Adjusting load for elevation

[Albert]

I've been shooting f-class in the upper Midwest, using a straight 284. The load, utilizing H4831sc and 180 Berger hybrids gives me 2830 fps and zero pressure problem. Will this load behave differently in Raton? Will I need to adjust it?

 

[Ringostar]

At that velocity you should be ok. However your elevation settings will be different. For 1000yds, I have a 3 moa difference from Lodi Wi to Raton/Capitan.

 

[Tom Jones]

Same here about 3 to 4 minutes difference from my local ranges at about 500 feet to Raton. I have blown primers at Raton so there will be a pressure increase. Tom.

 

[fivering1]

Same here about 3 to 4 minutes difference from my local ranges at about 500 feet to Raton. I have blown primers at Raton so there will be a pressure increase. Tom.

You better check your physics. The slight barometric change in atmospheric pressure will not nearly be enough to blow primers that are OK at lower altitudes. The higher temperatures you may have experienced certainly may. Actually sounds like loading error.

 

[Rope2horns]

Two minutes was the difference between my gun at home versus Raton...right around 500' elevation here.

 

[mikecr]

Will this load behave differently in Raton?

NO

Will I need to adjust it?

NO

 

[Dusty Stevens]

Your load isnt the same as yesterday even at the same bench. It may be acceptable to what youre doing but it does change

 

[Albert]

Thanks for the feedback. This load has been fine in 90 degree temps but the humidity was probably higher than New Mexico will be. I'm expecting the extra 6000 feet of elevation to be the main difference and shooting flatter is logical. I just wanted some assurance from those who have done it that I wouldn't see a significant pressure increase. Thanks again

 

[Bindi2]

Thanks for the feedback. This load has been fine in 90 degree temps but the humidity was probably higher than New Mexico will be. I'm expecting the extra 6000 feet of elevation to be the main difference and shooting flatter is logical. I just wanted some assurance from those who have done it that I wouldn't see a significant pressure increase. Thanks again

You will see a significant change if your load is on the upper end. Theory says it wont practice says otherwise.

 

[Scott Harris]

I've been shooting f-class in the upper Midwest, using a straight 284. The load, utilizing H4831sc and 180 Berger hybrids gives me 2830 fps and zero pressure problem. Will this load behave differently in Raton? Will I need to adjust it?

The elevation difference won't change your load much. Temperature differences are more important. It will be cooler in Sept in Raton, so you definitely won't have any pressure problems. H4831 doesnt change much across fairly wide temps. We upped our load going from Phoenix to Raton last year by a few tenths...proved unneeded.

regards,
Scott

 

[XTR]

One of the things that happens at Raton that probably doesn't happen at your local range is that your kit sits in the sun all day, from the time you get it out of the truck at 0700 until you pack up at the end of the day. There is no shade. Ambient temp isn't necessarily the problem, radiant heating from the direct sun can get your ammo temp up a fair bit more than you may want.

If your load isn't pushing the edge then you'll be fine. If it's working at home in summer heat then as long as you don't leave it sitting in the direct sun, or in your truck at 120F for hours while you are in the pits you'll be fine.

 

[dmoran]

Your load isnt the same as yesterday even at the same bench. It may be acceptable to what youre doing but it does change

Depends on how big the node is, the cartridge, and how sensitive the powder.

In a 6PPC running at high pressures (like your so often referring to), there often is little room.
But say with a 300-WSM, the node may be several 10th's wide, and not need adjustment as soon and/or not as fussy.

All of which is why what one see's and/or experiences in one cartridge very well may differ in another cartridge.
And why what is generally gospel in one discipline, often may not be in other's.

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