Load Development in 10degF and temp sensitivity

[A5scott]

I am getting ready to do load development for 6.5x47, I live in eastern PA and its in the teens, and I'm going to Florida for March to shoot, and it should be in the 80's.

I am using Varget, VV N540, CCI 450's, RDF 140's and Warner Tool 121gr. 24" MPA build.
Lab Radar.
I will use the Scott Satterlee method of loading 10 rounds .2gr increments and trying to get velocity nodes.

I know Varget is fairly temp insensitive, but I can't find a definitive answer on the VV N540 and how it reacts to temperature.

Has anyone tried a Lab Radar indoors at a 20 yard or so range? Or should I try keeping my ammo relatively warm and shooting outside? I'll have to shoot outside anyway when I try to find seating depth.

I'm gonna send emails to VV and Lab Radar to see what they have to say, but I figure I'd ask here as well, to get an idea of other's experiences.

Thanks,
Scott

 

[Badfinger]

All I can say is that in my .308 I love Varget, I just shot a 3 round one hole group off my deck at 8* the same POI and grouping as at 80*!!!

 

[MakeSawdust]

If you are checking for pressure I would try to keep the gun and ammo around 80* if possible. If you are not going to push the limits of velocity and pressure you will probably be okay with a properly developed load at both temp extremes. I believe ( someone please correct me if I'm wrong) that N540 is double based which would mean it is likely temp sensitive. I would probably try to develop a nice mild, accurate load and then maybe look for a higher node when things warm up. It would be a bad situation to travel and have a load that's sticking the bolt or blowing primers. Good luck.

 

[kansas]

I use H4350 in my .260 and three years ago now I was doing load Development. H4350 is supposed to be the LEAST temperature sensitive of any powder however as the temperatures rose my load was causing pressure signs so I had to back down half a grain. I live in Kansas so temps were in the 10-30 degree range during load Development.

 

[spife7980]

Put each group in a different zip loc and keep them inside your coat pocket. Don’t leave them in the barrel too long before shooting. Run many sighters to get the barrel up to non frozen and then shoot them fast enough to keep it up to temp. It will cool quickly.

 

[A5scott]

Thank you all,
Yes I'm just trying to find a load around 2675-2725 fps with the 140's and maybe 2850 to 2900fps for the 121's. I don't want to try to max out the velocity.

I also have a magneto speed, so I may use that plus the LabRadar. I called Labradar and they said that 15 yards is the minimum distance needed, and it is doable indoors. That and my indoor range are only 10 minutes away anyway, so maybe I'll try to find the velocity indoors.

I have one pound of 4350, but it's basically unobtanium for me, so I'm happy to use Varget.

thanks again,
Scott

 

[padom]

37g Varget with a 140g bullet .005" off lands is a nice low node tack driver. Lapua brass CCI 450. 140 ELD-M and 140 Hybrid in my 26" Bartlein 6.5x47L right at 2800 single digit SD.

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[A5scott]

Nice shooting! Yes, I'm hoping to find a good node between 36.5 and 37gr Varget.

Thanks,
Scott