degree of this response, spherical powders much less so.

droptube_zpsd1504b97.jpg
 
Well, that photo is reassuring. I did rattle the powder about a bit and it settled about another 2-3 mm.

I'll be monitoring the lower charges carefully and if I shoot the max load I may do so with a word to the powers that be as I pull the trigger... But at least it looks less like I have loaded myself a doomsday device for my AR!!
 
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