300 Norma Improved. Load testing, info, and builds

[rpierce]

I recently had a similar experience with my 338AM. Haven't shot it in a year or 2 and I keep some powder in an old fridge in the garage that I vented. That's where I happened to have my H50BMG, all same lot#. I live in a dry desert climate with huge temp swings through out the seasons. When I went to shoot my standard 142gr load velocity was 100 fps less than usual. I ended up bringing the charge up 3grs to 145gr now to get things back the way they were. Powder has a certain amount of moisture content and mine had no doubt dryed out somewhat. I'm bringing everything inside now where the temperature is more stable year round.

Excellent shooting and thanks for sharing. The Norma Mag IMP case is something special!

Wow. That's a lot of powder to bring it back up from drying out. Ive been thinking about just opening up all my cans and letting them air out for a week. Then they should be good to go and I won't have to worry about it changing.
The norma improved is a awesome case. Especially now that lapua is making the brass. I have a piece with 28 warm firings on it and the primer pocket is still tight.

 

[DJ Fergus]

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Wow. That's a lot of powder to bring it back up from drying out. Ive been thinking about just opening up all my cans and letting them air out for a week. Then they should be good to go and I won't have to worry about it changing.
The norma improved is a awesome case. Especially now that lapua is making the brass. I have a piece with 28 warm firings on it and the primer pocket is still tight.

have 7lbs of n570, manufacture date 2015. 6 sealed cans. Im liking your idea of letting it air. out Seems like it should slow burn rate a little, which would probably work out nice.

 

[Rhovee]

Letting the powder dry out is a terrible idea. It has Nitrocylicerin. That's what makes it so fast. If you dry it out, it's going to make the powder burn faster not slower.

 

[bigbulls]

Out of curiosity, if a mild node with 215 bergers puts you at 3145ish fps where will the 230 bergers velocity be?

 

[rpierce]

Letting the powder dry out is a terrible idea. It has Nitrocylicerin. That's what makes it so fast. If you dry it out, it's going to make the powder burn faster not slower.

What do you suggest to do then? If you don't load a whole pound worth at the same time then its going to be slightly different then when it was first opened. I was talking about it to a few other shooters and one guy throws all his VV N150 onto a clear tarp that's suspended in the air for a few days and then pours it back into the containers.

My experience was it only dried out very minutely. About .2 worth of powder. Not enough for me to worry about it changing the burn rate significantly. However I was at the bottom of the node when I did my seating depth test and i feel it was enough to take me out of the sub inch vertical node. Ill just add .2 gr worth of powder into my next test and see if it goes back into its sub inch vertical node at 1000. My thoughts were if Im in the bottom of a node in really cold weather Ill still be in the node when its hot out. Granted the node was really wide but still.

 

[rpierce]

Out of curiosity, if a mild node with 215 bergers puts you at 3145ish fps where will the 230 bergers velocity be?

Most of the guys are between 2930 and 3035 fps. You can go faster but the nodes are much narrower.

 

[Rhovee]

I was referring to opening the pound and letting it dry out. I talked to VV about it a few years ago. They mentioned it takes years to dry out. But when it does, it gets hotter.

 

[bigbulls]

Have any of you 300 NM improved guy's run any 230 A-Tips yet? How are they shooting? Powder grains the same as 230 bergers? seating depths? groups?

 

[DJ Fergus]

I know that this is not what you asked for so may not be helpful. I have shot a very limited amount of 230 a-tips in my nonimproved 300 nm. I ran 3000 fps with 225elds and 230 a-tips with the same charge of n570. 230 otm was faster than those two with the same charge of n570. Otm was around 3030fps. 26 inch brux 9.50 twist.

 

[rpierce]

Rhovee: That's odd that it takes that long. I wonder why I had a difference so quickly.

 

[bigbulls]

I know that this is not what you asked for so may not be helpful. I have shot a very limited amount of 230 a-tips in my nonimproved 300 nm. I ran 3000 fps with 225elds and 230 a-tips with the same charge of n570. 230 otm was faster than those two with the same charge of n570. Otm was around 3030fps. 26 inch brux 9.50 twist.

Thanks djfergus that the kind of info I'm looking for, did your seating depths stay the same? I read in another place that they had to seat the A-Tip a lot deeper to get it to shoot which increased velocity and they had to back off powder grains, .100" jump

 

[Rhovee]

I have had rifles do that. They shoot 3100 all day long. One day it shoots 3075-3080 but groups and poi is the same. I would try that group again and another with .3 more. But a 3" triangle at 1k is nice. One day it might be 2.5. Next day 4".

 

[rpierce]

I have had rifles do that. They shoot 3100 all day long. One day it shoots 3075-3080 but groups and poi is the same. I would try that group again and another with .3 more. But a 3" triangle at 1k is nice. One day it might be 2.5. Next day 4".

Ya. Im definitely not complaining about the 3" group. Next time I go out Ill hook both Labradars up and see what they say.

 

[DJ Fergus]

Thanks djfergus that the kind of info I'm looking for, did your seating depths stay the same? I read in another place that they had to seat the A-Tip a lot deeper to get it to shoot which increased velocity and they had to back off powder grains, .100" jump

Over the past three days ive shot 230 a-tips, 230 otm, 225 eld ,215 Bergers, and 208 eld's. I had to change seater die for all of them to be .020 from the lands. Im sorry but I can't remember, I think I had to run the seater die out and seat longer for the atips & I had to seat deeper for otms. I have a 9.5 twist. For some reason it loves the 208 eld's. Almost fool proof. No matter what, it will do no wrong with them. I wish it loved the 225 eld's. I haven't tested enough with the atips but in order of what bullets it likes : 208 eld, 215 Berger, 230 otm, 225 eld. I think someone who shoots competitively could stand chances of taking home several medals with this rig & 208 eld's. If I had it to do over again, I would go 9 twist & possibly 8.5 twist.